Back-up ring for Link-Belt HC238H

The back-up ring, part number 3A20484, serves as a support component within the hydraulic sealing systems of heavy machinery. Its primary function is to provide structural reinforcement to a primary seal, such as an O-ring, preventing the seal from extruding or deforming when subjected to high fluid pressure. By maintaining the position and shape of the primary seal, this component helps preserve the integrity of the hydraulic circuit.

This component is compatible with the Link-Belt HC238H crawler crane. The part is manufactured to meet the specific requirements for fitment within the hydraulic assemblies of this machine. Proper installation of the back-up ring ensures that the sealing system functions correctly within the cylinders, valves, and pumps of the crane.

In hydraulic systems, back-up rings are positioned in the seal groove alongside the primary sealing element. They act as a mechanical barrier that fills the clearance gap between mating surfaces, which is where extrusion typically occurs under pressure. By filling this gap, the back-up ring allows the primary seal to maintain its sealing function without being forced into the clearance space, thereby preventing premature failure and fluid leakage.