An electric resistance welded (ERW) pipe is one of the most versatile tools in the industry. However, ERW pipes are only one of the numerous types of pipe available. It is important to know the differences between each type of pipe so that the right pipe can be chosen.
Rolled and welded pipe is made from sections of steel plate, rolled into cans. The seam of the can is welded and then individual cans are welded together to make the finished pipe. Rolled and welded pipe can be made in diameters of up to 16 feet and over 2.0 inches in thickness.
Spiralweld pipe, like ERW pipe, is also manufactured from steel coil. The difference is the coil is wound at an angle, so the weld runs around the outside of the pipe in the shape of a helix. This allows for a lot more variation in diameter and thickness than ERW pipe. Spiralweld pipe is most commonly used for pipe diameters between 24 in. and 120 in. and for thicknesses of 1.0 in. or less.
In contrast, an ERW pipe is made by rolling metal and then heating the two edges with electricity so they form a weld down its length. This forms a “seam,” differentiating it from a seamless pipe.
A few advantages to note with ERW pipe:
There are no fusion metals used during the manufacturing process. This means that the pipe is extremely strong and durable.
The weld seam cannot be seen or felt. This is a major difference when looking at the double submerged arc welding process, which creates an obvious welded bead that might need to be eliminated.
With the advances in high-frequency electric currents for welding, the process is far easier and safer.
