Seam Welding and Stitch Welding Metal fabricated projects

A steel fabricated product is sometimes as good as the weld that keeps it together. Not only is it important for an engineering designer to determine the proper weld processing to apply, also the steel welding technique to implement. That can be a little trickier. 

Two Welding Techniques: Seams & Stitches

In general, engineers and welders have two welding techniques to choose from on a metal fabrication project; Seam welding and Stitch welding. It is common for many to be confused with the differences in them.

Heat is applied to melt and join metal for both welding techniques.This changes the mechanical properties of the metal and causes expansion and contraction. That is where choosing the proper welding technique to use comes in. Both welds have different advantage properties and are used for different purposes.

Choosing the proper welding methods could mean the difference between a failing joint and a long-lasting weld. Typically, the projects designer will decide if a project calls for a stitch weld or seam weld. The strength required in the welding joint, what the fabricated product will be used for, and other design aspects will be factored into the decision on the weld to be used.

Welding instructions will be added on the fabrication drawing. This tells the welder, among other things, whether to use stitch or seam welding while completing a project.

Stitch Welding

Stitch welding is intermittent. It involves initiating a weld, welding for a part of the joint length, terminating the weld, and then starting along the joint again at a certain distance from the previous weld. This can be done for both corner and flat welds. 

Because large amounts of heat can cause part distortion, Stitch welding (intermittent welding) can be used to limit the amount of heat transferred to a part. High temperature can also negatively impact a material's chemical components and mechanical properties. These negative effects can be limited with stitch welding,

It also means less filler metal is used, which saves money, and the weld is usually completed in less time than if it was continuous. Reducing the weld time speeds up the fabrication process.

Stitch welding does have some disadvantages. When the overall weld length is reduced, this oftentimes comes with a reduction in the strength of the weld joint. Also, the portions of a weld joint that are left unwelded could be in the form of a crevice. This crevice may accumulate foreign material that could increase the corrosion rate of the base material. 

Seam Welding

A seam welding is a continuous weld along a welding joint. This can also be done for both corner and flat welds.This is often seen where pipe or tube is welded. Because of the amount of surface area that is joined by a weld, seam welding is robust and is more durable.

Seam welding produces an extremely durable welding method Since the joint is forged due to the heat and pressure applied. 

Stitch welding is the usually the default option for most applications because it minimizes part distortion and saves a little money, but there are times when seam welding yields a better result. 

It's important for your steel detailing prints to call out which type of weld should be used directly in your drawings when you submit them for an estimate. This will ensure a proper quote for your fabrication or structural steel project.

Welding of Zechin Industries is experienced with multiple types of welding techniques. If you have a fabrication project or need custom fabrication solutions, Contact us for a custom quote today.