Servo Hydraulic Press Maintenance: Oil, Temperature and Pressure Settings

A servo hydraulic press drives the main pump with a servo motor and uses fewer control valves to control the ram. It saves energy, runs quietly with little heat, and offers high automation, precision and easy maintenance; it suits stamping, die forging, press fitting and straightening. Correct use and regular maintenance extend service life and keep production safe.

Hydraulic oil

• Oil quality, cleanliness and viscosity largely determine the life of pumps, valves and cylinders; filter the oil strictly and fit an oil filter in the system.
• Change the oil once a year; the first change within three months.

Oil level and temperature

Keep the tank level high enough for circulation and cooling, and keep tank and lines clean for heat dissipation. An oil temperature of 30–55 °C is ideal.

Routine care

• Lubricate the ram regularly, keep exposed column surfaces clean and oil them before each shift.
• Keep the tank area clean to keep dust and water out of the oil.
• Calibrate the pressure gauge every six months.
• Replace components that reach the end of their service life.
• Before long shutdowns, clean machined surfaces and apply rust-preventive oil.

Pressure setting and eccentric load

System pressure is set with the relief valve and should not exceed the rated design pressure, or the pump may fail, valves may stick or the motor may burn out. The original article's example: at a nominal 500 t, the maximum allowed eccentricity of a concentrated load is 40 mm; more can score the columns.

Servo equipment: AS207 CNC servo press-fit machine; four-column presses in hydraulic presses.