Weld Studs
Weld studs are the key to Embed plates. They are sometimes called Nelson studs, but that name is a trademark of one of the manufacturers of weld studs. They are typically made of ASTM 29, Low Carbon Mild Steel, though can found in many specifications including stainless steel.
Weld Studs come in a variety of sizes. They are measured and specified as shown in the diagram on the left. A stud is primarily defined by the Length (L) and the Diameter(D). The Head dimensions (H & A) are typically dictated by the Length and Diameter of the stud but are occasionally be specified.
Diameters of weld studs
Length of Weld Studs
For structural applications, Studs are typically between 1/4" and 3/4" in Diameter and upwards of 4" -12" long. When studs are welded to a plate they become slightly shorter. This is referred to as "burn off" and can range from 1/8" to 3/8" depending on the diameter of the stud.
Dimensions of a Weld Stud
Anatomy of a Weld Stud
Stud Head
Surrounded by concrete, it provides the necessary resistance to prevent the stud from bulling out of the concrete.
Stud Body
Transfers the load from the plate to the stucture
Flux Tip
On the bottom of the weld stud, you can see a small ball of aluminum flux. This vaporizes almost instantly when the arc is fired and consumes the oxygen at the weld site.
Stud welding uses ceramic ferrule that covers the base of the stud as it is welded which concentrates the heat generated, prevents oxidation, shields the welding arc, and retains the molten metal in the weld zone.