Limitations on Plug and Slot Weld Dimensions

The short answer is the larger the plug the easier it is to weld If you are not given specifications then I would use a 1 diameter hole through the 12 sheet

Slot weld is also shown in the figure above It is quite similar to the plug weld, except that the hole is not circular, it is an elongated hole

slot 777 big win This document defines plug and slot welds and discusses how they are represented in welding symbols Plug welds use a round hole while slot

slot jackpots The design stress on a plug or slot weld will be same as that in fillet weld and is specified in clause 1 of IS800:2007 Page 40 PROBLEM: An ISMC