Hydraulic cylinder repair bench for mining dump trucks

The bench is intended for hydraulic repair sections that rebuild body hoist cylinders, hydro-pneumatic suspension cylinders and steering cylinders of mining dump trucks. The complete cycle is carried out at one workstation: clamping the cylinder, unscrewing the gland nut or end cap, withdrawing the rod with the piston, replacing the seals, reassembly and pressure testing of the assembled cylinder.

The base of the bench is a welded bed with guideways along which a V-block carriage and a thrust gantry travel. The cylinder is laid on height-adjustable V-blocks and clamped by hydraulic clamps. A hydraulic torque wrench head with a set of interchangeable sockets unscrews and tightens the end caps with torque control, while a hydraulic rod gripper with a stroke over the full length of the guideways withdraws the rod and piston from the barrel and inserts them back without misalignment.

The test circuit consists of a power unit, a directional valve and pressure transducers on both chambers. After assembly the cylinder is bled, held at the proof pressure and checked for external leakage and internal leakage past the piston, with the test report recorded automatically. On request the bench is supplemented with a barrel honing attachment, a turntable for mounting the cylinder vertically, a fluid filtration station and a nitrogen charging station for suspension cylinders.