Meeting Energy Demands with a New Welding Process

With pipeline projects worldwide looking for ways to build longer pipelines, faster and more efficiently, some contractors are converting from the stick welding process to a self-shielded flux-cored wire process to weld on high-strength pipeline projects. Here are three main reasons for this transition.

It’s not surprising with today’s energy demands that contractors who weld on pipeline projects worldwide are looking for ways to build longer pipelines, faster and more efficiently. One of the ways that they are achieving this goal is by using high-strength materials, including Grade X80 steel.

High-strength materials are thinner and therefore weigh less, which reduces the cost for shipping them to the remote areas where today’s pipelines are often found. These materials are also quicker to weld, since they require fewer passes, and they allow contractors to build pipelines with greater carrying capacity and higher operating pressures.

To add to those efficiencies and cost savings, some companies are converting from the stick welding process to a self-shielded flux-cored wire process to weld on high-strength pipeline projects. There are three main reasons for this transition.

First, the self-shielded flux-cored wires that filler-metal manufacturers have designed for pipeline applications provide high strength properties and also lower hydrogen content – typically less than 8 ml per 100 g of weldment. Low hydrogen is a critical feature considering that high-strength materials also possess high yield strength and a relatively low carbon base, making them prone to hydrogen-induced cracking.

Secondly, the self-shielded flux-cored wire process allows for relatively easy operator training. When welding high-strength pipe, variables such as pre-heat and interpass temperatures, along with the overall welding parameters (amperage, voltage, etc.), must be carefully monitored. Those features alone make welding this material more difficult. Having a welding process that is easy to use minimizes any additional variables involved with training.

Just as importantly, the self-shielded flux-cored welding process is significantly faster than stick welding. It can help contractors complete weld passes in less time and finish pipeline projects sooner. As in other welding applications, filler metals for high-strength pipe need to meet the mechanical and chemical property requirements of the material. They also need to provide the appropriate ductility to help prevent cracking and to compensate for the extreme temperatures these pipelines will encounter.