Welding is an important process used in almost all industries today. With over 120,000 welders in the US alone, the number of welders and welding techniques used in all industries is huge.
From energy and shipping to automotive, welding is essential for many applications, particularly in the oil and gas sector. When it comes to welding pipelines, what type of welding is best? In this article, we’ll discuss the different types of welding used for pipelines and the specific weld process used.
With over 1 million miles of pipelines spread throughout the US and carrying over 5 billion barrels of oil and natural gas each year, these pipelines require the best welds to ensure safe operations.
What type of welding is used for pipelines?Welding is a critical aspect of the construction of pipelines. It is a process that binds two pieces of metal together.
In order to meet the stringent requirements of pipeline construction, several types of welding processes are employed. The most commonly used welding processes for pipelines are shielded metal arc welding (SMAW), Gas Tungsten Arc Welding (GTAW), Submerged Arc Welding (SAW), Flux Cored Arc Welding (FCAW), and Electroslag Welding (ESW).
Shielded Metal Arc Welding (SMAW)Shielded metal arc welding, also known as MMA or manual metal arc welding, is a process in which an electric arc is struck between a consumable electrode and the workpiece. A flux-coated metal arc electrode is used in SMAW and the heat generated melts both the electrode and the metals being welded, which flow together to form a weld. This welding process is widely used in pipeline construction due to its low cost, ease of use, and portability.
Gas Tungsten Arc Welding (GTAW)Gas tungsten arc welding is an arc welding process in which a non-consumable tungsten electrode is used to create the weld. A shielding gas and filler metal are fed through the welding torch in order to protect the weld and facilitate a strong weld joint.
As GTAW is a precise and highly-controllable welding process, it is often the preferred choice for welding pipelines for both quality control and meeting any stringent codes and standards.
Submerged Arc Welding (SAW)Submerged arc welding (SAW) is a process that uses an electric arc between a continuously-fed filler metal electrode and the workpiece.
In this process, the arc is protected and “submerged” beneath a blanket of granular flux made up of powdered or granulated flux. This shields the weld pool and creates a weld that is free from slag and other impurities. Due to its high process speed and quality, SAW is very popular for pipelines of greater thickness.