Hydraulic ram for underground working - has extension eye on piston rod having galvanised surface, and sliding liner with grooves for compression and wiper rings

摘要

A hydraulic ram for pushing or pulling for underground working has an extension eye (18) on the piston rod (17) with a galvanised surface (19). At one end of the cylinder (2) an interchangeable sliding liner (9) is fitted and this has inner grooves (24,32) to accommodate compression and wiper rings (25,22). The wiper ring (22) is of polyester with a compression lip (23). The liner (9) of galvanised bronzed tempered steel and the hardened surface (19) grips around the extension eye (18) of micro alloy steel in one piece with the forged piston rod (17). USE/ADVANTAGE - The improved ram gives longer life and greater efficiency.