About Pressure-Relief Valves
More
Extended-Life Back-Pressure-Regulating Valves for Water and Oil
- For Use With: Water, Oil
- Temperature Range: -40° to 450° F
For a longer service than cast iron valves, these have a durable bronze body and a 303 stainless steel seal. Commonly installed as bypass lines after centrifugal, reciprocating, and rotary pumps, they obstruct flow to maintain sufficient operating pressure in your system. If the system pressure exceeds the set pressure, they exhaust through the outlet. Adjust the set pressure within the range.
For technical drawings and 3-D models, click on a part number.
Inlet | Outlet | |||||||
|---|---|---|---|---|---|---|---|---|
| Pipe Size  | Location | Max. Pressure, psi | Pipe Size | Location | Port-to-Port Lg. | Choose an Outlet Pressure Range, psi | Each | |
NPT Female | ||||||||
Bronze Body—303 Stainless Steel Seal | ||||||||
| 1/4 | Bottom | 600 | 1/4 | Side | 1 1/4" | 0000000 | 0000000 | |
| 3/8 | Bottom | 600 | 3/8 | Side | 1 1/4" | 0000000 | 000000 | |
| 1/2 | Bottom | 600 | 1/2 | Side | 1 5/8" | 0000000 | 000000 | |
| 3/4 | Bottom | 600 | 3/4 | Side | 1 5/8" | 0000000 | 000000 | |
| 1 | Bottom | 600 | 1 | Side | 2 1/4" | 0000000 | 000000 | |
| 1 1/4 | Bottom | 600 | 1 1/4 | Side | 2 1/4" | 0000000 | 000000 | |
Back-Pressure-Regulating Valves for Water and Oil
- For Use With: Water, Oil
- Temperature Range: -40° to 200° F
Commonly used as bypass lines after centrifugal, reciprocating, and rotary pumps, these valves obstruct flow to maintain sufficient operating pressure in your system. If the system pressure exceeds the set pressure, they exhaust through the threaded relief port. Adjust the set pressure within the range. Valves have a cast iron body that absorbs vibration from pressure changes to reduce wear and noise in your pipeline.
For technical drawings and 3-D models, click on a part number.
Inlet | Outlet | Relief Port | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Pipe Size | Location | Max. Pressure, psi | Pipe Size | Location | Pipe Size | Location | End-to-End Lg. | Choose an Outlet Pressure Range, psi | Each | |
NPT Female | ||||||||||
Cast Iron Body—Nickel Alloy Diaphragm and 303 Stainless Steel Seal | ||||||||||
| 1/2 | Side | 400 | 1/2 | Side | 1/2 | Bottom | 2 7/8" | 0000000 | 000000000 | |
| 1 1/4 | Side | 400 | 1 1/4 | Side | 1 1/4 | Bottom | 4 1/4" | 0000000 | 00000000 | |
| 1 1/2 | Side | 400 | 1 1/2 | Side | 1 1/2 | Bottom | 5" | 0000000 | 00000000 | |
| 2 | Side | 400 | 2 | Side | 2 | Bottom | 5" | 0000000 | 00000000 | |
Panel-Mount Back-Pressure-Regulating Valves for Air and Inert Gas
- For Use With: Air, Inert Gas
- Temperature Range: 40° to 150° F
Threads below the adjustment knob and an included panel-mount nut allow you to add these valves to your instrument panel. Often used in systems running on air compressors, they're installed after pressure-sensitive equipment to obstruct flow and maintain a consistent operating pressure. If the system pressure exceeds the set pressure, they exhaust through the outlet. Adjust the set pressure within the range.
For technical drawings and 3-D models, click on a part number.
Inlet | Outlet | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Pipe Size | Thread Size | Location | Max. Pressure, psi | Pipe Size | Thread Size | Location | End-to-End Lg. | Panel Cutout Dia. | Choose an Outlet Pressure Range, psi | Each | |
NPT Female | |||||||||||
Polysulfone Body—Buna-N Diaphragm and Silicone Seal | |||||||||||
| 1/8 | __ | Side | 100 | 1/8 | __ | Side | 1 1/8" | 9/16" | 00000000 | 000000 | |
UNF Female | |||||||||||
Polysulfone Body—Buna-N Diaphragm and Silicone Seal | |||||||||||
| __ | 10-32 | Side | 100 | __ | 10-32 | Side | 1 1/8" | 9/16" | 00000000 | 00000 | |
Back-Pressure-Regulating Valves for Air and Inert Gas
- For Use With: Air, Inert Gas
- Temperature Range: 0° to 150° F
Often used to protect equipment running on air compressors, these valves obstruct flow to maintain sufficient operating pressure in your system. If the system pressure exceeds the set pressure, they exhaust through the unthreaded relief port. Adjust the set pressure within the range. Valves have two gauge ports.
For technical drawings and 3-D models, click on a part number.
Inlet | Outlet | Gauge Port | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Pipe Size | Location | Max. Pressure, psi | Pipe Size | Location | Pipe Size | Location | End-to-End Lg. | Choose an Outlet Pressure Range, psi | Each | |
NPT Female | ||||||||||
Aluminum Body—Buna-N Diaphragm and Seal | ||||||||||
| 1/4 | Side | 250 | 1/4 | Side | 1/4 | Side | 3" | 0000000 | 0000000 | |
| 3/8 | Side | 250 | 3/8 | Side | 1/4 | Side | 3" | 0000000 | 000000 | |
| 1/2 | Side | 250 | 1/2 | Side | 1/4 | Side | 3" | 0000000 | 000000 | |
Sanitary Back-Pressure-Regulating Valves
- For Use With: Food and Beverage
- Temperature Range: -40° to 120°F
- Specifications Met: 3-A Certified 64-00, ANSI/FCI 70-2 Class III, FDA Compliant 21 CFR 177.2600
Designed to meet 3-A sanitary standards, these valves regulate liquid, gas, and air pressure in hygienic zones of food and beverage plants. They’re often used at the end of pipelines on processing and sanitizing equipment. Made of 316 stainless steel, they won't corrode from frequent washdowns with harsh cleaners. With an extremely smooth interior that self-drains, bacteria won't have time or space to grow. The spring and internal valve mechanisms are sealed off behind the diaphragm, which also prevents contamination. They connect with quick-clamp fittings, so disassembling to clean your line takes little time.
These valves obstruct flow to maintain sufficient operating pressure in your system. If the system pressure exceeds the set pressure, they exhaust through the outlet. They meet ANSI/FCI 70-2 Class III standards for shut-off valves, meaning a maximum of 0.1% of fluid, gas, or air will escape through the outlet when they’re closed. An integrated T-handle lets you set the outlet pressure without additional tools. The diaphragm and seal resist repeated exposure to water, and they’re FDA compliant for direct contact with food.
For technical drawings and 3-D models, click on a part number.
Inlet | Outlet | Lg. | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| For Tube OD | Flange OD | Location | Max. Pressure, psi | For Tube OD | Flange OD | Location | End-to-End | Port-to-Port | Choose an Outlet Pressure Range, psi | Each | |
Quick Clamp | |||||||||||
316 Stainless Steel Body—EPDM Diaphragm and EPDMSeal | |||||||||||
| 3/4" | 0.984" | Side | 200 | 3/4" | 0.984" | Bottom | 6 5/8" | 3 9/32" | 000000 | 000000000 | |
| 1" | 1.984" | Side | 200 | 1" | 1.984" | Bottom | 6 11/16" | 3 5/16" | 000000 | 00000000 | |
316 Stainless Steel Body—PTFE Plastic Diaphragm and EPDMSeal | |||||||||||
| 2" | 2.516" | Side | 100 | 2" | 2.516" | Bottom | 11 5/8" | 5 3/4" | 000000 | 00000000 | |
Adjustable Inline Pressure-Relief Valves for Chemicals
- For Use With: Potassium Sulfate, Sodium Hypochlorite
- Temperature Range: 0° to 140° F
With a three-port design, these valves allow inline flow from the inlet to the outlet during normal conditions and divert flow through the relief port in overpressure conditions. Often used with feed pumps for fertilizers and bleach, they have a PVC body and a PTFE seal for excellent chemical resistance. The relief port begins opening at the set pressure and fully opens at about 10% over the set pressure. It begins closing as pressure drops and fully closes when the system pressure is restored below the set pressure, resuming inline flow from the inlet to the outlet. Adjust the set pressure within the range.
For technical drawings and 3-D models, click on a part number.
Inlet | Outlet | Relief Port | Set Pressure | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Pipe Size | Location | Maximum Pressure, psi | Pipe Size | Location | Pipe Size | Location | Range, psi | Adjustment Method | Overall Ht. | Each | |
NPT Female Inlet, Outlet, and Relief Port | |||||||||||
Dark Gray PVC Body—PTFE Seal | |||||||||||
| 1/4 | Side | 350 | 1/4 | Side | 1/4 | Bottom | 10 to 150 | External Adjustment Screw | 3 17/32" | 00000000 | 0000000 |
| 1/2 | Side | 350 | 1/2 | Side | 1/2 | Bottom | 10 to 250 | External Adjustment Screw | 5 9/16" | 00000000 | 000000 |
| 1 | Side | 350 | 1 | Side | 1 | Bottom | 10 to 250 | External Adjustment Screw | 5 7/8" | 00000000 | 000000 |