Welding is a critical front-end step in the construction of pipelines. According to the latest statistics, about 996% of all gas pipelines in the United States are welded.
In fact, 300,000 miles of new gas pipelines were welded between 2011 and 2018 alone! It’s no surprise then that there is an extensive number of welding processes and techniques used to construct pipelines.
So, what type of welding is used for pipelines? Let’s find out!
What Type of Welding is Used for Pipelines?
Welding is a process often used to join metals together, such as steel and aluminum. When applied correctly, this technique lets construction workers and engineers join structures in a safe and reliable manner.But, many different types of welding exist and each one is used for different tasks. When it comes to pipelines, for instance, specific welding processes must be used to form strong and durable joints between the pipes.
Shielded Metal Arc Welding (SMAW)
The most widely used form of welding for pipelines is known as shielded metal arc welding (SMAW). It is used to connect curved and straight pipes and often requires manual welding.To use this process, welders cut a shaped groove into the pipes using a cutting torch, thus creating a shallow groove where the welding will occur. This technique is known for producing a relatively strong but aesthetically pleasing weld. It is often used for welding pipes that have been made from thick metal.
Gas Tungsten Arc Welding (GTAW)
Also known as tungsten inert gas welding (TIG welding), gas tungsten arc welding (GTAW) is another technique used for pipelines. This complex method allows welders to use a non-consumable tungsten electrode to make a highly precise and deep weld. Because of its complexity, this technique requires a skilled and experienced welder to perform.It is often used for welding smaller and thinner pipes.
Submerged Arc Welding (SAW)
Submerged arc welding (SAW) is often used to join multiple pipes together, as it only requires short welds.This process uses a power supply and feeder, which allows the welder to complete the welding in a safe, consistent and repeatable manner. As the welding is done below a cushion of inert gas and flux, there is a reduced risk of oxidation or porosity occurring. Because of this, welders can create a strong and long-lasting weld. This technique is also commonly used for welding heavy and thick pipes.