Bosch Rexroth R971893712

The isolator valve type Z2S is a releasable check valve in sandwich plate design. It is used for the leakage-free blocking of one or two actuator ports, also in case of longer standstill times. In direction A① to A② or B① to B②, there is a free flow; in the opposite direction, the flow is blocked. If, for example, there is a flow through the valve in direction A① to A②, the control spool (1) is moved in the direction of the B side, opens the ball seat valve (2) and then pushes the poppet (3) off its seat. Hydraulic fluid can now flow from B➁ to B➀. In order to allow the ball seat valve (2) to be safely closed, the control spool (1) must be hydraulically unloaded (see circuit example). Pre-opening

• Due to the pre-opening, there is a damped decompression of the pressurized liquid. Thus, possible switching shocks are avoided.

• The two-stage set-up with an increased control open ratio means even low pilot pressure can be unloaded securely.

Type Z2S 16 ‒… Type Z2S 16 A… Type Z2S 16 A…SO40 Type Z2S 16 A…SO60 Circuit example, schematic

1	Control spool, area A2
2	Ball, area A3
3	Poppet, area A1
4	Stop
5	Control spool, area A4

①	component side
②	plate side