Welding helmets are a crucial aspect of personal protective equipment for any welding operator. They protect from the intense glare and eyesight-damaging light from a welding arc, fumes from the welding operation itself, stray sparks that can burn, and so much more. They’re an essential part of any welder’s kit, and they’re a purchase that can last for decades if well-maintained, so it’s important to put some thought into which helmet you’re buying.
So, what should you look for? What factors should you evaluate when you’re exploring welding helmets? Here’s our guide. While there’s a lot to consider, one thing is certain: you need a helmet whenever you’re welding. The only possible exception is if you’re using CNC welding machines, and they’re enclosed in their own darkening shades. Even then, it can be beneficial to keep a helmet on hand.
Prefabrication in the construction industry is likely to remain an ongoing trend. The skilled labor shortage, growing demand, and tighter margins increase the need to create the construction elements in a controlled environment.
Why is the controlled environment so important? Well, the key lies in absolute management and leaving very little to chance and environmental factors.
When elements of buildings, infrastructure, and industrial facilities are produced serially, process control and project cost efficiency increase significantly.
Can quality meet quantity? It sure can. The submerged arc welding process (SAW) is a specialized metal joining method applied when you need to weld extreme thicknesses and achieve exceptional weld quality. It offers an extremely high metal deposition rate while providing high weld accuracy, fusion quality, depth of penetration, and a low rate of weld discontinuities.
Other highly efficient arc welding processes, like MIG and Flux-cored, can’t match the deposition rate of the submerged arc welders. Heavy fabrication of structural steel, shipbuilding, and pressure vessels relies on the SAW to meet the production demand and quality expectations.
Quality assurance is a critical factor for any pressure vessel welding job. Pressure vessels pose a significant danger to everyone working or living around them, as they can explode if they aren’t fabricated to meet code criteria. Quality assurance involves weld testing to ensure the welded seams meet the requirements for a safe and long pressure vessel service life.
Pressure Vessel Fabrication and Inspection Codes
Pressure vessels, boilers, and heat exchangers are subject to welding codes and standards. All US states have legislated the requirement to manufacture pressure vessels according to the ASME code. But rules can vary from state to state, depending on many factors like climate. High/low temperatures, moisture, and marine environments influence the design and fabrication requirements, so you should always ensure you are fabricating and testing the pressure vessels to meet your local law requirements on top of meeting your client’s expectations.
ASME Boiler and Pressure Vessel Code (BPVC)
“ASME” is the name in the pressure vessel industry. But, when people say “ASME” in the pressure vessel context, they are actually referring to the American Society of Mechanical Engineers (ASME) and theirBoiler and Pressure Vessel Code (BPVC). This massive code consists of over 30 books with over 17,000 pages, but the following are the most important for welding and inspecting the pressure vessel welds:
These standards contain rules for the design, fabrication, welding, and testing of welded pressure vessel assemblies. Likewise, they contain rules for the qualification of personnel and the responsibilities and duties of authorized inspectors.
Being an “ASME code shop,” or an “authorized shop” as many refer to, simply means that you are certified to perform pressure vessel welding according to the ASME code. You would need to enter into a contract with an authorized inspection agency and have a dedicated authorized inspector. The inspector would often interact with your shop as you conduct your business producing ASME pressure vessels.
Being an authorized shop brings many benefits, including better access to the market and allowing you to stamp the ASME mark on your pressure vessels. However, this requires rigorous quality assurance for every pressure vessel to ensure a high weld quality for safety and compliance with the code.
The National Board of Pressure Vessel Inspectors
Another critical organization for pressure vessel safety isThe National Board of Pressure Vessel Inspectors. They develop standards, training programs, and certifications for the construction, installation, repair, inspection, and repair of pressure vessels and boilers.
There are also other bodies, including theAmerican Petroleum Institute, that develop codes for pressure vessel fabrication and testing. But, the ASME is the most critical code for most applications.
Quality Assurance From The Get Go
“Staying vigilant in the pre-welding phase can save significant resources and prevent rework or penalties”
Quality Assurance Plan (QAP) forms the framework for activities before, during, and after the fabrication process. So, quality is ensured from the very beginning. Some of the most critical pre-welding quality control steps are:
Verifying welder qualifications for specific weld types, materials, and positions.
Ensuring that the welding equipment is set for meeting the WPS requirements.
Reviewing WPS documents to ensure accuracy and completeness.
Conducting tests on weld coupons as needed to verify WPS qualification.
Ensuring compliance with industry standards and requirements for base metals and welding consumables.
Checking joint cleanliness and proper fit-up during the inspection process.
Verifying that joint design and weld preparation meet WPS and applicable welding standards (ASME, AWS, API).
Reviewing clearance dimensions of rings, consumable inserts, or backing strips as needed.
Staying vigilant in the pre-welding phase can save significant resources and prevent rework or penalties, depending on the situation and the job. Missing a critical error can mean a complete profit loss or worse. That’s why spotting irregularities early on is so important for long-term welding shop success, especially in the pressure vessel industry.
Welding pressure vessels involves many people: metallurgists, engineers, authorized inspectors, welding personnel, production managers, and the sales department that stands between you and the customer. So, if a critical step is missed or done incorrectly, you might get into a situation where lots of people have to re-do their jobs, inspect the newly present situation, and decide on how to proceed. This can lead to delays and profit loss, which is why quality assurance early in the process not only ensures pressure vessel safety, but hitting the deadlines and achieving the projected profitability.
Non Destructive Testing (NDT) For Pressure Vessel Welds
Welding the pressure vessel is only part of the job. Making sure those welds will actually hold is another thing entirely.
While quality assurance includes welder, welding procedure, and material qualifications, the produced welds must also be inspected.
All welds are first inspected visually. An experienced certified welding inspector (CWI) can easily spot many discontinuities and weld flaws from the visual inspection alone, which can save the effort and time of performing the NDT if the welds aren’t up to the visual standards. However, once the welds pass the visual test, they also must pass NDT tests like X-ray, ultrasound, and other NDTs appropriate for the pressure vessel at hand.
AllNDT testing should be done with aturning roll system to ensure operator safety and convenience, especially when dealing with very large pressure vessels. The operator must apply radiographic imaging, ultrasound probe, or other equipment over the circumference of the pressure vessel. But, this can require the operator to get underneath the pressure vessel or work at an awkward angle, which can be extremely dangerous with heavy equipment.Welding turning rolls allow the rotation of the pressure vessels so that the relevant part of the wall always faces the operator, ensuring easy and safe welding and testing.
Radiographic Testing
Radiographic testing is applied to all critical welds on pressure vessels, like butt and seam welds, to ensure weld penetration and quality. Radiography sends X-rays or gamma rays into the weld, creating an image that captures even the tiniest of weld defects. RT can spot voids, dents, cracks, porosity, changes in material thickness, and other weld discontinuities and defects.
Radiation is a safety hazard, and RT requires skilled technicians, but this is the most widely adopted weld NDT method that’s especially useful for pressure vessel testing. RT provides hard evidence in the form of a film rather quickly, while digital radiography can give you results on screen in seconds.
Ultrasonic Testing
Ultrasonic testing detects weld discontinuities and defects such as cracks, inclusions, and thickness variations in a pressure vessel’s material. It involves sending high-frequency sound waves into the material and measuring the time it takes for the echo to return. As these waves travel through the weld, they will reflect back some energy if they hit a weld discontinuity, which is what the operator is looking for.
UT is more challenging to perform and requires a highly skilled operator. It’s also slower than RT, but it can be a preferred method, depending on various inspection and weld factors.
Magnetic Particle Testing
Magnetic particle testing is only suitable for evaluating ferromagnetic materials. But, the equipment is inexpensive and portable. By subjecting the surface to a magnetic field and introducing magnetic particles, any defects or fissures will attract the magnetic particles. Under proper lighting conditions, even the most minuscule imperfections become visible and easily identifiable. However, operators can use fluorescent magnetic inks to improve visibility and flaw detection.
MT testing can only detect surface weld discontinuities. It’s not the best way to inspect the weld quality deep in the material.
Liquid Penetrant Testing
Liquid penetrant testing is also applied to test surface-level weld discontinuities. It’s a great way to quickly inspect for cracks, laps, cold shuts, laminations, porosity, and other weld defects. Results are very easy to read, so less operator training is required.
PT works by applying a liquid penetrant to the surface, waiting for it to penetrate into discontinuities, and removing it from the surface. Next, another substance is applied, which draws out the penetrant trapped in the cracks and other discontinuities, making them easy to spot visually.
Hydrostatic Testing
Pressure vessels, boilers, storage tanks, and piping systems are also subject to hydrostatic testing after the vessel is completed or repaired. Hydrostatic testing is performed by filling the vessel with water and pressurizing the system up to 1.5 times the design pressure limit. The water can also be dyed to help spot any leaks.
Critical Weld Defects
The NDT methods are used as a part of a quality assurance protocol to prevent critical weld defects from jeopardizing the safety of pressure vessels. Some of the most detrimental weld defects for pressure vessels are described below with their associated dangers.
Cracks – It doesn’t get worse than weld cracking for pressure vessels. Transverse, longitudinal, or crater weld cracks can propagate and lead to catastrophic weld failure and pressure vessel explosion.
Burn-through – Excessive welding current or inadequate welding speed can cause the burn-through and deterioration of the welding joint. As a result, the weld can get compromised as not enough root material is left.
Inclusions – Tungsten, flux, slag, and oxides can get trapped in the weld as inclusions and negatively affect the weld strength. They are usually easy to spot in NDT.
Excessive weld reinforcement – A highly problematic weld discontinuity because it can cause stress concentration at the toe of the weld, leading to an increased chance of weld rupture.
Incomplete fusion and incomplete penetration – Both are severe weld defects that can lead to pressure vessels being unable to withstand operating pressure, causing failure and explosion.
Porosity – Usually caused by inadequate shielding from the gas or flux or from the shielding agent contamination. Weld porosity manifests as trapped bubbles deep in the weld or on the surface and weakens the weld’s integrity.
Overlap – A condition where a weld metal extends beyond the weld toe or root without fusing and creates a mechanical notch parallel to the weld. This is a serious issue that usually calls for weld rejection. Overlap usually means weak fusion, which is a big problem for vessels experiencing pressure and temperature swings.
Undercut – Occurs when the weld face or root surface is below the adjacent base metal surface, which can significantly weaken the joint.
Red-D-Arc – Your Trusted Partner For Industrial Welding
Whether you repair or manufacture pressure vessels or are considering venturing into this highly lucrative industry, we have the equipment you need. Pressure vessel fabrication requires specialized turning rolls,fit-up bed equipment, seam welders, andwelding manipulators in order to achieve maximum productivity and fast turnaround times.
Contact us today, and our team of experts will help you choose the most appropriateweld automation equipment and power sources for the job you are looking to bid or take on.
Cast metals have a lot of benefits over more common versions of those same metals. Cast iron has better thermal conductivity than standard iron. Cast steel is stronger than mild steel. The secret – increased carbon content – increases durability and changes the material properties of the metal, but it comes with a cost. Cast metals are wear-resistant, strong, and easy to produce. As a trade-off, they’re more brittle, and when they break, they crack and fracture, rather than bending or warping. This also makes them much harder to repair via welding, and it’s generally very difficult to weld a piece of cast metal, either to another piece of cast metal or to another kind of metal entirely.
Difficult, but not impossible!
Welding cast metals is one of the more significant challenges that a welding operator is likely to face in their career. It’s difficult enough that simply applying your normal techniques and hoping to wing it on the fly is going to leave you with a worse mess than where you started.
So, how can you weld cast metals? What considerations do you need to keep in mind? Let’s talk about it.
Preheating is familiar to anyone who cooks or bakes, and it’s rare that a recipe doesn’t start with “preheat your oven to X temperature.” In welding, though? Preheating may seem like a more alien concept. Some welding operators go their whole careers never having needed to preheat a weld, while others preheat everything they handle.
So what is preheating, how does it work, why is it necessary, and when should you use it? Let’s answer these questions and more.
Underwater welding is an extremely challenging, technical, and complex task. It’s also extremely dangerous. Welding has many dangers of its own, from fumes to UV rays to the fire and shock hazards of sparks and arcs; add to that doing it all underwater and you can see why it’s an extremely specialized task.
Yet there are always people who will seek it out as a profession. Why? The $200-$300k per year take-home is certainly a draw.
The reality is that those numbers are on the high end, for a skilled and lucky underwater welder. Since underwater welding pays by the project, not as a steady salary, it’s very inconsistent. A single project could be worth $30,000 and take a few days or weeks, but it might be months in between projects. Aggressive and skilled welders can find more frequent work, but that’s not always easy.
And, of course, there’s a lot of difference between rookies and veterans, inland and offshore, and other variations in the career. There are even bonuses based on depth; the deeper the project is underwater, the more dangerous it is, so the more pay is involved. Still, it’s a significant draw for many who love both welding and diving.
There are only a few factors you can control when welding, and one of the easiest and most impactful is the speed at which you travel across a joint to fuse metals together.
Known simply as “welding speed,” the travel speed heavily impacts the resulting quality of the weld. It also impacts the risk of distortion in base materials and the stress resistance of the finished product.
Dry ice blasting is a state-of-the-art cleaning method that can save time and money — typically the cleanup can be accomplished in one third the time of traditional cleaning methods and, even more important, the cleaning job is more thorough, especially in hard to reach places.
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Welding Protocols and Quality Assurance in Aerospace Construction
Aerospace construction is an environment where the role of welding cannot be overstated. It requires precision, skill, and a great understanding of the industry-specific challenges and requirements to provide safety and reliability.
This article explores aerospace construction, taking a look at the welding protocols and quality assurance that are required in every project.
The Importance of Welding in Aerospace Construction
Welding is more than just joining materials in aerospace construction. It constitutes a critical discipline, integral to the engineering of aircraft and spacecraft where precision is paramount, and the stakes are high. Here, every weld must embody a blend of science and skill, contributing significantly to the final masterpiece that takes to the skies.
Criticality of Precision Welding
The margin for error is non-existent in the aerospace sector. Every weld must be executed with the utmost precision. They play a crucial role in the structural integrity and resulting performance of components. Precision welding ensures that each weld can withstand extreme conditions, from the rigorous demands of high-altitude flying to the intense pressures and temperatures of space travel. Therefore, the skill and expertise required in aerospace welding are of the highest caliber. They must guarantee that every component contributes to the safety and reliability of the final construct.
Selecting Materials and Techniques
Due to the unique demands of aerospace construction, there is a requirement for specialized materials. Titanium and aluminum alloys are common as they’re lightweight yet extraordinarily strong. Every material used can pose unique welding challenges due to the fact they have distinct properties. Welders must be aware of these properties and apply suitably advanced and precise welding techniques. They must be tailored to the specific material’s thermal and structural properties to ensure the required integrity and functionality.
Aerospace welding adopts many techniques to meet the industry’s demands. TIG (Tungsten Inert Gas) and MIG (Metal Inert Gas) welding are the most prevalent. TIG welding is favored in aerospace for its precision and superior weld quality. This makes it ideal for use with the thin and lightweight materials commonly used in aircraft and spacecraft.
MIG welding is preferred for its efficiency and the strength of the welds it produces. This is especially beneficial when working with materials that are a bit thicker. Both these methods require welders who understand the materials so that the welds can be strong, light, and flawless.
Quality Control and Safety Standards
Safety implications are immense in welding construction. There is a necessity for quality control processes, where every weld must adhere to rigorous safety and performance standards. The smallest flaw can have catastrophic consequences in aerospace; therefore, the level of scrutiny must extend beyond the weld itself. This encompasses everything from the inspection of materials and the verification of welding equipment to the certification of welders.
Quality Assurance Measures in Aerospace
Rigorous quality assurance measures are essential in providing safety and precision in aerospace welding. A comprehensive set of practices and testing must be followed to ensure the integrity of each weld. This includes advanced non-destructive testing (NDT) methods. These are an integral part of weld testing that identify potential flaws that could compromise the safety and functionality of aerospace components.
At the forefront of these NDT methods is radiographic (X-ray) inspection and ultrasonic testing. Radiographic inspection uses high-energy radiation to capture an image of the weld. This then reveals cracks, voids, and other internal flaws. Ultrasonic testing employs high-frequency sound waves through a weld to detect imperfections. They will reflect back any flaws to create a detailed internal structure picture of the weld.
There are also destructive testing methods that the aerospace industry draws upon. These methods include tensile testing, bend testing, and fracture testing. They’re used to evaluate the weld’s strength, ductility, and other physical properties. To conduct these tests, the breaking or deforming of a sample weld will occur to better understand how it performs under a variety of stress conditions.
These quality assurance protocols are also integral in enhancing future welding processes. The feedback and data from these tests can contribute to refining techniques and protocols. This reflects the industry’s relentless pursuit of perfection.
Red-D-Arc’s Expertise as a Welding Equipment Supplier
Red-D-Arc offers years of experience and deep-rooted knowledge in supplying welding equipment to manufacturers across a wide range of industries. We have established ourselves as a trusted partner in the industry for our arsenal of welding solutions.
Our range of equipment includes a number of advanced TIG and MIG welders, specifically designed to cater to the strict requirements of aerospace construction. From theMiller Syncrowave 350 LX to theMillermatic 350P Aluminum Push-Pull Gun System, our machine rentals are renowned for efficiency and capable of delivering high-quality welds at a pace that keeps your projects on schedule.
Reliability is a cornerstone of Red-D-Arc’s offerings. We ensure that every piece of equipment we offer operates at peak performance with minimal downtime. This sort of precision is critical in an industry where even the slightest error can have significant repercussions.
Collaboration is key in Red-D-Arc’s approach to the industry. We work closely with our aerospace clients to deliver the most effective solutions for your project needs. By blending our expertise into the early stages of your project, we can help navigate the complexities of aerospace welding. We will identify the best techniques and equipment for each of your aerospace endeavors.
Elevate Your Aerospace Projects: Connect with Red-D-Arc Today
If you’re facing the challenges of aerospace welding and require experience, look no further. Red-D-Arc is your go-to solution for precision equipment.
Contact us today to discuss how our welding equipment and expertise can help advance your aerospace construction projects. Our team is on hand to provide the insights and equipment you need to ensure your project’s success from the initial stages to success.
Welding aerospace parts and structural elements requires a lot of skill due to stringent industry standards and challenging specialized materials. Aircraft and spacecraft rely on materials like titanium, nickel superalloys, special aluminum types, beryllium, and specialty steels. Almost every aerospace material requires a specialized approach because the welding process can negatively alter the properties of these metals and lead to many weld discontinuities and defects.
What Makes A Good Aerospace Material?
Aerospace materials must tick several critical boxes, including but not limited to:
High strength. All materials used in aircraft must be able to withstand the forces they are subjected to. Tensile, compression, shear, and torsional forces can be extreme in aircraft, requiring the application of exceptionally strong materials.
Long-term reliability and high resistance to corrosion and fatigue cracking.
Low weight. This is essential for aircraft fuel economy. Every aerospace manufacturer prioritizes reducing weight as it’s the most critical aspect of an aircraft’s cost-effectiveness.
Low thermal expansion. Cooling and heating cause materials to shrink and expand, leading to cyclical thermal stresses in critical aircraft and spacecraft parts.
Good weldability. Metals used in the aerospace industry often require welding with specialized processes. The easier the material is for welding, the better. But, this is hardly ever the case with aerospace materials.
Aerospace materials directly influence the initial and ongoing costs of an aircraft, fuel economy, design options, speed and range of an aircraft, safety, recycling, and even the passenger’s comfort.
Just to name one example of how material selection can alter the characteristics of an airplane, we can look at how aluminum use influences passengers’ experience. Humidity must be intentionally lowered during flight to prevent aluminum oxidation if the airplane uses aluminum for structural materials. As a result, passengers may get dehydrated on long flights and have a less convenient flight. So, seemingly unrelated phenomena like using aluminum in the airplane can have unexpected outcomes. The importance of alloy selection for any aircraft cannot be overstated, as all metals have pros and cons that must be carefully weighed.
When engineers design aircraft, they must consider a vast array of problems and choose materials to meet the most critical demands of the aircraft. However, welding technologies and the weldability of the materials play a crucial role in alloy selection.
Welding Aerospace Materials – Challenges And Solutions
Welding codes and aerospace industry standards require exceptional weld quality in almost all welding applications, especially critical parts. Landing gear, structural elements, fuel tank, exhaust system, and fuel and hydraulic lines must be welded with utmost quality. There is no room for error. Meticulous non-destructive testing (NDT) can spot all weld flaws, usually prompting rework.
Such stringent requirements paired with highly exotic alloys that do not respond well to high heat make welding in the aerospace industry very challenging. However, every problem has a solution. There is always at least one welding process that can be configured to meet the demands of almost any alloy in the aerospace industry.
Aluminum
Aluminum has been the top choice for most aerospace applications ever since it superseded wood in the 1920s/1930s. The first aluminum alloy used for aircraft was Duralumin. Today, modern aircraft rely on far more advanced and highly specialized aluminum alloys for excellent structural integrity, recyclability, and low cost and weight.
While aluminum does pose challenges like oxidation, as we mentioned earlier, it’s still a highly relevant material for commercial, military, and private aircraft. Aluminum has excellent machineability, long fatigue life, high damage tolerance and facture toughness, and a good corrosion resistance.
There are many aluminum alloys in the aerospace industry. Some alloys can be fusion welded, while others require friction welding and other specialized welding processes. For example, the most commonly used aluminum alloys for aerospace structural components are the 2000 and 7000 series aluminum, which usually require friction stir welding.
Aluminum alloys like 1000, 3000, and 5000 are also frequently used in aerospace construction for wing ribs, stiffeners, tanks, framework, ducting, flaring, wheel pants, nose bowls, cowlings, fillets, oil tanks, and other important aircraft parts. These alloys can be fusion welded using the MIG and TIG welding processes.
TIG welding aluminum produces the best fusion welding results. The TIG welding process allows precise heat input control, filler metal addition, and weld accuracy. This welding process is also exceptionally clean, with a minimal chance of inclusions.
Aluminum has a surface oxide layer that melts at a significantly higher temperature than the base metal underneath. This is one of the biggest challenges when welding aluminum. However, this problem is eliminated when using advanced AC TIG power sources. The positive side of the alternating current breaks the oxide layer, while the negative side melts the base material. High-end power sources give you precise control over the AC balance and individual amperage values for cleaning and penetration sides of AC TIG. The best example is theMiller Dynasty 400 AC/DC TIG welder with its extensive array of highly customizable functions.
Welding aluminum for aerospace applications also benefits from pulsed AC TIG and multiple waveform selection. Aluminum can easily warp due to excessive heat input, but applying a correct pulsed waveform can make distortion less likely to occur. This is critical for the aerospace industry, where distortion tolerances are minimal.
Magnesium
Magnesium is 33% lighter than aluminum, making it one of the lightest structural metals in use today. However, magnesium isn’t used in significant quantities in aircraft due to its high cost and lower stiffness and strength compared to aluminum. It used to be one of the most commonly used materials for aircraft in 1940s and 1950s, but aluminum has superseded it in many applications.
Today, magnesium is still used for gearboxes and gearbox housings of aircraft, covers of components, electronic housings, flight control systems, aircraft wheels, and the transmission housing of helicopters. While aluminum is less costly and can have higher strength, magnesium’s low weight and excellent machineability make it an irreplaceable material for certain commercial and military aircraft parts.
Welding magnesium for aerospace applications often requires the friction welding process. However, less critical aerospace parts can be fusion welded with TIG and MIG. This is especially the case when repairing aircraft parts and engine castings.
Welding castings from magnesium requires high expertise. Magnesium is flammable, castings can soak in oil (which can significantly impact the weld quality), and magnesium alloys can contain zinc (which evaporates and can cause porosity).
Like aluminum, magnesium has oxides on its surface that must be removed before welding. But, AC TIG can significantly reduce the chances of oxide inclusion when set correctly.
The MIG welding process can often be a better choice for magnesium, depending on the welded part. When repairing a thick magnesium piece, MIG’s high heat and deposition rate is beneficial. Since magnesium conducts heat rapidly like aluminum, you need more heat to keep the puddle going, and this is especially the case with thick casting walls.
However, like aluminum, magnesium filler metal wire is much softer than steel wire, which requires using a specialized wire feeding system. This is where advanced aluminum and magnesium MIG welding systems come in.
TheMiller AlumaFeed Synergic aluminum MIG welder coupled with the Miller XR-Aluma-Pro Push-Pull gun, offer a seamless MIG welding experience with soft filler materials with advanced arc output control. With up to 900 inches per minute wire feeding speed and up to 425A output, you can weld most aluminum and magnesium thicknesses with high efficiency. In addition, Miller’s Profile Pulse allows you to achieve a TIG-like weld appearance using a pulsed MIG welding process.
Titanium
Titanium is the holy grail of metals. It’s the most critical material in the aerospace industry thanks to its incredible strength, low weight, excellent corrosion resistance, and ability to retain its mechanical properties under high temperatures. Titanium ticks all boxes except price, so its applications are limited to critical aircraft parts like airframe structures and jet engine components.
Titanium aircraft can withstand supersonic speeds higher than Mach 2. Aluminum becomes soft when exceeding Mach 1.5 due to friction between the airplane skin and the air. Titanium was the material USAF used to develop and construct the SR-71 Blackbird in the 1960s, allowing this engineering marvel to reach speeds above Mach 3. No other material could provide the necessary strength and heat resistance for the most sophisticated and fastest aircraft of all time. On its last flight in 1990, the SR-71 Blackbirdset a speed record by flying from Los Angeles to Washington, D.C. in 64 minutes and 20 seconds. Titanium’s contribution to the speed of modern aircraft cannot be overstated.
Today, military aircraft, like the famous F-22 Raptor, still utilize titanium alloys in far greater quantities than commercial aircraft. That’s because titanium structural members can withstand extreme loads generated by air maneuvers that jets must be able to handle. But, titanium is an irreplaceable material for all aircraft and spacecraft. Commercial airliners, helicopters, military jets, drones, and other aircraft rely on titanium’s strength for structural members and low weight to improve their range and fuel economy.
Welding titanium is challenging because this material quickly oxidizes at high temperatures and requires exceptional weld cleanliness and purity. High weld accuracy and impeccable arc stability are non-negotiable when working with titanium in the aerospace industry.
Pure commercial titanium, alpha and near alpha, and some alpha-beta alloys are weldable, while some alpha-beta titanium alloys are very challenging to weld. However, the extremely strong alpha-beta titanium alloy Ti-6Al-4V is weldable, which is one of the reasons it is commonly used for aerospace structural components.
Welding titanium requires meticulous care in ensuring the shielding gas coverage. Not only does the weld pool need to be protected with argon gas, but you also need a trailing shielding gas coverage to protect the weld as you move along the joint. Since titanium is highly reactive with oxygen at elevated temperatures, it’s critical to ensure that the welded joint is covered with a shielding gas as it cools. One of the best indications of an overly oxidized titanium weld is discoloration, which is why AWS D17.1 requires discolored titanium welds in a range from violet to white to be rejected. Overly oxidated titanium welds become brittle and cannot withstand the forces exerted on the aircraft’s structural members or engine components.
Pulsed TIG can help prevent oxidation by reducing the heat input. The lower the heat, the lesser the chance of titanium to react with the oxygen in the atmosphere. This is again where advanced TIG welding machines, like theMiller Dynasty 400 AC/DC, can save the day. The Dynasty can output up to 5000 pulses per second in DC TIG, giving you better control over the heat input and reducing the chances of titanium oxidation. Likewise, using such extreme pulse speeds concentrates the arc, allowing higher travel speed, which again reduces excessive heat input.
One particular benefit of high pulses per second when welding sluggish materials like titanium is breaking surface tension through arc pulses. This can sometimes help eliminate porosity and improve puddle wetting.
Superalloys
Titanium can operate at high temperatures and retain its properties, but its limit is at about 1100°F (600°C). On the other hand, the temperatures in jet and rocket engines reach far higher temperatures of up to 3100°F (1700°C). The need for materials that can withstand these extreme temperatures led to the development of nickel, iron-nickel, and cobalt superalloys.
Superalloys are some of the greatest human inventions yet. Nothing like them exists in nature. These materials retain all of their mechanical properties in brutal conditions at extreme temperatures where jet fuel meets air, pressure, and fire, resulting in combustion that would melt or negatively influence pretty much any material known to us. The development of these alloys has allowed engineers to dramatically raise the thrust power of jet-powered engines, resulting in far greater speed and significantly lower fuel consumption.
Superalloys are usually named by the company that developed them. The most critical nickel superalloy used in jet engines is the Inconel 718. Other examples include Hastelloy X, Inconel 625, Inconel 901, Rene 95, and Discaloy.
All superalloys contain a very carefully selected mix of alloying elements that can include niobium, yttrium, cerium, ruthenium, platinum, iridium, zirconium, titanium, tantalum, tungsten, and many other rare-earth materials.
Welding superalloys is challenging because it’s extremely important not to negatively alter the material in the weld zone and heat affected zone (HAZ). Some of the biggest welding challenges are:
Alloying elements with a low melting point can cause embrittlement. Lead and sulfur are a good example.
Cracking due to stress concentration in the HAZ.
Incomplete fusion.
Carbide precipitation and subsequent crack development.
Successfully manipulating the weld metal. The challenge is the sluggishness of nickel alloys, which makes welding accuracy difficult.
Excessive heat input can cause harmful metallurgical changes, resulting in weld cracking and loss of corrosion resistance.
The TIG welding process can produce excellent results when welding many aerospace superalloys, particularly with the Inconel 718 and similar superalloys with excellent weldability. Of course, like with all aerospace alloys, the welding process selection depends on many variables, not limited to the application.
AdvancedTIG welding power sources can make welding superalloys less challenging thanks to high-end features that allow maximum arc control. For example, pulsed DC TIG can help reduce excessive heat input and improve the solidification structure and tensile properties of the weld. Nickel and cobalt superalloys are very sensitive to the welding approach, which is why it’s critical to use a TIG power source that has an extensive array of settings.
Sometimes, the difference between an inspection-passing weld and a flawed weld is just about micro adjustments on the power source. This is particularly true when using pulsed TIG, as high pulses per second can make it far easier to weld highly sluggish nickel alloys. Nickel alloys aren’t as fluid as steel when in the molten state. So, high arc pulses can help break their surface tension and settle the weld better by agitating the puddle. But, to maximize this effect, the pulse settings must be set according to your travel speed, the alloy type, thickness, and desired weld profile.
Specialty Steels
The aerospace industry wouldn’t be complete without steel. But, not all steels can meet the criteria for aircraft and spacecraft. The steels used are usually about two times the strength of titanium and three times stronger than aluminum. However, as strong as specialty steels can be, there is no getting around their excessive weight. So, high-strength steels are only used for about 5-10% of aircraft’s structural elements. Steel application is usually limited to critical elements like landing gear and wing box components.
The three most commonly used steel types in the aerospace industry are:
Maraging Steel – This is a unique steel type with exceptionally low carbon content but incredibly high strength, ductility, and fracture toughness. Maraging steel is one of the strongest metals ever discovered, and it’s often used for heavily loaded aerospace components.
Precipitation Hardening Stainless Steel – PH stainless steel is corrosion resistant and very strong, making it an excellent choice for applications where these properties are critical.
Medium Carbon Low-Alloy Steels – These steel types contain between 0.25% and 0.5% and various alloying elements to increase hardness and high-temperature strength. They are typically used for undercarriage parts.
These specialty steels are best welded with minimal heat input and high travel speed. For example, Maraging steel should not be held at elevated temperatures for a long time. While these materials can be MIG welded, TIG welding again produces a better result due to its clean nature. Still, pulsed MIG can be more favorable in some applications for productivity gain.
Specialty steels may require post-welding heat treatment (PWHT) and specific interpass temperatures to be maintained, depending on the alloy and application. Whenever the work requires precise temperature control, we recommend theMiller ProHeat 35 induction heating system. Induction heating heats the material from within, resulting in high efficiency, ease of setup, maximum temperature control, and uniform heat treatment.
Red-D-Arc – Your Source For Specialized Welding Equipment
The number of materials in the aerospace industry is enormous, and each requires a different welding approach. Even composite materials rely on welding for mold fabrication and repair. Our team of experts can help you choose and optimize the most suitable arc welding process for fusion welding of aerospace parts, whether you are a small repair shop or a large contractor in the aerospace industry.
We have a massive fleet of specialized welding equipment for all industries, and aerospace is no exception.Contact us today to learn more about our advanced MIG and TIG power sources and how we can help you meet your client’s expectations.
While many welding machines have ratings that tell you the maximum thickness of the material they can weld, you’re more often going to encounter the opposite problem: material that is too thin.
It’s not that a welding machine has trouble fusing pieces of thin material. In fact, it’s too easy, which is why it’s actually very difficult. Linger too long, and you melt right through the material, leaving a hole rather than a seam. You fail to manage your heat properly, and a nice flat workpiece warps and waves with thermal expansion and contraction. It’s extremely easy to do wrong in a way that can ruin a workpiece and force you to start from scratch.
So, how can you learn to weld thinner materials properly without burn-through or other problems? Read on for our expert tips and advice.
Here at Red-D-Arc, we talk a lot about welding, the act of taking two pieces of material and joining them together. Often, though, you aren’t just welding; you’re separating materials, whether to fix a mistake, to disassemble scrap, or to fabricate smaller parts used for later welding purposes.
There are plenty of different ways to cut apart materials, even metals. There are saws, grinding wheels, shears, and other machines that can near-effortlessly slice through all but the strongest metals. With modern technology, though, two techniques stand out: plasma cutting and laser cutting. How do these two work, how do they compare, and which is better for a given purpose? Let’s analyze them and find out.
How Laser and Plasma Cutting are Similar
First, let’s start with the similarities between laser and plasma cutting.
Primarily, the similarity is in the mechanism they use to cut materials. They are both known as “thermal cutting” methods, which means they use high, intense, directed heat to melt/burn through material, leaving a gap that becomes a cut. This is opposed to more mechanical methods, where friction or gouging is used to remove material.
Both plasma and laser cutting are powerful tools and are well-suited to precision applications. They are ideal for computer-controlled guidance, particularly programmed CNC cutting. This is how many complex, bespoke shapes are cut from materials and how vast amounts of repeated fabrication can be performed rapidly.
While both work in similar ways and can serve similar purposes, there are some distinct pros and cons of each method that can make one more ideal than the other in specific circumstances. Let’s dig deeper.
What is Plasma Cutting, and How Does it Work?
Plasma cutting may seem like some futuristic technology, but in truth, it was first invented back in 1957. In the subsequent 60+ years, many advancements have been made to the technology, both in plasma cutting itself and in the surrounding mechanisms like computer and robotic controls.
How does it work? In prosaic terms, it can be described as capturing a tornado in a torch and electrifying it. Essentially, an electric arc is generated by a cutting torch. Meanwhile, a particular kind of gas, usually an inert gas like argon or nitrogen, is pushed through the torch in a spiral. The gas passes the arc and becomes electrified and ionized while also heating it to a temperature as high as 20,000 degrees C. Scientifically speaking, it’s no longer even gas but the fourth high-energy state of matter, plasma.
This superheated ionized gas/plasma is then pushed out of the torch by the pressure of the gas behind it and its own thermal expansion. This gas is directed and focused on the specific narrow area where you want to cut, and it rapidly melts the material in that area. The force of the gas blows away the molten material, leaving a void and cutting through the workpiece.
One of the biggest caveats to plasma cutting is the electrical arc. This arc, much like arc welding, is generated by the connection and short-circuit between the torch and the workpiece. As a consequence, only conductive metals can be cut with plasma torches. It’s excellent for cutting steel, aluminum, brass, or copper but doesn’t work on materials like wood, ceramic, silicon, or plastic.
What is Laser Cutting, and How Does it Work?
Lasers have been part of public consciousness for decades, and while using high-powered lasers for cutting and other purposes has been the realm of science fiction for a very long time, the reality is that they’ve also been usable as tools since 1965. This makes them only slightly newer than plasma cutters.
Laser cutting is, on the face of it, very simple. A laser itself is just light, concentrated, and focused. The way that light is generated, directed, and focused may vary. Common lasers include CO2, Neodymium, and fiber laser systems, with varying power ranges and usability. Simple weak lasers can be the size of a battery and are used to play with cats; meanwhile, the most powerful laser in the world currently is theVulcan 20-20, which is capable of generating a laser with 20 petawatts of energy. Obviously, this is not for use as a cutting tool but rather as a research device.
Fiber lasers, crystal lasers, and other kinds of laser generation systems have their own kinds of pros and cons, but for the most part, they are used in very specialized use cases or in research and scientific experimentation rather than for simple industrial cutting and fabrication. This is because they tend to be larger, more fragile, much more expensive, more elaborate, and prone to failure, and generally don’t have the benefits to outweigh those drawbacks.
The majority of the time, a laser you get for production cutting will be a CO2 laser. In these lasers, a mixture of gasses, including CO2, helium, and nitrogen, is contained in a vessel. This gas mixture is stimulated with an electrode, which excites the CO2 molecules and causes them to emit photons. With enough CO2, this process generates enough photons to create a high-energy laser capable of cutting.
Unlike plasma cutting, laser cutting can be precisely tuned and can be used for cutting, engraving, surfacing, and other finishing. It can cut conductive materials like steel, brass, and aluminum, but since it doesn’t require an electrical connection with the workpiece, it can also cut nonconductive materials like wood, silicon, ceramic, and more. It can also cut metals that are more difficult to cut using plasma, like tungsten and nickel.
So, how do the two kinds of cutting tools compare?
Comparing Plasma and Laser Cutting Tools
Let’s run down a variety of considerations and compare laser and plasma cutters along each axis.
Accuracy
Laser beams can be very concentrated and precise. This makes them much more accurate in general than plasma cutters, which are comparatively high energy and less focused. Plasma cutters tend to have a larger kerf for the cut, meaning they leave a larger hole in the material and have less precision.
Since they remove more material, they also create more residue and slag than laser cutters. Lasers are better for precise and delicate tasks, as well as non-cutting uses like engraving.
Flexibility
Laser cutters, as a form of directed energy, can cut anything that absorbs photons. Plasma cutters, since they rely on electrical conduction with the workpiece, can only cut conductive materials. The disadvantage of laser cutters here is that some metals are highly reflective; they don’t absorb much, if any, photons, so they are very difficult or impossible to cut using lasers, which are essentially reflected away from the material.
Another area where plasma cutters surpass laser cutters is in cutting thick materials. Most common laser cutters can only cut materials up to about 19mm thick with reasonable speed, accuracy, and efficacy. Meanwhile, plasma cutters can easily cut through materials up to 38mm thick without issues.
That said, more powerful lasers can do much more. Strong lasers exist that can cut through pretty much anything, no matter how thick it is, and can even cut materials from over a mile away. These are, obviously, not practical; they’re more being developed as military weaponry and scientific experiment equipment than manufacturing tools.
Plasma cutters follow the same basic design as welders. In fact, many advanced welding machines can also do plasma cutting with the flip of a switch. In contrast, laser cutting is almost always handled using a robotic CNC machine, and there are virtually no handheld laser devices. Things like this are the closest you can get, and they are designed for engraving, not cutting.
Energy Efficiency
Lasers are faster at cutting most materials and use less energy to cut an equivalent piece of material, which makes them a more energy-efficient option.
Many consider laser cutters to be better for the environment than plasma cutters for this reason.
Cost
Cost is one of the biggest differentiators between laser and plasma cutting.
Laser cutters are typically expensive. The most simple, low-powered, hobby-grade machines can range between $500 and $4,000; meanwhile, industrial-use laser cutting systems can be as much as $200,000. The sky is also truly unlimited; as linked above, the massive research laser costs billions.
Plasma cutters are often somewhat cheaper to get started. Introductory-level handheld plasma cutting systems can be as little as $200-$300. Much larger systems, including industrial CNC machines, can be between $5,000 and $20,000. Past a certain point, as well, you’re paying more for the surrounding robotics and other equipment than for the plasma cutter itself.
Operating costs, however, swing back in the favor of lasers. Despite the higher outlay, laser cutters cost less in terms of energy to operate, and they have virtually no consumables compared to plasma cutters. Plasma cutters require more energy for comparable cuts, and they require consumables in the torch and the gasses used to generate the plasma.
Safety
As with any application of high energy, safety can be a primary concern. Both laser and plasma cutting use high heat and energy to cut materials, which can lead to molten metal or other materials spattering around, sparks showering the area, and fumes generated by burning material in the air.
Plasma cutting is worse than laser cutting in two regards.
The first is that because it uses a shielding gas to generate plasma, in addition to the usual fumes, your machine is also putting that argon, helium, nitrogen, or whatever else into the atmosphere. This is an additional potential hazard, and while these gasses aren’t directly toxic, they can cause problems with oxygen displacement and other hazards.
The second is radiation. The high-energy generation of plasma sheds a high amount of radiation into the atmosphere surrounding the cutting application. This isn’t an extreme hazard akin to Chornobyl or anything, but it’s still a potential danger, especially to long-term users. It can also damage eyesight and cause surface burns to skin akin to sunburn. On top of that, this radiation can cause interference with electromagnetic signals like radio, WiFi, and other technologies and can damage nearby electronics.
Many of these hazards can be addressed. Proper use of PPE, along with the facility using proper ventilation, fume extractors, downdraft tables, and other equipment, can make it much safer to operate.
Additionally, the use of CNC and robotic machines to perform operations rather than using handheld operations manually improves safety dramatically. Enclosing a workpiece in a machine with ventilation and shielding is always safer than performing the task by hand.
Other Kinds of Cutting
There are, of course, a variety of other cutting methods beyond just plasma and laser cutting. Vaporization cutting, thermal stress cracking, reactive cutting, waterjet cutting, and oxyfuel cutting are all potential options depending on the kind of fabrication you’re doing, the precision and thermal needs you have, and how repetitive the cuts you need to make.
If you have questions about them, feel free to ask in the comments.
Which is Better: Laser or Plasma Cutting?
At the end of the day, both laser and plasma cutting have benefits that make it unclear which one is truly better. Laser cutting excels at precise cuts and the ability to cut materials that aren’t conductive metals. However, the initial expense is higher, the lack of handheld flexibility makes it worse for one-off jobs, and the comparative inability to cut thicker materials can be a significant hindrance.
Plasma cutting, meanwhile, is a cheaper and easier-to-use process, and there’s a perfectly viable option to get welders who can also do plasma cutting quickly and easily. While it can be more hazardous to the safety of the operator, it can also be automated, but the flexibility and relatively inexpensive nature of the machinery make it ideal for smaller and mid-size shops that don’t need large fabrication banks.
When it comes right down to it, though, it depends on what you need to cut, how often you need to cut, and if you need additional features like engraving or welding. You’ll simply need to evaluate your circumstances to determine which is the better investment.
That said, if you need handheld plasma cutting, we’re here for you. Our range of rental equipment includes a variety of plasma cutters at various levels of power and capacity. You can rent and try out plasma cutters and decide from there if they can do what you need or if you should explore laser-cutting options instead.
If you’re not sure which you need, you can always contact one of our experts! We’re standing by to help you out with your next project.
Welding is a critical component of productivity and safety within the petrochemical industry. The effective training and best safety practices employed by welders can often delineate the fine line between operational excellence and potential safety hazards. The importance of welding integrity and expertise plays a pivotal role in ensuring safe and productive petrochemical operations.
This article explores the importance of welding integrity within petrochemical facilities, emphasizing the best practices for safety within these facilities to ensure the safety of all.
“Welding Pipe” encompasses many applications ranging from small-diameter sanitary tubing to large-diameter pressure vessels. Some applications are more accessible to automate than others, but many difficult-to-automate applications can still be assisted by some degree of mechanical integration into the pipe welding process (mechanization).
Welding plays a key role in ensuring the safety and airworthiness of all aircraft. A single weld failure can lead to fatal crashes, carbon monoxide poisoning, loss of control over an aircraft, and the inability to land or take off. That’s why numerous institutes and legislative bodies demand adherence to some of the most stringent welding codes and standards in the welding industry.
While codes and regulations require exceptional weld quality, there is an inexhaustible number of welding challenges when working on aircrafts. From sensitive alloy welding to the issue of tight spaces, achieving what codes demand in a productive manner is anything but easy. Add in a massive demand for aircraft manufacturing and the skilled labor shortage, and it becomes increasingly more challenging to meet the code criteria and client expectations.
Welding Applications In the Aerospace Industry
Welding is applied to every aircraft, whether commercial jet airliner or rocket. Helicopters, airplanes, unmanned drones, space vehicles, military jets, and guided missiles all require extensive welding applications with the utmost weld quality.
Everything from the aircraft’s structural elements to engine parts, exhaust system, hydraulic and fuel lines, and fuel tanks requires the application of various welding processes. Even composite elements of an aircraft rely on welding for making and repairing molds. Aircraft and spacecraft use some of the most challenging to weld materials, including titanium, aluminum, magnesium, specialty steels, tungsten, beryllium, copper, and specialty nickel alloys. All of these materials are difficult to weld and require a specialized approach, especially considering the need to meet code criteria.
Aerospace Welding Standards
Aerospace welding codes and standards require impeccable weld quality with minimal tolerances for weld discontinuities and no tolerance for critical discontinuities. For example, AWS D17.1 Specification For Fusion Welding For Aerospace Applications requires welds (class A, B, and C) with no cracks, overlap, incomplete fusion, and incomplete penetration (groove only), and specifies strict acceptance criteria for other discontinuities like porosity, inclusions, and undercut. It’s extremely difficult to produce welds that meet AWS D17.1 requirements, but exceptional weld quality is one of the reasons why it’s safer to travel by plane than by car.
Aerospace manufacturers usually have to meet many codes and standards and receive certificates and accreditations from various bodies to get the best jobs and provide exceptional weld quality. The most important aerospace welding codes are:
NADCAP also plays a critical role in aerospace manufacturing. The National Aerospace and Defense Contractors Accreditation Program (NADCAP) is administered byThe Performance Review Institute (PRI). NADCAP is an industry-managed approach to conformity assessment that brings together technical experts to establish requirements for approval of suppliers using a standardized approach. Being an approved NADCAP welding facility is vital for access to the aerospace manufacturing market. However, passing NADCAP reviews and audits requires exceptional performance and produced quality. NADCAP doesn’t just audit the end result, but every employee at every touchpoint, including the process of X-ray radiography, liquid penetrant testing, material selection, outsourcing, documentation, operator consistency, and other hands-on and abstract elements of the production process.
You will likely need NADCAP approval, even if you aren’t running a large manufacturing facility. Any business that provides parts or services to aerospace manufacturers who are NADCAP subscribers may require NADCAP audits.
Other prominent organizations and agencies in the aerospace industry are:
Likewise, if you are a supplier to large aerospace manufacturers like Boing, Airbus, Aston Martin, Rolls Royce, and similar brands, you may also need to meet their specific criteria.
Welding in the aerospace industry is challenging because welds have to pass stringent testing and meet the requirements of many stakeholders. This cannot be achieved with subpar welding equipment, especially not at the scale required by the industry today. Considering the task’s difficulty, using highly specialized, feature-rich, and reliable welding equipment is critical for achieving the needed weld quality and productivity goals.
Welding Processes Used In Aerospace Manufacturing
Aerospace welding is mainly performed using the TIG, MIG, resistance, laser, and friction welding processes. These welding technologies have many differences, advantages, and disadvantages. So, choosing a suitable welding process requires meticulous research, planning, and analysis in order to achieve the most efficient production. The three primary deciding factors are the productivity goals, required weld quality, and the specifics of the welded aerospace parts.
TIG Welding In Aerospace
The TIG welding process is critical for high accuracy and high purity welds on exotic alloys like titanium, aluminum, magnesium, and nickel alloys. Since the tungsten electrode never touches the welded part, the process is extremely clean. The welding arc melts and fuses the material, and there are no slag or electrode inclusions in the process.
Some commonly TIG welded aircraft parts are the exhaust system, heat exchangers, manifolds, fuel and oxidizer tanks, bleed air ducts, landing gear, motor casings, and various lines of pipes.
The TIG welding process is one of the best arc welding processes you can use to meet stringent aerospace code requirements. For example, AWS D17.1 permits only one in-process correction attempt before the weldment is submitted for acceptance inspection. It can be very challenging to meet such criteria with highly specialized alloys and complex weld geometries. However, advanced TIG welding power sources can help reduce rework, increase inspection pass rates, and amplify your productivity.
Welding thin gauge aluminum and titanium alloys poses a risk of distortion, which is one of the biggest problems when making high-precision welds on thin sheets. This is again where high-endTIG welding power sources come to the rescue. Aerospace fabricators can significantly cut rework and failure rates by using pulsed TIG from reliable power sources that output a waveform precisely as set.
The prime example of a top-of-the-line TIG system is theMiller Dynasty 400. This machine is not just a workhorse of a welder, but one of the most sophisticated TIG machines in the industry. Engineered to provide reliability, accuracy, and unparalleled adjustability, aerospace fabricators often rely on the Dynasty TIG machines.
The Dynasty 400 supports pulsed DC and AC TIG with an extreme pulse range (up to 5000 PPS), giving you maximum heat input control to dramatically reduce distortion and weld oxidation (discoloration) on sensitive alloys. AWS D17.1 asks for the rejection of stainless steel and nickel alloy welds that are black or titanium welds in a range from violet to white. One of the reasons why this happens is excessive heat input, which causes oxide buildup and discoloration. Excessive heat input can also lead to negative metallurgical changes in the HAZ and PMZ of the weld, which is why controlling your welding heat input is critical for safe and sound welds that can pass the inspection.
Besides heat control, Dynasty 400 lets you modify AC frequency, AC balance, individual amperage output of DCEP and DCEN when doing AC TIG, and the AC waveform type. With this many settings, you can fine-tune your welding arc to meet many critical aerospace welding needs. For example, if you weld very thin aluminum sheets, you can use the triangular AC TIG wave coupled with a high PPS pulse to minimize distortion and maximize your chance of success.
The goal is to minimize discontinuities and defects and maximize productivity. However, achieving this goal requires a different approach for various alloys, joint types, and thicknesses, which is where advanced TIG machines like the Dynasty 400 come in. Extreme adjustability ensures you can adapt your TIG arc to almost any application and achieve high productivity.
Orbital TIG Welding In Aerospace
While welders often need to perform manual TIG welding on aircraft parts, orbital TIG is critical for the aerospace industry.Orbital TIG welding is used to join critical pipes and tubes like fuel and hydraulic lines. This is an automated welding process where the orbital head travels around the pipe circumference as it fuses the two pipes together.
An airplane can have thousands of joints in its high-pressure systems. These pipes and tubes are exposed to extreme cyclical mechanical and thermal stresses as the airplane takes off, lands, and maneuvers in the skies. When you are flying with a commercial airliner, for example, hydraulic systems work hard whenever the plane needs to bank to one side, alter its bearing, or change its altitude. The pressure in the hydraulic lines forces the fluids to move the landing gear, flaps, spoilers, pitch control, and other critical maneuvering elements. Whenever there is a loss of pressure in the system due to a weld failure or other reasons, the pilot could lose control of the plane, depending on different factors.
Since aircraft tubes and pipes are so critical for safety, their welds must be as close to perfection as possible, and orbital TIG welding is the best way to achieve this goal.
Welding pipes and tubes manually is a significant challenge due to operator fatigue, minimal clearances, and difficulty achieving code criteria. However, automated orbital welding solves all of these challenges. Operators can weld during their shifts without fatigue being a factor, as they never have to weld in difficult positions. Theorbital weld heads can be quite small, and fuse tubes in the tightest clearances. Most importantly, orbital welding provides exceptional weld quality and accuracy consistently.
MIG Welding In Aerospace
The MIG welding process also plays a significant role in the aerospace industry, especially in automated welding configurations. While TIG offers maximum weld accuracy and purity, MIG is far more productive and can produce similar results when using the right equipment.
Unlike TIG, MIG uses continuous filler metal wire. As a result, operators don’t have to pause the weld to get a new wire. Likewise, MIG is far faster than TIG in manual and automated applications. So, whenever possible, MIG is used instead of TIG to improve productivity and cut costs.
However, MIG welding is subject to the same AWS D17.1 code for aerospace applications. So, it’s critical to useadvanced process welding equipment to produce quality welds and achieve high productivity.
TheLincoln Electric Power Wave S500 is an advanced multi-process welder with high-end MIG welding capabilities. It includes over 65 welding waveforms for optimized performance for various metals, thicknesses, shielding gases, and wire types. It also supports proprietary Lincoln Electric technologies like STT, Hyperfill, low fume pulse, and highly accurate pulsed MIG performance. In addition, it supports the Lincoln Electric CheckPoint Welding Production Monitoring suite, which allows cloud weld data collection and monitoring. This can help you provide necessary data for customer ISO, statistical process control, equipment effectiveness, and other vital information that demonstrates your welding productivity and process control.
Another exceptional machine for MIG welding aerospace parts is the Miller XMT 450. It’s a multi-process welder with outstanding MIG performance. Its pulsed MIG is complemented with Miller’s SharpArc technology, which gives you total control over the arc cone and bead profile. SharpArc can help you achieve code criteria when it comes to bead profile and weld size when used correctly. Likewise, its advanced pulsed MIG mode can help you reduce average heat input and prevent distortion and burn-through on thin metals. And most importantly, applying the pulsed MIG welding process can achieve weld quality similar to TIG when set correctly. This is especially the case when combining the Miller XMT 350/450 with the Miller AlumaFeed Synergic wire feeding system. Using Miller’s Profile Pulse technology, you can achieve TIG-like welds while experiencing the MIG’s productivity gain.
Robotic MIG Welding
While manual MIG provides significant productivity gain over TIG, using a cobot to MIG weld can drastically improve productivity, weld accuracy, and inspection pass rates. When applicable, welding cobots can significantly improve your bottom line and help you overcome skilled labor shortages.
Red-D-Arc BotX™ is a collaborative robot that works alongside your operators. It’s so easy to set up and use that most shops experience its benefits in just a few hours. Your operators can guide the robot’s hand manually and use a highly intuitive smartphone app to program the weld path and arc settings in just a few clicks.
BotX can use Millers XMT 350/450 or OTC P402L/505L MIG power sources and output a highly stable arc with multiple advanced configurations to achieve reliable, high-quality welds with minimal operator involvement. As a result, you can almost completely automate repetitive part welding and have your best welding operators focused on the most exciting and demanding applications, like welding aircraft fuel lines, tanks, landing gear, structural components, and other parts where maximum expertise is required.
Weld Monitoring For Aerospace Applications
Since welding codes and standards in the aerospace industry are so stringent and client expectations are so high, fabricators often use advanced weld monitoring systems to see and record the welding process of critical welds.
Weld monitoring allows a real-time overview of the process and lets the operator pick up defects as they occur. It’s possible to see misalignment of seams, undercuts, porosity, shielding gas coverage inefficiencies, welding tip degradation, and other problems as they occur. This can help improve productivity by preventing the problem at its root instead of waiting for the inspection. This is especially important when making a large batch of parts. Finding out that there was an issue with the welding process after completing tens of parts is an unnecessary waste of resources.
Critical welds can also be recorded to provide quality assurance. Likewise, troubleshooting is much easier if you have a high-definition video of the welding arc and the joint.
Xiris XVC-O Weld Monitoring System is used for open arc applications, like TIG, MIG, Plasma arc, and laser welding in aerospace applications. These systems use sophisticated sensor technology to provide exceptional contrast and clear the image of excessive arc brightness. As a result, you get a clear picture showing how the metal melts and fuses.
Red-D-Arc – Your Trusted Partner For High-End Welding Equipment
Whether you are a contractor for large aerospace brands or running your shop for private aircraft repairs, Red-D-Arc is here for all your MIG and TIG fusion welding needs. Leverage technologies like robotic welding, advanced power sources, heat induction systems, and weld monitoring cameras to deliver exceptional performance and achieve high productivity.
Contact us today, and our experts will help you choose the welding equipment rentals for your shop.
One of the most fundamental parts of arc welding is right there in the name of the arc. Arc welding uses an electric arc to generate the immense, guided energy and heat necessary to melt both the surface of the workpiece and any filler material you’re using for a welding job.
Different kinds of welding use different methods to create that arc. There are three main methods for starting an arc, and each of them has its own pros and cons. Let’s go through each of the three, their benefits and drawbacks, and anything else you need to know about them.
Welding is typically a process of joining two pieces of material using the heat generated by an electric arc and often a filler material to add and strengthen the resulting joint. However, the same basic technique can be used in other ways by adjusting a few parameters. A primary example is plasma cutting, which is largely the same as arc welding but with a controlled jet of gas used to melt and blow away material to cut rather than combine.
A similar adjustment of parameters leads to hardfacing. Some think of hardfacing as a complex and advanced technique that only the most experienced welding operators can pull off. Others just consider it an irritation and not worth the time and effort required to perform it. What is it, though, and how can you use the process? Let’s discuss.
What is Hardfacing and How Does it Work?
Hardfacing is a process where you use the general concept of welding – specifically the deposition of material – to coat the outside of a base metal with a tougher, harder metal. This can make the resulting workpiece more durable, more resistant to abrasion, wear, and damage, and expand its longevity. Hardfacing is performed using specialized electrodes or filler rods but largely uses the same kind of arc welding process to melt those fillers onto the surface of the base material.
This isn’t quite the same as something like adhering a shell to the outside of a workpiece. Since the welding process is used, the surface of the base material is melted enough to combine with the filler material, resulting in a merger of the two. This creates a thick, dense layer between 1 and 10 mm, made of a highly bonded, wear-resistant alloy combining the base and filler metals.
Hardfacing improves the surface strength, ductility, wear resistance, corrosion resistance, and erosion resistance of the original workpiece. It can be performed on cast iron, copper, and nickel alloys, stainless steel, carbon steel, and manganese steel.
One key to successful hardfacing is minimizing heat. While you need enough surface melt to the base material to adhere to the hardfacing filler, you want as little mixing as possible because the base material will soften the added material and reduce the utility of the hardfacing. Therefore, knowing what material you’re hardfacing is critical so you can identify ideal temperatures.
What Are the Benefits of Hardfacing?
Hardfacing is a way to strengthen and extend the working life of metal parts that see a lot of wear, particularly surface wear. By hardfacing a worn part, additional lifespan can be drawn from the base workpiece, extending longevity and reducing the need to replace it; this saves money over the long run.
Hardfacing is commonly used in agricultural and mining situations and is frequently also an option for getting more useful life out of a part while a replacement is on order. In remote locations or for specialized parts that need lead time to be made and shipped, when the difference is between halted operations and continued operations, hardfacing can make the difference.
Overall, hard facing can be used to minimize the downtime spent replacing worn or broken parts, allows you to store fewer replacements on-site if you typically do so, and increases the average lifespan of those parts. In many cases, the lifespan of a working piece can be extended by up to 300% with dedicated hard facing, which can mean overall savings for the company of 25% to 75% in the cost of replacements.
Where is Hardfacing Often Used?
Hardfacing can be used in a wide range of different applications. Since it’s coating the outside of a workpiece, it’s generally used on pieces that have to resist impacts or abrasions over time.
In construction, an excavator’s plow is one common piece that has to endure an immense amount of impact and erosion damage. Heavy use of an excavator can wear it down, reducing the strength of the plot and even the workable dimensions of the machine. Hardfacing the plow strengthens it against this kind of damage.
In agriculture, the manufacture of sugar involves crushing sugarcane in a roller. Despite being a plant – which you might not think of as being able to damage metal parts – the sugarcane plant is quite strong and can give as good as it gets. These rollers can be hard-faced to help resist the damage of continually crushing sugar cane and extend the operating life of the machine.
Another common example from mining is the crusher that breaks up larger chunks of ore-bearing material for processing. There are a wide range of different designs for these machines, but many of them end up using plates of metal and heavy motors to crush rock. Rock, too, resists being crushed and will damage and abrade the crusher over time. Hardfacing the jaws of the crusher will help them resist that force and can be used as a repair to restore functionality to damaged jaws before they need to be fully replaced.
Are There Different Techniques for Hardfacing?
Yes. Hardfacing can be performed in two ways: overlay and build-up. These are roughly equivalent to enhancing existing materials and repairing damaged materials.
Imagine a workpiece with many gouges, scratches, abrasions, dings, scrapes, and other forms of damage from long use. The workpiece is worn and nearing the end of its lifespan. Such a piece can be restored with hard facing using the build-up technique. Build-up hardfacing entails using the welding process to deposit hardfacing material and spending additional time and care on the deeper gouges and abrasions to rebuild the working surface of the workpiece. A layer to smooth and even out the working surface is applied, and any finishing is performed.
Overlay hardfacing can be done on pieces that have been built up already using the previous technique or on brand-new or barely-worn pieces that need additional reinforcement to expand their lifespan. This technique simply uses repeated and iterative passes of hard facing to deposit a layer of material across the entire surface of the workpiece; no special care is necessary for repairs because no repairs are necessary. It’s simply a method of reinforcement.
How is Hardfacing Performed?
The step-by-step process of hard facing is relatively simple and similar to many other welding processes. The primary difference is that it takes place over the whole surface of a typically large workpiece rather than along a single seam or crack in the workpiece.
Step one is to clean the part. Since hard facing is typically used on working machines, these have likely built up grime, dirt, oils, greases, rust, and chemicals, all of which can inhibit the performance of a weld and cause inclusions, weaknesses, and faults in the resulting surface. A thorough cleaning is required to avoid cracking, warping, and damage to the workpiece. This process may even need to be performed on brand-new pieces, particularly if they’ve been painted or coated in rust-resistant chemicals.
Step two is to perform build-up hard facing on any deep gouges, abrasions, cracks, or other damage to the surface of the workpiece. Hardfacing requires that the surface be more or less the shape and form you want the finished piece to be, so any repairs you need to make should be made at this step in the process. This isn’t necessary for new pieces you’re reinforcing with hard facing, as there’s likely no damage to repair.
Step three is to “butter” the part. Buttering is the act of forming a thin buffer layer between the base material and the hardfacing material. It’s most commonly used in cases where the two materials are dissimilar and will have a hard time bonding with one another. By using an intermediary as a buffer layer, you can create more comprehensive bonds and reduce the chances of the final coating cracking or shrinking and causing problems.
The fourth and final step is to perform the actual hard facing. This is where you apply your coats of hardfacing material. This may be spotty and sporadic, or it may be comprehensive and can be anywhere from one to three coats for most situations.
One critical component of the actual hardfacing process is deciding on a hardfacing pattern. While a complete coat of cladding can be used, this is often unnecessary, depending on the purpose of the workpiece. Other patterns include:
Dots. A dot pattern involves using a series of regularly spaced dot-shaped welds to deposit the hardfacing material across the surface. This is typically used on machines that deal with larger rocks and aggregate; smaller material can fill the gaps between the raised dots, while the raised dots become the source of impact and are strengthened against it. Other types of impact are cushioned by the “dead bed” between the dots.
Stringers. Stringers are long, straight beads of welding, typically spaced some distance apart, between a quarter of an inch all the way up to 1.5 inches. This is typically chosen with beads that run parallel to the direction the material flows in use, so it doesn’t “catch” and cause more damage to the hard-faced material.
Waffles. A waffle, criss-cross, or herringbone process is perpendicular beads that leave small square pockets behind. Again, this is usually used for dealing with larger aggregate materials, where smaller materials and sand form a cushioning bed in between.
All of these patterns are ways to save time, energy, and material when hardfacing, so you don’t have to coat the entire working surface of a piece completely.
Hardfacing Frequently Asked Questions
What does successful hardfacing look like? Ironically, hard facing often looks visually like bad welds because it’s an uneven and rough build-up of material on the surface of the workpiece. In a way, it’s almost like more of a “brute force” approach to welding rather than more elegant seams and connections.
What materials can and can’t be hard-faced? Hardfacing is generally done on harder steels, like stainless, manganese, carbon, and alloy steels. It can also be performed on cast iron, nickel-base alloys, and copper-base alloys. Other base materials are often too soft to take hardfacing well or are not used in the kinds of applications where hardfacing is beneficial.
One of the greatest details of hardfacing is that it’s only applicable to high-wear pieces in heavy industry. It’s typically not used in cases where direct wear isn’t responsible for damage. That is, cases where the cause of damage is flexing stress or sheer stress are not going to benefit from hard facing.
What’s the best process for hard facing? Many forms of hard facing are performed using submerged arc welding. Another popular process is flux-core arc welding. However, any welding process can be used for hardfacing, up to and including plasma arc welding, laser welding, and even brazing.
What matters most is the heat control and deposition rates of the process you choose. Some processes have better deposition rates and can hardface a workpiece faster and more effectively. Others need more careful control to avoid overheating the area. At the end of the day, though, what matters most is that you pick a process you’re familiar with and can control well.
What is “wear” in the industry? Most often, wear is caused by abrasion with a material like rock or aggregate or by impact. Sometimes, wear can be defined as metal-to-metal abrasion, heat, or corrosion, but these are less common in the cases where hard facing is most beneficial. Additionally, many different kinds of wear can apply at once; using an excavator to plow can cause both abrasion and impact, for example.
How can you pick the best machine for hardfacing? The best machine for hardfacing is one that can handle long duty cycles with enough power to deposit material quickly and limit the heat-affected zone of the base material. As such, nearly any good welder can handle the process, but it can benefit more from a 220v machine over a 110v machine. Either way, there are many options you can explore to find the welder that best suits your needs. Our welding equipment rentals help you test and try out machines and, if you don’t like them, return and rent different machines.
You should always consider the most typical use scenarios when evaluating plasma cutter rentals. It’s vital to examine your metal-cutting needs to get the most out of your plasma cutting equipment, whether you buy it or rent it.
Plasma cutter power sources, consumables, output power, and cutting speeds vary depending on the cut material and its thickness. So, let’s see how to choose your plasma cutting system without falling short on vital specs and capabilities.
Plasma Cutting Considerations for Thin Metal Sheets
Plasma cutting thin metal sheets creates unique problems like warping and melting. HVAC, auto body shops, custom interior design, and large-scale fabrication are just some applications where fine precision is required when cutting thin metals.
Crude oil and natural gas must be processed before they can be used for energy production. It involves numerous steps in complex facilities that rely on welds to endure severe pressures, chemicals, and temperature swings.
The oil and gas downstream industry borders the limits of what’s possible. Oil refineries, gas processing facilities, and petrochemical plants are some of the most complex structures in our world, with many critical pieces of equipment and destructive processes that can cause devastating damage to personnel and the environment.
These processing facilities comprise numerous pipelines, heat exchangers, furnaces, pressure vessels, structural components, and other elements that must be welded with absolute structural integrity. If the weld fails, the production fails, resulting in huge capital loss and safety issues.
What Is Considered Downstream of Oil and Gas Industry
Refining crude oil and processing natural gas into products ready for consumers is the purpose of the downstream sector of the oil and gas industries. Once the crude energy products are explored and recovered (upstream) and transported to the refineries and processing plants (midstream), they are ready to be refined (downstream).
Depending on the type of processed energy product, processing plants can vary in size, refining methods, and components. But they also share critical equipment like the hydroprocessing reactors needed for hydrotreating or hydrodesulfurization (HDS).
The hydroprocessing reactors remove sulfur from natural gas and crude oil to reduce sulfur dioxide emissions from combustion engines in cars, ships, power plants, and aircraft. In addition, the HDS is a crucial step in refining petroleum because sulfur can destroy catalytic reforming units used to upgrade the octane rating of naphtha streams later in the refinery. So, the downstream sector of the oil and gas industry plays a vital role in our energy’s environmental impact and the produced fuel efficiency.
Welding Challenges In The Oil and Gas Downstream
Oil and gas processing plants have many critical elements and rely on each other to function correctly. But they all rely on weld integrity to keep the refinery running smoothly. However, welding these vital elements is anything but easy. For example, the hydroprocessing reactors we mentioned earlier are exposed to harsh chemicals under high pressures and varying temperatures. They must be made from special steels and welded with alloy filler metal that can withstand such conditions without corrosion.
Depending on processes like hydrotreating, hydrocracking, catalytic cracking, distillation in oil refineries, fractionation, sulfur removal, and separation of water from natural gas in gas processing facilities, various aggressive damage mechanisms can directly or indirectly affect the welds of the element where the process takes place.
Welds and base metals of the pressure vessels, pipes, furnaces, and heat exchangers are threatened by high-temperature hydrogen attack (HTHA), stress rupture, flue gas dew point corrosion, sulfuric acid corrosion, hydrogen diffusion from wet H2S damage, and tens of other damage mechanisms. Preventing weld cracking, corrosion, and hydrogen-related issues, takes a very specialized approach for each element of the processing facility.
For example, HTHA occurs in steels operating at elevated temperatures in hydrogen environments, like those in hydroprocessing reactors. HTHA can cause fissures, cracking and lead to significant loss of steel’s mechanical properties due to loss of carbides and formation of voids. However, certain Cr-Mo steels are not susceptible to HTHA, so the 2.25Cr-1Mo-0.25V steel alloy is commonly used for hydroprocessing reactors. But, welding this alloy is challenging due to weld cracking and re-heat cracking sensitivity and very stringent intermediate and post-weld heat treatment requirements.
Welding For Oil Refineries and Gas Processing Facilities
Crude oil and natural gas must be processed before they can be used for energy production, which involves numerous steps in complex facilities that rely on welds to endure severe pressures, chemicals, and temperature swings. The oil and gas downstream industry borders the limits of what’s possible. Oil refineries, gas processing facilities, and petrochemical plants are some of the most complex structures in our world, with many critical equipment and destructive processes that can cause devastating damage to personnel and the environment.
These processing facilities comprise numerous pipelines, heat exchangers, furnaces, pressure vessels, structural components, and other elements that must be welded with absolute structural integrity. If the weld fails, the production fails, which can result in huge capital loss and safety issues.
What Is Considered Downstream of Oil and Gas Industry
Refining crude oil and processing natural gas into products ready for consumers is the purpose of the downstream sector of the oil and gas industries. Once the crude energy products are explored and recovered (upstream) and transported to the refineries and processing plants (midstream), they are ready to be refined (downstream).
Depending on the type of processed energy product, processing plants can vary in size, refining methods, and components. But they also share many critical equipment like the hydroprocessing reactors needed for hydrotreating or hydrodesulfurization (HDS).
The hydroprocessing reactors remove sulfur from natural gas and crude oil to reduce sulfur dioxide emissions from combustion engines in cars, ships, power plants, and aircraft. In addition, the HDS is a crucial step in refining petroleum because sulfur can destroy catalytic reforming units used to upgrade the octane rating of naphtha streams later in the refinery. So, the downstream sector of the oil and gas industry plays a vital role in our energy’s environmental impact and the produced fuel efficiency.
Welding Challenges In The Oil and Gas Downstream
Oil and gas processing plants have many critical elements and rely on each other to function correctly. But they all rely on weld integrity to keep the refinery running smoothly. However, welding these critical elements is anything but easy. For example, the hydroprocessing reactors we mentioned earlier are exposed to harsh chemicals under high pressures and varying temperatures, so they must be made from special steels and welded with alloy filler metal that can withstand such conditions without corrosion.
Depending on processes like hydrotreating, hydrocracking, catalytic cracking, and distillation in oil refineries, or fractionation, sulfur removal, and separation of water from natural gas in gas processing facilities, various aggressive damage mechanisms can directly or indirectly affect the welds of the element where the process takes place.
Welds and base metals of the pressure vessels, pipes, furnaces, and heat exchangers are threatened by high-temperature hydrogen attack (HTHA), stress rupture, flue gas dew point corrosion, sulfuric acid corrosion, hydrogen diffusion from wet H2S damage, and tens of other damage mechanisms. Preventing weld cracking, corrosion, and hydrogen-related issues, takes a very specialized approach for each element of the processing facility.
For example, HTHA occurs in steels operating at elevated temperatures in hydrogen environments, like those in hydroprocessing reactors. HTHA can cause fissures, cracking, and lead to significant loss of steel’s mechanical properties due to loss of carbides and formation of voids. However, certain Cr-Mo steels are not susceptible to HTHA, so the 2.25Cr-1Mo-0.25V steel alloy is commonly used for hydroprocessing reactors. But, welding this alloy is challenging due to weld cracking, re-heat cracking sensitivity, and very stringent intermediate and post-weld heat treatment requirements.
The Challenges of Welding Critical Equipment
Welding critical equipment of oil refineries, petrochemical plants, and gas processing facilities has a lot of challenges. Many engineering fields come together to solve these issues and push what’s possible in these industries. As the example above shows, solving one problem, like HTHA, can create a more challenging welding operation. Institutes like the American Petroleum Institute make standards and operating practices and continue to push for improved safety and equipment efficiency.
Hot tapping is an additional welding challenge in oil refineries and processing facilities. Hot tapping refers to welding the operational pipeline or equipment without shutting down the process equipment. To perform hot tapping, it’s necessary to meet specific OSHA and API safety codes and practices. Hot tapping is only performed when the refining process cannot be stopped or if the shutdown is impractical.
Welding Processes Employed In the Oil and Gas Downstream
Since the processing equipment is highly diverse downstream of the oil and gas industry, numerous welding processes are employed in the shop and on-site environments.
Fabricating pressure vessels often require submerged arc welding (SAW), while many details like nozzles and fittings are welded using gas tungsten arc welding (GTAW), flux-cored arc welding (FCAW), and shielded metal arc welding (SMAW). In addition, pipes and pressure vessels require internal surface weld overlay with non-corrosive alloys, otherwise known as cladding, performed using automated GTAW cladding equipment.
Heat exchangers can be manufactured on-site or in the fabrication shop. Due to the nature of circumferential tube-to-sheet metal welds requiring maximum accuracy, heat exchangers are welded using the GTAW process.
On-site repairs are often performed using SMAW and GTAW depending on the type of repair, required weld accuracy, and the welded material.
Post-welding heat treatment (PWHT), interpass temperatures, dehydrogenation heat treatment, intermediate stress relieving, and other heat-related processes rely heavily on induction heating equipment to ensure a sound weld. The Miller ProHeat Rolling Inductor is an excellent example of a highly efficient and safe induction heating system for fabricating pipes for oil refineries and petrochemical processing plants.
Benefits of Welding In The Oil and Gas Downstream
Without welding, there would be no oil refineries and gas processing facilities. But welding has certain innate benefits for the whole downstream of the oil and gas industry.
Speed
Any failing element of the oil refinery means a significant bottleneck in production which will cause dramatic capital loss. However, skilled welders can quickly repair leaks and cracks using portable and quick-to-set-up welding equipment. Welding minimizes downtime and helps to quickly get the facility up and running to its maximum capacity. Oil refineries and gas processing facilities operate on relatively tight margins, so streamlined repair and maintenance welding procedures positively affect the bottom line.
Versatility
Welding is a versatile metal joining technology with numerous processes where each can be best suited for specific refinery equipment. The universal nature of welding processes allows the joining of hundreds of metal alloys and all joint configurations in various environments for equipment with highly varied service conditions. No matter the complexity of the task, at least one welding process can be configured to create welds that pass the inspection and meet code criteria.
Efficiency
The efficiency of welding technologies affects the success of any oil refinery or gas processing facility. The cost to build, repair, and maintain pipelines, pressure vessels, furnaces, heat exchangers, and other critical equipment is significant. Automated welding equipment can cut costs and improve the time-to-completion of most equipment fabricated in the workshop, and some that are constructed on-site. Welding positioners, motorized turning rolls, pipe bevelers and cutters, orbital welders, and other automated equipment drastically improve welding efficiency and reduce the cost of the finished product.
Precision And Joint Quality
Weld precision and joint quality are crucial for all critical elements of oil refineries and gas processing facilities, especially pressurized equipment and pipelines. Large vessels operate at extreme pressures containing aggressive chemicals at high temperatures inside.
Therefore, creating precise and strong joints is paramount. Using automated fit-up bed tank rollers, it’s possible to precisely align the pressure vessel joint before welding with the SAW or another welding process using a mechanized longitudinal seam welder. Joint accuracy is essential in many other instances, and welding technologies can solve all of them. Some welding processes, like the GTAW, are inherently more precise, but the process selection comes down to the material, joint type, costs, and operational conditions of the welded element.
Work With The Best Equipment – Rent Or Lease From Red-D-Arc
While welding is one of the cornerstones of the downstream oil and gas industry, its benefits can only be fully harnessed with quality welding equipment. To meet stringent code requirements and pass weld inspection, the welding power sources must possess advanced features and impeccable arc quality. In addition, automated welding equipment needs to be configured for precise operation and be maintained for maximum reliability.
Red-D-Arc has a massive fleet of top-notch welding, cutting, and heating equipment for manual and automated welding.
Contact us today, and let’s discuss your equipment needs, whether you are a contractor maintaining and repairing structures of the downstream oil and gas industry or working on building critical equipment for these facilities.
Airgas, an Air Liquide company, is the nation's leading single-source supplier of gases, welding and safety products. Known locally nationwide, our distribution network serves more than one million customers of all sizes with a broad offering of top-quality products and unmatched expertise.
