Why does the hydraulic universal testing machine not meet the rated load

Purchased backHydraulic universal testing machineThere is no guarantee that there will be no problems. During the test, sometimes the rated load cannot be reached. It may be caused by the following reasons: 1. The system has serious oil leakage, and the screw joint should be checked 2. The oil viscosity is low, and the oil viscosity must be adjusted 3. The belt driving the hydraulic pump slips and loosens due to oil stains and aging. Tighten the belt or replace the belt 4. There is dirt in the oil return valve, which makes the oil return valve core and valve port not seal enough, and there is oil leakage during loading. The oil return valve should be cleaned.

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