Valves of type FES are pilot-operated 2-way proportional throttle valves for block installation for the continuous control of flows.
Technical set-up:
The valve consists of four main assemblies:
- Cover (1) with connection surface for pilot oil connections
- Main valve (2) with orifice spool (3)
- Pilot control valve (4) with proportional solenoid (5)
General function:
- Command value-dependent position control of the orifice spool (3) and thus defined opening of the orifice (8).
- The flow depends on the Δp across the orifice (8) and the position of the orifice spool (3).
- Actual value recording of the orifice spool (3) position by the position transducer (7); command/actual value comparison in the electronics (6); variations are prepared and forwarded as control output for correction of the orifice spool (3) position to the proportional solenoid (5) to the pilot control valve (4).
- Area ratio of area (14) to area (15) = 2 : 1 for NG25; 32; 40 and 1.6 : 1 for NG50; 63.
- Flow direction A → B (connect X to A);
- Flow direction B → A (connect X to B);
- External pilot oil supply possible via X.
- When the enable is disconnected, the orifice spool (3) will move onto the valve seat (9) and block the flow direction A → B in a leakage oil-free manner. The spool seal (11) seals port B to the control chamber (12) in a leakage oil-free manner; with internal pilot oil supply observe leakage oil from X via the pilot control valve to Y!
- Orifice spool position at command value 0 V or 4 mA already regulated, whereas the orifice (8) is still located in the positive overlap.
Open orifice spool function:
(Assumption flow A → B and A connected to X)
- The proportional solenoid (5) moves the pilot spool (4.1) against the spring (13) and opens the connection from control chamber (12) to Y; pressure reduction in the control chamber (12) and movement of orifice spool (3) in opening direction by the pressure in A on the area (15) plus the pressure n B on the annulus area (16).
Close orifice spool function:
(Assumption flow A → B and A connected to X)
- Flow reduction in the proportional solenoid (5); the spring (13) moves the pilot spool (4.1) against the proportional solenoid and opens the connection from X to the control chamber (12); pressure build-up in the control chamber (12); pressure on the areas (14) plus spring force (10) move the orifice spool (3) in closing direction
Flow control function:
- Can be used in connection with a pressure compensator for the load-compensated control of a flow
Supply voltage failure:
- The integrated electronics de-energize the solenoid in case of supply voltage failure or cable break in the position transducer (7)
- The pressure applied to control port X plus the spring force (10) move the spool onto the valve seat (9) where it blocks the flow A → B.
Notice;
Failure of the supply voltage will lead to an abrupt standstill of the control axis. The acceleration forces occurring in this connection may cause machine damage!
Type FESE..CA-3X/…
Type FES..CA-3X/…
- Size 25, 32, 40, 50, 63
- Component series 3X
- Max. operating pressure 315 bar
