Proportional Directional Valve 4WRZ25E1-220-7X/6EG24N9TK4/M - Bosch Rexroth R900977678

Plants with a pressure-controlled pump lower system pressure during holding phases, yet pilot control still needs its minimum pressure. The 4WRZ25E1-220-7X/6EG24N9TK4/M is fed externally for that reason and controls 220 l/min nominal flow with spool symbol E1.

Benefits

• External pilot supply, the minimum pilot pressure is kept even when system pressure is lowered.
• Internal return through the tank channel, only one additional line has to be routed.
• 220 l/min nominal flow, flow up to 870 l/min, spool symbol E1 in size 25.
• 18.2 kg weight, 350 bar maximum operating pressure on the ISO 4401-08-08-0-05 pattern.
• Concealed auxiliary actuation, commanded at 24 VDC through an external amplifier.

Applications

This arrangement is found on plastics machinery and test rigs whose pump alternates between working and holding pressure. A dedicated pilot branch keeps the control loop able to work. The tank channel is enough for the drain as long as its back pressure stays within limits.

Manufacturer

Bosch Rexroth, material number R900977678. Minimum pilot pressure and permitted back pressure are given in data sheet RE 29115, range overview in RE 07600-B.