Hydraulic Components

Parts of the hydraulic system

Point at a number or a part of the drawing.

1. 1Oil tank

   Holds the hydraulic oil. Returning oil settles here and sheds heat and air before the pump draws it again.

   Filters & Cooling (3)

2. 2Suction filter

   Strainer on the pump’s suction line inside the tank. It keeps dirt and metal particles out of the pump.

   Filters & Cooling (3)

3. 3Electric motor

   Drives the pump. Newer machines use a servo motor that only runs as fast as the cycle needs, which saves energy.

   Servo Motors & Drives (1)

4. 4Coupling and bell housing

   The bell housing bolts the pump to the motor and keeps the shafts aligned. The flexible coupling inside carries the torque.

   Pump Coupling & Bell Housing

5. 5Hydraulic pump

   Turns the motor’s rotation into oil flow. Fixed-speed machines mostly use vane or piston pumps; servo-hydraulic machines often use internal gear pumps.

   Hydraulic Vane PumpHydraulic Piston PumpGear Pump (Sumitomo QT32)

6. 6Pressure gauge

   Shows the system pressure, so the operator can check the settings and spot a pressure loss early.

   Hydraulic Pressure Gauge

7. 7Valve manifold

   The valve block that sends oil to each movement. Solenoid valves on top and cartridge valves inside switch clamping, injection, ejection and nozzle movements.

   Control Valves (6)

8. 8Relief valve

   Opens when the pressure goes above its setting and sends the oil back to the tank, protecting the pump, hoses and cylinders.

   Relief Valve / Safety Valve

9. 9Hydraulic cylinder

   Turns oil pressure into straight-line force: for clamping the mold, injecting, ejecting and moving the injection unit.

   Clamping Components (2)

10. 10Accumulator

    Stores oil under nitrogen pressure and releases it in a burst for fast injection, more flow than the pump alone delivers.

    Hydraulic Accumulator

11. 11Oil cooler

    Water-cooled heat exchanger on the return line. It keeps the oil from overheating, which would thin it and wear the seals and pumps.

    Filters & Cooling (3)