B8_4A... (EDB-A-VR)

Valve elements with 4 ways and 3 positions.

Control spools directly operated by solenoids with removable coils.

In the de-energized condition, the control spool is held in the central position by return springs.

Wet pin tubes for DC coils, with push rod for mechanical override; burnish surface treatment.

Single or Dual cross piloted check valves on A and B ports.

PO checks valves with 4:1 pilot ratio.

Coils can be rotated 360° around the tube.

Manual override (push-button or screw type) available as option.

Size 4

Series 00

Maximum operating pressure 250 bar (3625 psi)

Maximum flow 20 l/min (5.3 gpm)

Port connections G 3/8 SAE6 - M16x1.5

The sandwich plate design directional valve elements B8_4A... are very compact direct operated solenoid valves which control the start, the stop and the direction of the oil flow. These elements basically consist of a stackable housing (1) with a control spool (2), two solenoids (5), and two return springs (4). The upper part of the housing is extended in order to provide space for the cavities where two PO check valves are fitted. They consist of two calibrated balls (10), with return springs (11), which allow upstream flow but lock on the respective seats (9) and prevent the return flow. The return flow is possible when they are opened by the pilot piston (8), if enough pilot pressure is present in the opposite line. When energized, the force of the solenoid (5) pushes the control spool (2) from its neutral-central position “0” to the required end position “a” or “b”, and the required flow from P to A (with B to T), or P to B (with A to T) is achieved. Once the solenoid is de-energized, the return spring (4) pushes the spool thrust washer (3) back against the housing and the spool (2) returns in its neutral-central position.

Each coil is fastened to the solenoid tube by a ring nut (6). A pin (7) allows to push the spool (2) in emergency conditions, when the solenoid cannot be energized, like in case of voltage shortage.

Measured with hydraulic fluid ISO-VG32 at 45° ±5 °C (113° ±9 °F); ambient temperature 20 °C (68 °F).

The performance curves are measured with flow going across and coming back, like P>A and B>T, with symmetrical flow areas.

In case of special circuit connections, the performance limits can change.