The Z2S10-20B Type Modular Hydraulic Operated Check Valve is a pilot-operated sandwich plate check valve designed to provide reliable load holding and leak-free shut-off in hydraulic systems. The valve allows free flow in one direction while blocking reverse flow until pilot pressure is applied. It is widely used in hydraulic cylinders, lifting equipment, machine tools, and industrial automation systems where secure actuator positioning is required.

Designed according to ISO 4401-05 (NG10/CETOP 5) standards, the Z2S10-20B can be installed directly between directional control valves and subplates, simplifying hydraulic circuit design and reducing installation space.

Working Principle

The Z2S10-20B incorporates one or two pilot-operated check valve elements that control oil flow through ports A and B.

Free Flow Direction

Hydraulic oil flows freely:

• A1 → A2
• B1 → B2

The poppet automatically opens when flow is in the permitted direction.

Blocking Direction

When reverse flow occurs:

• The check poppet closes tightly against the valve seat.
• Hydraulic oil is blocked.
• The actuator remains locked in position.

Pilot Release Function

When pilot pressure is applied from the opposite port:

• The pilot piston pushes the poppet away from its seat.
• Reverse flow becomes possible.
• The hydraulic cylinder or actuator can move under controlled conditions.

This function effectively prevents unintended load movement while allowing smooth actuator operation when required.

Product Features

• Pilot-operated check valve design
• Sandwich plate modular construction
• ISO 4401-05 / CETOP 5 mounting standard
• Leak-free load holding function
• Free flow in one direction
• Pilot-controlled release in reverse direction
• Compact and space-saving design
• Low pressure loss
• High reliability and long service life
• Easy installation and maintenance