Hydraulic-Pneumatic Interface Valves
Occupying about a third of the space required by conventional diaphragm interface valves, this three-way, two position, normally closed valve permits a low-pressure signal from an integral pneumatic pilot to control a high-pressure hydraulic power system. The pilot section handles pressures to 1,000 psi; the hydraulic section accommodates pressures to 10,000 psi.
In this unique spool valve design, the usual pilot diaphragm is replaced by a piston. The use of a stainless steel piston and compatible seal eliminates failures due to diaphragm leakage and incompatibility of diaphragm with process fluids.
A high ratio of hydraulic power pressure to pilot control pressure insures safe operation and positive control under all conditions. A pilot pressure of 50 psi controls 5,000 psi hydraulic power; 80 psi pilot pressure controls 10,000 psi hydraulic power pressure.
A soft seal design insures zero leakage in the hydraulic power section. Metal-to-metal seating insures against leakage in emergency situations.
Failsafe closure is insured, as both the internal spring and hydraulic pressure acting on the differential spool area provide sufficient force to effect closure, should one or the other fail. Normally both act to close the valve.
A positive indicator of operation is provided in the spool extension, which shifts to show position.
Excellent flow capacity is provided with a value of Cv=0.5 or the equivalent of an orifice of .224 inch diameter.
A normally open version of this valve is also available under product number 433242-P.
With minor differences the dimensions and operating parameters are the same for this version.
The manual override version has a turning handle located at top center of piston housing.
Specifications
| Complete assembly |
|
| Weight |
5.8 lbs. (2.6 Kg) |
| Pilot section |
|
| Fluid |
Air or hydraulic |
| Operating pressure |
50 psi (3.45 bar) air pressure for 5,000 psi (345
bar) hydraulic pressure |
| Working pressure |
1,000 psi (68.9 bar) maximum |
| Proof pressure |
1,500 psi (103.4 bar) |
| Burst pressure |
2,000 psi (137.9 bar) |
| Valve section |
|
| Fluid |
Hydraulic fluid or diesel |
| Working pressure |
10,000 psi (689 bar) maximum |
| Proof pressure |
15,000 psi (1034 bar) |
| Burst pressure |
20,000 psi (1379 bar) |
| Temperature range |
-65° to 450°F (-53° to 232°C) |
| Flow capacity |
Cv +0.5 |
| Flow |
39 GPM at 5,000 psi (147 liters per minute at 345 bar) |
| Internal leakage |
Zero |
| External leakage |
Zero |
Ordering Information
| Part No. |
Description |
| 183834-P |
6,000 psi working pressure, manual override, Viton seals |
| 433174-P |
6,000 psi working pressure, standard and H2S-CO2 service, Viton seals |
| 433174-PA |
6,000 psi working pressure, Arctic service, -65°F Buna-N seals |
| 433174-PH |
8,000 psi working pressure, standard and H2S-CO2 hydraulic pilot, Viton seals |
| 433174-PHA |
8,000 psi working pressure, Arctic hydraulic pilot, -65°F Buna-N seals |
| 433242-P |
6,000 psi working pressure, normally open, Viton seals |
| 433707-P |
6,000 psi working pressure, two inlet, Viton seals |
| 434189 |
10,000 psi working pressure, standard and H2S-CO2 service, Viton seals |
 |
