What Is a Hydraulic Cylinder? Parts, Types and Sizing

A hydraulic cylinder is an actuator that turns the power of pressurised oil into straight-line motion. Oil from the pump pushes a piston inside the barrel; the piston rod then lifts, pushes or pulls the load. Hydraulic cylinders are found in construction machinery, tipper trucks, presses, agricultural equipment and almost every hydraulic system.

How Does a Hydraulic Cylinder Work?

Oil enters through one port and pushes the piston. The piston and rod move while oil on the other side returns to the tank. A directional control valve switches the ports to reverse the motion. Force depends on pressure and piston area; speed depends on pump flow.

Main Parts

Types of Hydraulic Cylinders

• Single acting: pressure in one direction; returns by load or spring. Tippers, lifting.
• Double acting: pressure in both directions for controlled push and pull. Machinery, presses.
• Telescopic: nested stages for a long stroke from a short body. Tipper trucks and trailers. (Telescopic tipping cylinder guide)
• Welded: end caps welded to the barrel; compact and robust. Mobile and heavy-duty hydraulics.
• Tie-rod: end caps held by rods; easy to service. Stationary industrial machines.
• Plunger (ram): no piston, the rod itself takes the pressure. Short-stroke, high-force applications.

Force Calculation

F = Pressure × Area, Area = π × D² ÷ 4 (1 bar = 10 N/cm²)

Example: Ø100 mm bore, Ø50 mm rod, 200 bar

• Push force: 78.5 cm² → ≈ 157 kN (≈ 16 t)
• Pull force: 58.9 cm² annulus → ≈ 118 kN (≈ 12 t)
• Speed: at 40 l/min the rod extends at about 5 m/min

Always check force in both directions and allow a 20–30% safety margin.

6 Criteria for Choosing a Cylinder

1. Load and required push/pull force
2. Working pressure and pump capacity
3. Stroke and closed length
4. Rod diameter (buckling on long strokes)
5. Mounting type
6. Operating environment: dust, mud, salt, temperature

How to Choose a Hydraulic Cylinder Manufacturer

• Welding certification such as ISO 3834-2 for welded cylinders
• Quality management: ISO 9001, CE conformity
• 100% pressure and leak testing
• Build-to-print capability for OEM projects
• Spare parts and seal kits for the long term
• System know-how: a supplier that also makes pumps, valves and PTOs avoids compatibility issues

Hypo Hydraulic: Hydraulic Cylinder Manufacturer in Turkey

Özceylanlar (Hypo Hydraulic) was founded in 1974 and has manufactured hydraulics since 1985. Our Konya plant (20,000 m² indoor, 30,000 m² outdoor) produces around 20,000 hydraulic cylinders, 25,000 pumps and 20,000 circuit components a year. About 90% is exported.

• Front end and underbody telescopic cylinders, custom hydraulic cylinders
• RINA ISO 3834-2 welding, ISO 9001, CE and TS 11552
• R&D supported by TÜBİTAK
• Cylinders, pumps, valves, PTOs and drive shafts under one roof
• OEM and private-label production for trailer manufacturers, body builders and distributors