Back up ring for Link-Belt LS 518

The 9J437 back up ring acts as a mechanical support component within hydraulic sealing systems. It is positioned to prevent the extrusion of primary seals, such as O-rings, into the clearance gaps between machine components when the system is subjected to high pressure. By providing this support, the ring helps maintain the position and shape of the primary seal under load.

This component is compatible with the Link-Belt LS 518 and Manitowoc LS 518 crane models. It is designed to fit into the seal groove alongside the primary seal to provide uniform support across the sealing interface.

In hydraulic systems, back up rings are used to protect softer sealing elements from being forced into gaps by fluid pressure. This function is necessary in applications where high pressure differentials exist, as it prevents the primary seal from being damaged or failing prematurely. Proper installation of this ring ensures that the seal remains effective in containing hydraulic fluid within the system.