| hydraulicmarket |
| Iran |
| 021-55130771 |
The CAT12G G120 grader hydraulic pump is a radial piston variable displacement pump with an operating pressure typically between 280 and 320 bar. The pump consists of a rotor, pistons, control valves, and pressure relief components, accurately regulating oil flow within ±5%. Under normal operation, the pump flow ranges from 140 to 180 liters per minute, and oil temperature should not exceed 90°C. Repairs require specialized hydraulic tools and flow/pressure calibration equipment to maintain the manufacturer’s technical specifications.
During the repair process, the pump is removed from the grader, and all components are inspected for wear, scoring, and corrosion. Pistons, rings, and seals are replaced with OEM-standard parts to reduce internal leakage below 2%. The shaft and rotor undergo vibration and balance testing to minimize noise and vibration. Control and pressure valves are tested with precise gauges to ensure smooth, stable flow.
After reassembly, the pump is tested under real pressure and flow conditions. Flow measurements at 75–85°C must stay within ±5 bar of the factory specification. Proper repair extends service life up to 8,000 hours and reduces oil consumption and hydraulic system wear. Routine maintenance every 500 operating hours, including pressur
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| hydraulicmarket | 021-55130771 |
| hydraulicmarket |
| Iran |
| 021-55130771 |
The Vickers PVH131 hydraulic pump used in the Caterpillar 140G grader is an axial piston variable displacement pump designed for operating pressures up to 300 bar. The pump flow ranges between 131 and 145 cc per revolution, providing hydraulic output with ±5% accuracy. Its housing is made from high-strength steel, and pistons, swash plate, and valves are precision-machined to ensure internal leakage below 2%. The recommended operating temperature range is -20 to 90°C, and ISO VG46 hydraulic oil is advised for optimal performance.
Common failures in PVH131 pumps arise from piston wear, cylinder block scoring, swash plate degradation, or valve clogging. Contaminated fluid or delayed oil replacement can reduce flow, increase internal pressure, and damage rings and O-rings. Shaft or bearing failure is another frequent cause of reduced performance and severe vibration in the 140G grader hydraulic system.
During specialized repair, the pump is fully disassembled, and all components are inspected for wear, corrosion, or damage. Damaged parts are replaced with OEM components, and the shaft and rotor are dynamically balanced. Pressure and flow control valves are recalibrated, and the pump is tested under simulated load conditions. Flow, pressure, and temperature measurements confi
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| hydraulicmarket | 021-55130771 |
