The method you select for welding pipe will depend on the location where the welding is taking place, materials and pipe size.
For welding steel pipes in the open (e.g. pipe installation in trenches), manual arc welding (SMAW) is most common. This technique used is downhill using cellulosic electrodes (also basic electrodes are used for higher strength steel applications). A root pass and a hot pass are followed by the fill passes. The weld is finalized by the top pass. Welding units optimised for downhill welding are utilised.
Welding Smaller Pipes
For small diameter and short length pipes which are free to rotate, the pipe is rotated while the welding torch is held stationary. The processes used are MIG (GMAW) and TIG (GTAW). In the case of TIG welding a wire feeder is necessary. A process cell is best for this type of welding.
Welding Large Pipes
In applications involving larger pipe sizes, welding is generally carried out using the orbital process. MIG is usually employed, but TIG with automatic feed of the filler wire can also be used. Orbital process using closed head welding units is also utilized for applications where smaller pipes cannot be rotated.
There are a number of advanced methods of depositing pipe welds currently in use. These include precisely controlled short circuit transfer for root pass (Miller – Regulated Metal Deposition), optimized pulsed welding (Miller – Pro-Pulse) and high frequency waveform control (Lincoln – Surface Tension Transfer) in order to speed up and improve the quality of the pipe welds.
Red-D-Arc has a wide range of pipe welding equipment for rent including the following:
- Closed head orbital welding units for small pipe diameter
- Orbital TIG welding system for larger pipe diameters
- Orbital MIG welding system
- Process pipe cell with oscillating open arc welding
- TIG and MIG welding power sources suitable for above
- Cutting and bevelling saws for up to 12.75” (325mm) pipe diameter
Have a look at our entire selection of pipe welding equipment which includes pipe cutters and bevelers.
A Red-D-Arc customer based out of the UK was awarded three large offshore wind farm projects …all commencing simultaneously. This manufacturer was comfortable taking on so many large scale, specialized projects because they have a reliable, knowledgeable, tier 1 supplier capable of meeting all of their welding and weld automation equipment needs! Red-D-Arc was able to quickly accommodate all of the welding equipment requirements for the project, providing more than 150 welders and a variety of weld automation equipment. The equipment consisted of multi-operator welding paks, diesel welders, advanced power sources, wire feeders, submerged arc welding packages, and rotators.
Two Red-D-Arc technicians were assigned to the facility to install, service and maintain the equipment to minimize downtime. The facility allocated a permanent workshop and storage container for back-up equipment which could be used to quickly replace any equipment as necessary. With Red-D-Arc’s support, the customer was able to work on all three projects simultaneously and avoid lost time due to equipment breakdowns.
By guest Blogger Katarzyna K.
Katarzyna has an Msc in Materials Science and has worked in the oil and gas industry in jobs related to hydraulics, welding and the retrofitting of oil rigs.
Stainless steel is used extensively in the petrochemical industry due to its high resistance to severe conditions. When welding inox steels, the smallest details matter and have an impact on weld quality. The following are some tips for stainless steel pipe welding based on my oil rig repair experience:
During an oil rig repair project that involved 2205 duplex stainless steel pipe TIG welding, we could not achieve the required weld properties. Despite using the recommended filler metal with higher nickel content, compared to the base metal, and controlling the interpass temperature, the weld tensile strength was still too low. In order to reach the required weld quality we dug deeper and found a solution – (more…)
Red-D-Arc recently supplied a variety of equipment to a UAE based company that is fabricating pile piping and jackets for the largest offshore wind farm project in the world. The company had to meet a strict time line of only 6 months, and would require a massive amount of welding and weld automation equipment immediately. Through consultation with Red-D-Arc, the customer determined that renting the majority of the equipment would be the most economical option. Red-D-Arc was able to fulfil the customers equipment needs immediately thanks to our vast and diverse fleet of equipment.
This massive order involved equipment and support from Red-D-Arc North America, Red-D-Arc UK and Red-D-Arc Middle East. The order consisted of a variety of welding and weld automation equipment including:
• 23 column and booms with single and tandem submerged arc welders
• 20 submerged arc tractors
• 200 rotators
• 167 jack-up rotators
• 400 CC/CV inverter welders
• 200 FCAW wirefeeders
• 10 Induction Heating Systems
By renting the majority of the equipment the fabrication company avoided the need to invest heavily in specialized equipment and ensured they would meet their deadline. Red-D-Arc works with customers to address their unique challenges and develops specialized solutions. Learn more about customized turnkey packages here.
Red-D-Arc carries an extensive inventory of welding equipment designed specifically for pipe welding professionals. The latest pipe welding equipment can increase productivity and produce the highest quality welds. We have an extensive fleet of innovative solutions like the Miller PipeWorx Welding System, Red-D-Arc Oscillating Pipe Welder, Bug-O Systems, Orbital Welding Systems from Lincoln and Axxair, and pipe end prep equipment from H&M and E.H. Wachs.
Check out the new Pipe Welding section of the reddarc.com website to learn more.