Principle of spot Rexroth balance valve FD25PA21/B04V

Spot Rexroth Balance Valve FD25PA21/B04VThe principle flow direction is from B to A. Fuel tank. The flow rate on one side of the cylinder piston rod matches the working conditions. The relationship between the control pressure of port X and the load pressure of port B is B=1:20. When the control pressure is reached, the main valve core will open in advance. The main valve core is open. By controlling the valve core (4) to lift the pilot stage (3) from its seat, the chamber (8) is depressurized through this borehole and interface.

Reduce pressure through this borehole and port A leading to the fuel tank. At the same time, the load pressure in port B no longer acts on chamber (8). Main valve core

(2) Therefore, uninstall. The reverse side of the control valve core (4) at the main valve core (2) rests against the collar of the damping valve core (5).

The collar of the damping valve core (5).

Criteria affecting the opening and closing time of the verification Q-meter

Guiding principle of time

▶ By controlling the throttle holes (6) in the valve core (4) and the throttle holes (6) on both sides of the damper, the opening sequence is throttled.

Control the throttle holes (6) on both sides of the valve core (4) and damping valve core (5) to throttle the opening sequence.

The throttle holes (6) on both sides of the valve core (5). The hole (6) is protected by a sieve.

▶ The closing motion of the one-way Q-value meter has almost no throttling.

When used together with a cylinder

When used with a cylinder, a throttle check valve (external control) can be installed on the control line leading to the X port

One way valve (outlet control) to affect the closing sequence.

When used with a motor, a throttle check valve should not be installed in the control pipeline of the X port.

In this case, it is recommended to set the control time of the directional valve to

Spot Rexroth Balance Valve FD25PA21/B04VSize Chart

FD 12 FA 2X/. ..

FD 16 FA 2X/. ..

FD 25 FA 2X/. ..

FD 32 FA 2X/. ..

FD 12 FA 2X/. ..

FD 16 FA 2X/. ..

FD 25 FA 2X/. ..

FD 32 FA 2X/. ..

Bypass valve, reverse free flow

Optional built-in secondary pressure relief valve (only applicable to valves with flange connections)

Only applicable to valves with flange connections)

▶ Used for installation in valve groups (plug-in valves)

▶ Equipped with SAE flange interface

▶ Used for base plate installation, interface mode complies with

-ISO 5781-06-07-00 (Dimensions 12, 16)

-ISO 5781-08-10-00 (size 25)

-ISO 5781-10-13-0-00 (size 32)

▶ When installing the valve panel, use a bottom plate type

application field

▶ construction machinery

▶crane

▶excavator

▶Material handling vehicle

▶drilling rig