End return in welding

End return plays a significant role in welding. End returns, also known as boxing, are when we continue the fillet weld around the corner of a member. This  extension of the primary weld provide more resistance to ensure the perfect functionality of the connection is seismic loading. According to several codes use of end returns may be mandatory in some cases.  AISC has provided some guidelines and requirements to decide if the end returns are necessary or not. The necessity of end returns depends on several factors such as type of loading and weld.

In this picture, you can see a beam-column connection that is supported by end return welding.