Rexroth Z2S Series Check Valve | Z2S10-1-2X Z2S6-2-4X Z2S32 | Pilot Operated Check Valve

The Z2S Series sandwich plate pilot-operated check valves from Chengyuan Hydraulic are high-performance locking components fully compatible with Rexroth industrial standards. Designed as sandwich plates, these valves are mounted directly between the directional valve and the subplate, enabling leakage-free locking of ports A and B without additional piping. For core models like Z2S10-1-2X and Z2S6-2-4X, we utilize high-hardness, wear-resistant valve seats. Every valve undergoes 100% simulated internal leakage testing to ensure zero-leakage performance at 315 bar, guaranteeing 100% original-place interchangeability.

Technical Specifications :

• Nominal Sizes: NG6 (Z2S6), NG10 (Z2S10), NG16, NG22, NG32 (Z2S32)

• Max Operating Pressure: 315 bar (31.5 MPa)

• Max Flow Rate: 60 L/min (NG6) to 450 L/min (NG32)

• Cracking Pressure: 1.5 bar / 3.0 bar / 7.5 bar (spring options)

• Pilot Ratio: 1:3 to 1:6 (depending on size)

• Locking Configuration: Dual A&B (Standard), -A (Port A only), -B (Port B only)

• Seal Material: N (Nitrile) / V (Viton/FKM)

• Mounting Interface: Compliant with ISO 4401 / CETOP standards

Key Technical Advantages:

• Zero-Leakage Poppet Design: The heart of the Z2S series is a poppet-style metal-to-metal seal. The spool is high-frequency quenched and precision-ground to fit the seat perfectly. This structure is far superior to spool valves for applications requiring long-term position holding (pressure retention).

• Optimized Pilot Opening: The pilot piston stroke is dynamically optimized to ensure smooth, shock-free opening. Even under high backpressure in ports A or B, the precise area ratio allows the pilot to lift the poppet effortlessly, ensuring smooth return flow.

• High-Precision Surface Grinding: The valve bodies are cast from premium materials, with mounting surfaces ground to a flatness tolerance of 0.01mm. This ensures uniform O-ring compression in multi-valve stacks, eliminating interlayer leakage caused by uneven surfaces.

• 100% Static Pressure Retention Test: Chengyuan subjects every Z2S valve to a static high-pressure test exceeding 10 minutes. We monitor micro-displacement at ports A and B to ensure actuators do not experience “drifting” under heavy loads.

Application Areas:

• Hydraulic Lifting Platforms: Prevents platforms from slowly descending due to directional valve leakage.

• Injection Molding Clamping: Ensures consistent clamping pressure throughout the injection cycle.

• Mobile Machinery: Hydraulic locking for crane outriggers to ensure operational safety.

Expert Maintenance Tips:

• Pilot Pressure Adequacy: Ensure pilot pressure (usually supplied by the opposing line) is sufficient to overcome spring force and port pressure. Insufficient pilot pressure will prevent the poppet from opening fully, causing vibration or excessive pressure drops.

• Cleanliness Control: Poppet seals are highly sensitive to particulate contaminants. Debris trapped in the seat will lead to pressure loss. Maintain filtration of at least 10μm.

• Stack Bolt Torque: When installing sandwich stacks, use Grade 12.9 high-strength bolts and tighten them symmetrically to the recommended torque to prevent valve body distortion.