R901031554 FD32 Flow Check Valve: Mounting & RFQ Guide

The R901031554 FD32 flow check valve corresponds to the Bosch Rexroth designation FD 32 KA2X/B06M. It belongs to the FD Check-Q-meter family used for load-control applications.

For replacement work, the important point is not simply “FD32.” The complete material number, mounting design, valve size, pilot arrangement, and installation interface should match the existing system.

Bosch Rexroth documentation identifies the FD family as pilot-operated, leakage-free Check-Q-meters for controlling returning flow from hydraulic actuators. The series covers sizes 12, 16, 25, and 32.

What Is the R901031554 FD32 Valve Used For?

The FD valve controls actuator movement when an overrunning load could cause a hydraulic motor or cylinder to accelerate beyond the commanded speed.

During free flow from A to B, the main poppet opens. During controlled return from B to A, pilot pressure at port X progressively opens the valve.

This arrangement provides several key functions:

• controlled return flow under changing load;

• load holding when pilot pressure is absent;

• free flow in the opposite direction;

• protection against uncontrolled actuator movement;

• an isolating function if a relevant hydraulic line fails.

Bosch Rexroth lists construction machinery, cranes, excavators, material handlers, drilling rigs, and stationary equipment among typical FD applications.

The FD series supports operating pressures up to 350 bar at ports A and X. The published maximum pressure at port B is 420 bar.

For size 32, the published maximum flow is 560 l/min. That is one reason FD32 should not be replaced simply with a smaller FD size based on external appearance.

How Does FD32 KA Mounting Affect Replacement?

This is the most important installation detail for R901031554.

The full designation is:

R901031554 — FD 32 KA2X/B06M

In the Rexroth FD type code, KA identifies manifold mounting in cartridge-valve form. It is different from the FA, FB, and PA mounting versions.

This distinction matters when a maintenance team describes the requirement only as an “FD32 flange valve.”

R901031554 is a KA version. A supplier should therefore verify the machined manifold interface rather than quote an FA or FB valve because both carry the FD32 size designation.

For FD32 KA, Rexroth publishes a substantially larger cartridge installation interface than FD16 KA.

Important FD32 KA dimensions include a M64 × 2 threaded feature, compared with M42 × 2 on FD16 KA. The fixing arrangement also changes from M10 hardware on FD16 to M16 hardware on FD32.

For replacement projects, useful mounting information includes:

• manifold cavity dimensions;

• A and B port arrangement;

• pilot port X position;

• mounting screw size;

• installation depth;

• available clearance around the valve;

• existing manifold drawing, if available.

A photograph of the old valve alone is not enough for a reliable mounting decision.

FD16 vs FD32: Why Nominal Size Matters

FD16 and FD32 belong to the same valve family, but they are not interchangeable sizes.

The difference affects hydraulic capacity and the physical manifold interface.

Bosch Rexroth specifies maximum flows of 200 l/min for size 16 and 560 l/min for size 32. The standard damping-orifice codes also differ between these sizes.

This means an FD16 cannot be treated as a smaller drop-in substitute for an FD32.

The manifold dimensions differ, and hydraulic capacity changes significantly. The correct choice must follow the circuit requirement and existing installation geometry.

R901031554 itself is independently listed as FD 32 KA2X/B06M, confirming that the requested material number belongs to the size-32 KA configuration.

R901031554 FD32 Mounting Checks Before Ordering

A replacement inquiry should go beyond confirming the first eight or ten digits of a material number.

For this valve, procurement teams should verify the following items before accepting a quotation.

1. Confirm R901031554 on the nameplate

Use the complete material number whenever it remains readable. Also photograph the complete type designation.

2. Confirm FD 32 rather than FD 16 or FD 25

The nominal size affects both flow capacity and installation geometry.

3. Confirm KA mounting

Do not substitute an FA, FB, or PA body without an engineering review. Those design codes represent different mounting arrangements.

4. Preserve the full /B06M suffix

The inquiry should reproduce the installed designation exactly.

Current FD documentation shows specific type-code options that may differ from older configurations. A supplier should not silently change a suffix to a current-looking code without confirming compatibility.

5. Check ports A, B, and X

Port A connects toward the control block, B toward the consumer, and X is the pilot-control connection in the documented FD circuit.

6. Compare pressure and flow

Record actual system pressure and expected flow, even when the original material number is known.

7. Check hydraulic fluid and operating conditions

Bosch Rexroth specifies hydraulic-fluid requirements, viscosity limits, temperature ranges, and cleanliness requirements for the FD family. These should be checked for the actual machine.

These checks are especially useful when the installed component is old or when purchasing records contain only a shortened model description.

How to Source R901031554 From a Rexroth Valve Supplier

For a commercial inquiry, asking only for “R901031554 price” can produce a quick quotation but not necessarily a technically complete one.

A better inquiry identifies the required configuration and gives the supplier enough information to distinguish an exact item from an alternative.

Include:

• Bosch Rexroth material number: R901031554;

• type code: FD 32 KA2X/B06M;

• required quantity;

• nameplate photograph;

• manifold or mounting-face photograph;

• application or machine type;

• normal and maximum pressure;

• expected flow;

• hydraulic fluid;

• destination country;

• required delivery date.

If the supplier offers a different material number, ask whether it is an exact successor, a functional alternative, or simply another FD32 configuration.

Nabor's Bosch Rexroth Valve product category provides a relevant internal route for buyers reviewing Rexroth hydraulic valve products. The site also supports product inquiries from individual valve pages.

For broader replacement checks, the Rexroth Valve Replacement Parts Guide recommends confirming material number, mounting, pressure, flow, fluid, and system information before comparing alternatives.

Buyers comparing valve architectures can also review Rexroth Check Valve: Cartridge vs Sandwich Options. That article explains why mounting architecture should be established before choosing by nominal size alone.

For R901031554, the most useful starting point remains the complete designation FD 32 KA2X/B06M.

Price, delivery, and availability can then be compared after the technical scope of each quotation is clear.

FAQ

Is R901031554 an FD16 or FD32 valve?

R901031554 corresponds to FD 32 KA2X/B06M, so it is a size-32 FD valve. It should not be ordered as an FD16 equivalent.

Can FD16 replace FD32 if the working pressure is the same?

Not as a direct size substitution. FD16 and FD32 have different maximum flow capacities and different KA manifold dimensions.

Does R901031554 use an SAE flange connection?

The complete type code contains KA, which Rexroth defines as manifold mounting in cartridge-valve form. SAE flange versions use FA or FB design codes.

What is the maximum flow for an FD32?

Bosch Rexroth RE 27551 lists a maximum flow of 560 l/min for size 32. Size 16 is listed at 200 l/min.

What does B06 indicate on an FD32?

For the documented FD series, B06 identifies a 0.6 mm damping orifice used with size 32. The full installed type code should still be retained when ordering.

What should I send when requesting an R901031554 quotation?

Send the full part number, type code, quantity, nameplate photo, mounting details, application, pressure, flow, destination, and required delivery date.

Reference Sources

1. Bosch Rexroth RE 27551 — FD Check-Q-Meter Technical Data
   Technical reference for FD function, sizes, mounting designs, pressure, flow, orifice options, applications, and installation data.

2. R901031554 — FD 32 KA2X/B06M Product Identification
   Product reference confirming the Bosch Rexroth material number and complete FD32 designation.

3. Nabor Bosch Rexroth Valve Products
   Relevant Nabor product category for Rexroth hydraulic valve sourcing and product inquiries.

4. Nabor Rexroth Check Valve: Cartridge vs Sandwich Options
   Supporting guidance on mounting architecture, valve selection, and replacement information.

5. Nabor Rexroth Valve Replacement Parts Guide
   Supporting RFQ guidance for part-number verification, mounting, pressure, flow, and replacement review.