A hydraulic press consists of several parts, including mechanical structural components, a hydraulic system, an electrical control system, and auxiliary devices. All these components collectively determine the equipment’s accuracy, stability, and service life.
1. Mechanical Structure Components
1) Machine Body (Frame)
Four-column type / Frame type / Single-arm type
Material: Q355B high-strength steel plate
Function: Bears pressure and ensures the rigidity and stability of the entire machine
2) Slider (Movable Crossbeam)
Connected to the main hydraulic cylinder, performs the pressing action
Key points:
- Parallelism
- Rigidity
- Guiding accuracy
3) Work Table
Used to place molds and workpieces
Optional:
- T-slot
- Lower ejector cylinder / Stretching pad
- Movable work table
4) Guiding Device
Four-column guide bushings / Guide rails
Common materials: Copper-based alloy, wear-resistant composite materials
Function: Ensures the accuracy of the slider’s up and down movement
2. Core Components of the Hydraulic System (Most Critical)
5) Hydraulic Cylinders
Main cylinder (provides primary pressure)
Stretching pad cylinder / Ejection cylinder / Auxiliary cylinder
Key indicators:
- Sealing performance
- Coaxiality
- Resistance to eccentric loading
6) Hydraulic Pumps
- Gear pump
- Piston pump (variable/fixed displacement)
- Servo hydraulic pump (energy-saving type)
👉 Determines pressure stability and energy consumption level
7) Hydraulic Valve Group
- Solenoid directional control valve
- Proportional valve / Servo valve
- Relief valve, pressure reducing valve, throttle valve
👉 Controls direction, speed, pressure, and sequence of operations
8) Oil Tank
Oil storage, heat dissipation, and impurity sedimentation
Configuration:
- Level gauge
- Thermometer
- Breather
9) Piping System
High-pressure oil pipes / Seamless steel pipes
Quick-release couplings / Flanges
Function: Transporting hydraulic oil
3. Electrical and Control System Components
10) PLC Control System
Mainstream brands: Siemens, Mitsubishi, Omron, etc.
Enables automatic, semi-automatic, and manual control
11) Touch Screen (HMI)
- Parameter setting
- Process recipe storage
- Fault alarm display
12) Sensors
- Pressure sensors
- Displacement sensors
- Temperature sensors
👉 Ensuring molding accuracy and safety
13) Electrical Components
- Relays
- Contactors
- Frequency converters / Servo drives
4. Safety and Auxiliary Accessories
14) Safety Protection Devices
- Photoelectric protection (safety light curtain)
- Two-hand operation buttons
- Emergency stop button
15) Cooling System
Air cooling / Water cooler
Controls oil temperature and extends component lifespan
16) Lubrication System
Manual / Automatic lubrication pump
Ensures long-term stable operation of guide rails and guide columns
17) Mold-related Accessories
- Quick mold change device
- Mold heating plate (for compression molding)
- Ejection mechanism
5. Common Wear Parts (Frequently Asked by Customers)
- Hydraulic cylinder seals
- Hydraulic valve spool
- Hydraulic pump
- Pressure sensor
- Hydraulic hoses and fittings
The core components of a hydraulic press are the hydraulic cylinder, hydraulic pump, and control system. Structural components determine stability; the hydraulic system determines accuracy and service life; and the electrical control system determines automation and efficiency. Learn more about hydraulic presses from PDH‘s technical staff. Contact us!
