By definition, pipe welding and pipeline welding are distinct procedures. Pipe welding is used to create large pipe constructions inside oil refineries and chemical plants. Meanwhile, pipeline welding focuses on developing a uniform and nationwide pipeline network that runs beneath roads and buildings.
What is Pipeline Welding?
Pipeline welding, also known as girth welding, is a fabrication procedure that assembles pipes and forms a network. Pipeline welding necessitates a unique set of skills and knowledge, as welders must be able to weld in a variety of positions and settings, frequently operating in isolated places and adverse weather conditions.
Common Types of Welding Used in Pipelines
The following welding methods are typically used in pipelines:
Shielded Metal Arc Welding (SMAW)
Manual Metal Arc (MMA) or Shielded Metal Arc Welding (SMAW) is one of the most used kinds of pipeline welding. It is also known as stovepipe welding since it does not require shielding gas or flux, making it more adaptable and portable with a slower travel speed. An electric arc generates heat, which melts the electrodes used to solder the pipelines.
Flux-Cored Arc Welding (FCAW)
Unlike GMAW, Flux-Cored Arc Welding (FCAW) use semi-automatic devices to easily pierce metals without the requirement for external shielding gas. FCAW has lower deposition rates, but it is suited for windy situations and outdoor applications.
Submerged Arc Welding (SAW)
In semi-automatic Submerged Arc Welding (SAW), an electric arc is formed between the workpiece and the constantly fed electrode. Tracing is more difficult because the arc is not visible. On the contrary, it provides perfect surfaces as compared to other pipeline welding techniques.
Each technique has advantages and disadvantages, and the choice will be determined by the pipeline’s specific requirements.
How to Begin Pipeline Welding?
Before starting the technique, be sure to prepare fundamental pipeline welding equipment such as:
Power source
Welding guns
Connector cables
Shielding gas equipment
Wire feeder
The following are the actions to take before welding your pipelines.
Prepare joint-butt welds in accordance with the API 1104 standard criteria.
Clean the pipeline ends to remove any rust, paint, varnish, or excess oil.
Weld in the root passes after validating the preheat requirements and other criteria.
Examine the welds to guarantee that they are of the greatest quality and that the pipeline is secure and dependable. Any problems or flaws in the welds must be detected and fixed before the pipeline can be put into service.
The pipeline can be tested using a variety of techniques, including hydrostatic and pneumatic testing. Hydrostatic or pneumatic testing includes filling a pipeline with water, air, or gas and pressurizing it to a predefined level to detect leaks or faults.
Perform routine inspections of welding components and repairs as needed.
