How is Nugget Dia calculated in spot welding?

One general criterion of resistance spot-welding is that the weld shall have a nugget diameter of 5*t1/2, “t” being the thickness of the steel sheet. Thus, a spot weld made in two sheets, each 1 mm in thickness, would generate a nugget 5 mm in diameter according to the 5*t½-rule.

What is the typical size of a spot weld nugget?

According to the standard, AWS C1. 4M/C1. 4:2009, the diameter of the weld nugget for low carbon steel sheet with a thickness of 1 mm has to be between 3.1 and 4.4 mm. As a result, if the nugget diameter is within the range, the welding strength will be assured.

What should the Nugget diameter be for spot welding?

general criterion of resistance spot-welding is that the weld shall have a nugget diameter of 5*t1/2, “t” being the thickness of the steel sheet. Thus, a spot weld made in two sheets, each 1 mm in thickness,

How is the diameter of a spot weld determined?

Diameter of the electrode contact surface. One general criterion of resistance spot-welding is that the weld shall have a nugget diameter of 5*t1/2, t being the thickness of the steel sheet. Thus, a spot weld made in two sheets, each 1 mm in thickness, would generate a nugget 5 mm in diameter according to the 5*t -rule.

How big of an electrode do you need for spot welding?

Diameter of the electrode contact surface should be slightly larger than the nugget diameter. For example, spot welding two sheets of 1 mm thickness would require an electrode with a contact diameter of 6 mm.

How can you determine the thickness of a nugget?

It is further demonstrated that it is possible to determine not only the lateral dimension (diameter) of the nugget but also its approximate thickness. The latter is obtained by analyzing the effective ultrasound attenuation caused by the interaction with the modified grain structure inside the nugget.