Model PRH-04-FLG |
PRESSURE-REDUCING VALVE (PRESSURE REGULATOR) |
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See also threaded NPT model PRH-04 THD
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Features
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Applications
Valve can be used for non-corrosive or mildly corrosive fluids, depending on the compatible materials selected. When liquids or gases contain debris or other solid matter which might cause internal clogging or improper operation of the valve, a strainer or filter with a fine wire mesh should be installed before the inlet of the valve. In-line strainer fittings or basket strainers can be purchased from Stra-Val to solve this problem. For this reason, this valve, as with most metal-seated regulators, should not be used for dead ended, shutoff service, or where the valve is operating at or near zero flow. When the valve is expected to be subjected to prolonged periods of shutoff, install a separate shutoff or isolation valve at the inlet of the valve. Always install a relief valve on the outlet side of the valve to handle any overpressure that may result from seat buildup or particle contamination.
This valve will work quite well on applications where the inlet pressure will fluctuate widely as it is a balanced inlet design.
We now offer some models that meet NACE MR0175. These are not priced on line. Consult factory.
Principle of Operation
This valve operates with a compression spring acting on the main valve which is used to adjust the outlet pressure with an adjusting screw. Therefore a desired increase in outlet pressure requires an increase in spring compression. Similarly, to get a reduction in outlet pressure requires a reduction in spring compression. The adjusting screw is locked in position with a lock nut. However, locking caps or a locking wire seal are also available to prevent tampering. The spring chamber which is non-wetted and does not come in contact with the fluid or gas is normally constructed in carbon steel (painted) but can be upgraded to stainless steel type 303SS and 316SS. The valve can operate in any orientation, vertical, as illustrated, or horizontal, etc.
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| PRH-04-FLG |
| 1. | Adjusting screw | Steel | |
| 2. | Lock nut | Steel | |
| 3. | Spring chamber | Steel | |
| 4. | Spring pusher | Steel | |
| 5. | Spring | Steel | |
| 6. | Spring carrier | Steel | |
| 7. | Main valve | Stainless steel | |
| 8. | Packing nut | Stainless steel | |
| 9. | V-rings packing | Teflon | |
| 10. | Retaining screw | Steel | |
| 11. | Body | Stainless steel |
Dimensions (in) Max for 600# flange
| A | B | C | D | Flow Cv |
|---|---|---|---|---|
| 1/2 | 2.75 | 2.75 | 11.75 | 3.93 |
| 3/4 | 3.25 | 3.50 | 13 | 4.91 |
| 1 | 3.50 | 3.50 | 15 | 9.57 |
| 1-1/4 | 4.00 | 4.25 | 16 | 12.1 |
| 1-1/2 | 4.25 | 4.50 | 16.5 | 17.1 |
| 2 | 5.50 | 5.50 | 17.5 | 35.3 |
Note: Dimensions are approximate and are subject to change without notice. Request certified dimensions before final product installation.
To show prices:
Click on a size: |
1/2" PRH04-05-FLG (call for pricing) |
3/4" PRH04-07-FLG (call for pricing) |
1" PRH04-10-FLG (call for pricing) |
1 1/4" PRH04-12-FLG (call for pricing) |
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1 1/2" PRH04-15-FLG (call for pricing) |
2" PRH04-20-FLG (call for pricing) |
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To price or order, first select a size above.
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