Z2FS10-20B Rexroth Double Throttle Check Valve 315bar

Product Overview

Models such as Z2FS10-20B, Z2FS16-8-31/S2 and Z2FS22-3X/S belong to the Bosch Rexroth Z2FS series of sandwich-plate double throttle check valves. Featuring symmetrically arranged throttle-and-check elements, they comply with ISO 4401 mounting standards. Every unit undergoes rigorous 100% simulated operating-condition testing and offers excellent drop-in interchangeability for stacking directly between directional valves and subplates. Precise flow restriction in one direction and free reverse flow enable reliable actuator speed control in medium-to-high-pressure hydraulic systems.

Technical Specifications 

• Model examples: Z2FS10-20B, Z2FS16-8-31/S2, Z2FS22-3X/S
• Valve type: Sandwich-plate double throttle check valve
• Nominal size: 10 = NG10; 16 = NG16; 22 = NG25
• Mounting interface: ISO 4401
• Maximum operating pressure: 315–350 bar (depending on size)
• Maximum flow: approx. 160 l/min (NG10); approx. 250 l/min (NG16); approx. 360 l/min (NG22)
• Adjustment: Spindle with internal hexagon (with or without scale)
• Throttling type: S = supply throttling; S2 = discharge throttling
• Cracking pressure: approx. 0.3 bar
• Seal material: NBR or FKM
• Weight: approx. 3.1 kg (NG10); approx. 4.7 kg (NG16); approx. 8 kg (NG22)
• Hydraulic fluid compatibility: HL, HLP, HLPD, HVLP, HVLPD, etc.

Key Technical Advantages

1. Dual-channel symmetrical throttle design: Independent adjustment on A and B ports with free reverse flow through the check valve for precise actuator speed control.
2. Sandwich modular construction: Installs directly between directional valve and subplate/manifold, saving space and eliminating additional piping leakage points.
3. Excellent drop-in interchangeability: Strict compliance with ISO 4401 mounting face allows direct replacement of equivalent Rexroth Z2FS valves, minimizing modification costs and downtime.
4. High pressure and large flow capability: Rated up to 350 bar with high flow capacity for heavy-duty hydraulic systems.
5. Precise adjustment and long service life: Stable internal-hexagon spindle adjustment; hardened internal components provide strong contamination resistance and long-term reliability.

Application Areas

Injection moulding machines, die-casting machines, metal-forming equipment, machine-tool hydraulics, lifting equipment, mobile machinery, marine hydraulics and other medium-to-high-pressure circuits requiring precise actuator speed control.

Expert Maintenance Tips

1. Ensure mounting surfaces are clean and flat before installation; fit seals correctly and tighten specified bolts evenly to the recommended torque to prevent external leakage.
2. Maintain recommended fluid cleanliness per ISO 4406; use hydraulic fluids compatible with the installed seal material. Verify adjustment position before first start-up.
3. Adjust flow slowly with an internal-hexagon tool (clockwise usually decreases flow); lock after setting.
4. Periodically inspect the valve body and adjustment mechanism for leakage or sticking; clean and protect sealing surfaces during long-term storage.
5. Do not disassemble internal throttle and check valve components. Seal replacement or repairs should be performed only by technicians experienced with Rexroth products; always perform functional tests before returning the valve to service.