Z2FS6-2-4X/2Q Rexroth Twin Throttle Check Valve 315 Bar

Product Overview

The Z2FS6-2-4X/2Q is a Bosch Rexroth Z2FS Series twin throttle check valve in sandwich plate design. It is intended for main-flow or pilot-flow limitation of one or two actuator ports.

Unlike a conventional solenoid valve, the Z2FS is a mechanically actuated hydraulic flow-control valve. Two symmetrically arranged throttle check elements restrict flow in one direction while permitting low-resistance return flow in the opposite direction. The valve can be used for either supply throttling or discharge throttling depending on its installation orientation.

For the exact Z2FS6-2-4X/2Q configuration, Bosch Rexroth specifies:

• Size 6
• Component Series 4X
• Maximum operating pressure: 315 bar
• Maximum flow: 80 L/min
• ISO 4401-03-02-0-05 mounting pattern
• Sandwich plate construction
• Mechanical actuation
• NBR seals
• Setscrew with lock nut
• Standard adjustment configuration “2Q”.

For replacement applications, the standardized sandwich-plate interface provides a strong basis for direct interchangeability, while our replacement products can additionally be subjected to 100% simulated working-condition testing before delivery.

Technical Specifications

Z2FS6-2-4X/2Q

• Manufacturer: Bosch Rexroth
• Series: Z2FS
• Valve Type: Twin Throttle Check Valve
• Full Model: Z2FS6-2-4X/2Q
• Nominal Size: Size 6
• Component Series: 4X
• Mounting Type: Sandwich Plate
• Mounting Standard: DIN 24340 Form A / ISO 4401-03-02-0-05
• CETOP Size: D03
• Maximum Operating Pressure: 315 bar
• Maximum Flow: 80 L/min
• Adjustment: Setscrew with Lock Nut and Protective Cap
• Actuation: Mechanical
• Valve Function: Twin throttle check
• Flow Behavior: Throttled in one direction, free check flow in the opposite direction
• Application: Main flow limitation / pilot flow limitation
• Throttling Mode: Supply or discharge throttling
• Seal Material: NBR
• Compatible Fluids: HL, HLP, HLPD, HVLP, HVLPD, HFC
• Hydraulic Fluid Temperature: -20 to +80°C
• Ambient Temperature: -20 to +80°C
• Viscosity Range: 10–800 mm²/s
• Weight: Approximately 0.8 kg in the official Z2FS6 data; individual configured product records may show approximately 1.041 kg, so shipment weight should be checked against the exact ordering configuration.
• Displacement: Not applicable
• Rated Speed: Not applicable
• Peak Pressure: No separate higher peak-pressure value is stated for this configuration; the official specification is a maximum operating pressure of 315 bar.

Z2FS Family

The Z2FS family also includes Z2FS10, Z2FS16 and Z2FS22. Bosch Rexroth identifies them as twin throttle check valves in different nominal sizes. The official Rexroth catalog lists 31.5 MPa for Z2FS10 and 35 MPa for Z2FS16 and Z2FS22.

For Z2FS10, the current Rexroth selector confirms Size 10, Series 3X, multiple adjustment options, NBR/FKM sealing options, and supply/discharge throttling configurations.

Key Technical Advantages

1. Twin throttle-check architecture

The two internal throttle-check elements provide adjustable restriction in one direction and free check flow in the opposite direction. This makes the valve suitable for controlled actuator movement without requiring separate throttle and check valves.

2. Main-flow and pilot-flow control

The Z2FS can be installed for either main-flow limitation or pilot-flow limitation. In main-flow applications, it can control actuator velocity; in pilot circuits, it can influence the switching time of pilot-operated directional valves.

3. Supply or discharge throttling

The valve can be configured for supply throttling or discharge throttling by changing the installation orientation, allowing the same valve concept to support different hydraulic motion-control requirements.

4. Standard ISO sandwich-plate interface

The Z2FS6-2-4X/2Q uses an ISO 4401-03-02-0-05 mounting pattern. This standardized construction makes it suitable for integration into modular hydraulic valve stacks and replacement-oriented machine designs.

5. High-pressure capability

The Z2FS6-2-4X/2Q is rated for 315 bar maximum operating pressure with a maximum flow of 80 L/min, covering a broad range of industrial actuator-speed and pilot-flow applications.

6. Multiple adjustment configurations

The Z2FS product family is offered with several adjustment concepts, including setscrew/locknut, lockable rotary knobs and spindle-based adjustments, allowing the flow-control behavior to be matched to machine commissioning and maintenance requirements.

7. No electrical control required

The Z2FS6-2-4X/2Q is mechanically actuated. It does not require a solenoid, coil voltage or electronic amplifier for flow adjustment, which simplifies hydraulic control where purely mechanical metering is preferred.

Application Areas

Typical applications include:

• Industrial hydraulic power units
• Hydraulic presses
• Hydraulic clamping systems
• Injection molding machinery
• Metal forming equipment
• Machine tools
• Hydraulic cylinder speed control
• Hydraulic actuator motion control
• Pilot-operated directional valve circuits
• Industrial hydraulic manifolds

The main engineering function is controlled actuator speed regulation and pilot-flow limitation, rather than electrical solenoid switching.

Expert Maintenance Tips

Verify the exact ordering code

Do not identify a replacement only as Z2FS6 or Z2FS10. Verify the complete code, including nominal size, adjustment type, component series, sealing material and supply/discharge throttling configuration.

Do not treat the valve as a solenoid valve

The Z2FS6-2-4X/2Q is mechanically actuated, so there is no solenoid coil or control voltage to match.

Confirm the adjustment direction

Rexroth documentation specifies that left rotation increases flow while right rotation decreases flow for the applicable adjustment mechanisms. Adjust gradually while monitoring actuator speed and system pressure.

Select supply or discharge throttling correctly

The choice between meter-in and meter-out behavior can significantly affect actuator stability, particularly under overrunning loads. Confirm the hydraulic circuit before installation.

Maintain hydraulic cleanliness

Contamination can affect the internal throttle and check elements and may lead to unstable flow regulation or inconsistent return-flow behavior. Maintain appropriate filtration and clean hydraulic fluid.

Confirm the pilot circuit where applicable

When the Z2FS is used for pilot-flow limitation, verify the upstream and downstream pilot connections and ensure that the valve is installed in the correct orientation for the intended switching-time adjustment.