plug or slot weld

A plug weld joins the surface of a piece of material to another piece through a hole. The hole can be partially or completely filled with the weld material.

It's a slot weld, so the correct symbol would be a plug weld symbol with .22 on the left and 1.78 on the right. You could also include pitch distance between ...

In the case of a plug or slot weld, a dimension placed within the weld symbol would indicate?

Plug and Slot Welding Symbols Indicating Location and Dimensions of the Weld – fig. 3-11.