This is a field-welded moment connection. Full-penetration welds are required at the beam flanges. The web plate is shop-welded to the column flange and is there to locate the correct position of the beam and hold it until it can be welded. Backing bars are usually required beneath the full-pen welds and are sometimes left in place. Access holes are burned into the beam web to facilitate field welding.

A weld around the shear tab to the beam web can be used to increase shear capacity.