FunctionWH valves are fluidically operated directional spool valves. They are used for the control of stop, start and direction of a flow.The directional valves mainly consist of housing (1), the cont...
Product Detail
Function
WH valves are fluidically operated directional spool valves. They are used for the control of stop, start and direction of a flow.
The directional valves mainly consist of housing (1), the control spool (2), one or two return springs (3), cover (4).
In the non-operated condition, control spool (3) is held by return springs (4) in the central or initial position (except for impulse spools).
Control spool (3) is shifted by the actuating elements to the required spool position.
Without return spring, without detent, type..O/...
(Only for Spool Symbol A,C,D)
When actuating elements without return springs and without detent are used, a defined spool position is not provided in the on-operated condition.
With detent, type..OF/..
(Only for Spool Symbol A,C,D)
Directional valves with hydraulic or pneumatic actuation, are also available as 2-position valves with detent. When actuating elements with detent are used, each spool position can be fixed.
Cartridge throttle
The use of a throttle insert is required when, due to the prevailing operating conditions, flows can occur during the switching process that are higher than permitted by the performance limits of the valve.
It is to be inserted in the P-channel of the directional valve.
Symbols
Ordering code
Technical data
| Valve type | WH | |
| Weight 1 operating cylinder kg | 2.0 | |
| 2 operating cylinder kg | 2.2 | |
| Fluid temperature range ℃ | -30 to+80 (NBR seal) | |
| -20 to+80(FKM seal) | ||
| Max.operating pressure | Port A,B,P bar | 315 |
| Port T bar | 160 | |
| Min control pressure bar | 6-10 | |
| Max control pressure bar | 200 | |
| Max.flow-rate L/min | 60 | |
| Flow cross section | Type Q m㎡ | For symbol Q 6% of nominal cross section |
| (switching neutral position) | Type W m㎡ | For symbol W 3% of nominal cross section |
| Control pressure bar | Min.6 to 10>tank pressure, Max.200 | |
| Fluid | Mineral oil, Phosphate ester | |
| Viscosity range m㎡/s | 2.8 to 500 | |
| Degree of contamination | Maximum permissible degree of fluid contamination: Class 9. NAS 1638 or 20/18/15,ISO4406 | |
Characteristic curves (Measured at θₒᵢₗ=40℃±5℃, using HL P46)
| Spool | Flow direction | |||
| P toA | P to B | A to T | B to T | |
| AB | 3 | 3 | - | - |
| C | 1 | 1 | 3 | 1 |
| DY | 5 | 5 | 3 | 3 |
| E | 3 | 3 | 1 | 1 |
| F | 1 | 3 | 1 | 1 |
| T | 10 | 10 | 9 | 9 |
| H | 2 | 4 | 2 | 2 |
| JQ | 1 | 1 | 2 | 1 |
| L | 3 | 3 | 4 | 9 |
| M | 2 | 4 | 3 | 3 |
| P | 3 | 1 | 1 | 1 |
| R | 5 | 5 | 4 | - |
| V | 1 | 2 | 1 | 1 |
| W | 1 | 1 | 2 | 2 |
| U | 3 | 3 | 9 | 4 |
| G | 6 | 6 | 9 | 9 |
With tank pressure is increased, the minimum control pressure must be increased according to this curve.
Operating limitation
Because of the adhesive effect, the switching function of the valves depends on the filtration. In order to achieve the specified admissible flow values, we recommend full flow filtration with 25 µm. The flow forces acting within the valves also affect the flow performance. With 4 way valves the specified flow data thus apply to normal operation with 2 volume flow directions (e.g. from P to A and at the same time return flow from B to T) (see table).
If only one flow direction is available, in critical cases, the admissible flow can be significantly smaller (e.g. when using a 4 way valve as 3 way valve, due to blocked connection A or B).
| Control pressure 6bar > T-pressure | ||
| Curve | Spool | |
| Return spring | 1 | A,B |
| 2 | C,D,Y | |
| 3 | E,J,L,U,M,Q,V,W | |
| 4 | F,P | |
| 5 | T | |
| 6 | G,H | |
| 7 | R | |
| .../OF....../O... | 8 | A,C,D |
| Control pressure 10bar> T-pressure | ||
| Curve | Spool | |
| Return spring | 1 | A,B |
| 8 | C,D,Y,E,G,H,J,L | |
| U,M,Q,V,W | ||
| 9 | F,P | |
| 10 | R | |
| 11 | T | |
| .../OF... .../0... | 8 | A,C,D |
Unit dimensions (WH)
