Glossary

A spelter socket (often called a poured socket) is a permanent wire-rope termination where the end of a wire rope is inserted into a socket “basket,” the strands are typically unlaid and broomed inside the socket, and then the socket cavity is poured with a bonding medium—classically molten zinc (“spelter”), and in many modern practices an approved resin/poured compound—which hardens and locks the rope wires in place to transfer load into the socket fitting.

Spelter sockets are commonly supplied as open or closed styles (open sockets typically connect with a clevis/pin arrangement; closed sockets provide an eye connection) and are used where a high-efficiency, highly reliable end connection is required for wire rope assemblies in construction, marine/offshore, mining, cranes, and heavy industrial rigging. When properly fabricated with the correct socket and procedure, poured/spelter socket terminations are widely described as achieving near-100% termination efficiency relative to the rope’s catalog breaking strength (i.e., the termination is intended not to be the weak link).

Because they are safety-critical, poured socket terminations are commonly tied to strict fabrication and verification practices. For example, ASME B30.9 includes requirements that new poured socket slings be proof tested prior to initial use (alongside other sling types such as new swaged socket slings).

AKA: Poured Socket