About Pressure-Relief Valves
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ASME-Code Fast-Acting Pressure-Relief Valves for Steam
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- For Use With: Steam
- Temperature Range: -60° to 400° F
These valves meet ASME Code Section I for use with steam power boilers requiring pressure relief above 15 psi. They spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. For remote discharge, attach a drain line to the threaded relief port. Valves have a durable bronze body for a long service life.
EPR rubber seals provide better leak protection than brass seals.
Swivel test levers rotate 360° around the valve for use in areas with limited clearance.
For technical drawings and 3-D models, click on a part number.
Inlet | Relief Port | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Pipe Size | Location | Maximum Pressure, psi | Pipe Size | Location | Overall Ht. | Test Mechanism | Test Lever Type | Valve Type | Specifications Met | Choose a Set Pressure, psi | Each | |
NPT Male Inlet and NPT Female Relief Port | ||||||||||||
Bronze Body—Brass Seal | ||||||||||||
1/2 | Bottom | 250 | 3/4 | Side | 6 1/2" | Lever | __ | Pop Safety | ASME BPVC.I | 0000000 | 0000000 | |
1/2 | Bottom | 250 | 3/4 | Side | 7 5/16" | Lever | Swivel | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
3/4 | Bottom | 250 | 1 | Side | 7 1/2" | Lever | __ | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
3/4 | Bottom | 250 | 3/4 | Side | 7 5/16" | Lever | Swivel | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
1 | Bottom | 250 | 1 | Side | 7 5/8" | Lever | Swivel | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
1 | Bottom | 250 | 1 1/4 | Side | 8 1/2" | Lever | __ | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
1 1/4 | Bottom | 250 | 1 1/2 | Side | 9 5/8" | Lever | __ | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
1 1/2 | Bottom | 250 | 1 1/2 | Side | 9 5/8" | Lever | Swivel | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
1 1/2 | Bottom | 250 | 2 | Side | 10 5/8" | Lever | __ | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
2 | Bottom | 250 | 2 1/2 | Side | 13 5/8" | Lever | __ | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
Bronze Body—EPR Seal | ||||||||||||
1/2 | Bottom | 250 | 3/4 | Side | 6 1/2" | Lever | __ | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
3/4 | Bottom | 250 | 1 | Side | 7 1/2" | Lever | __ | Pop Safety | ASME BPVC.I | 0000000 | 000000 | |
1 | Bottom | 250 | 1 1/4 | Side | 8 1/2" | Lever | __ | Pop Safety | ASME BPVC.I | 0000000 | 000000 |
ASME-Code Fast-Acting Pressure-Relief Valves for Low-Pressure Steam
- For Use With: Steam
- Specifications Met: ASME BPVC.IV
- Max. Temperature: 250° F
For use with low-pressure steam-heating boilers requiring pressure relief at 15 psi, these valves meet ASME Code Section IV. All spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. Body is bronze for durability and a long service life.
Vented relief ports exhaust discharge directly.
Threaded relief ports can be attached to a drain line for remote discharge.
For technical drawings and 3-D models, click on a part number.
![](/prerenderstable/mvPRE/contents/gfx/imagecache/469/4699k29p1-c03a-digital@halfx_636856140220440258.png?ver=imagenotfound)
Inlet | Relief Port | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Pipe Size | Connection | Location | Maximum Pressure, psi | Connection Type | Location | Steam Flow Capacity, lbs./hr. | Set Pressure, psi | Overall Ht. | Test Mechanism | Valve Type | Each | |
Bronze Body—EPDM Seal | ||||||||||||
3/4 | NPT Male | Bottom | 15 | Vent | Top | 410 | 15 | 2 7/8" | Lever | Pop Safety | 0000000 | 000000 |
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Inlet | Relief Port | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Pipe Size | Connection | Location | Maximum Pressure, psi | Pipe Size | Connection | Location | Steam Flow Capacity, lbs./hr. | Set Pressure, psi | Overall Ht. | Test Mechanism | Valve Type | Each | |
Bronze Body—PTFE-Coated EPDM Seal | |||||||||||||
3/4 | NPT Male | Bottom | 15 | 3/4 | NPT Female | Side | 470 | 15 | 3 13/16" | Lever | Pop Safety | 0000000 | 000000 |
1 | NPT Male | Bottom | 15 | 1 | NPT Female | Side | 640 | 15 | 4" | Lever | Pop Safety | 0000000 | 00000 |
1 1/4 | NPT Male | Bottom | 15 | 1 1/2 | NPT Female | Side | 1,200 | 15 | 4 1/2" | Lever | Pop Safety | 0000000 | 000000 |
1 1/2 | NPT Male | Bottom | 15 | 2 | NPT Female | Side | 1,900 | 15 | 5 1/4" | Lever | Pop Safety | 0000000 | 000000 |
2 | NPT Male | Bottom | 15 | 2 | NPT Female | Side | 2,500 | 15 | 6 9/16" | Lever | Pop Safety | 000000 | 000000 |
2 1/2 | NPT Male | Bottom | 15 | 2 1/2 | NPT Female | Side | 3,520 | 15 | 8 1/8" | Lever | Pop Safety | 000000 | 000000 |
3 | NPT Male | Bottom | 15 | 3 | NPT Female | Side | 4,100 | 15 | 9 1/16" | Lever | Pop Safety | 000000 | 000000 |
Fast-Acting Pressure-Relief Valves for Ultra-Low-Pressure Steam
- For Use With: Steam
- Max. Temperature: 250° F
Choose these valves for small steam-heating boilers requiring pressure relief between 5 psi and 12 psi. They spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. All have a bronze body for durability and a long service life.
Vented relief ports exhaust discharge directly.
Threaded relief ports can be attached to a drain line for remote discharge.
For technical drawings and 3-D models, click on a part number.
ASME-Code Fast-Acting Pressure-Relief Valves for Water
![](/prerenderstable/mvPRE/contents/gfx/imagecache/627/6270t111p1-c03a-digital@halfx_636855920611929328.png?ver=imagenotfound)
- For Use With: Water
- Temperature Range: -60° to 406° F
These valves meet ASME Code Section VIII for use with water pressure vessels. They spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. All have a threaded relief port that can be attached to a drain line for remote discharge. Body is bronze for durability and a long service life.
For technical drawings and 3-D models, click on a part number.
Inlet | Relief Port | ||||||||
---|---|---|---|---|---|---|---|---|---|
Pipe Size | Location | Pipe Size | Location | Overall Ht. | Valve Type | Specifications Met | Choose a Set Pressure, psi | Each | |
NPT Male Inlet and NPT Female Relief Port | |||||||||
Bronze Body—316 Stainless Steel Seal | |||||||||
1/2 | Bottom | 3/4 | Side | 7 1/2" | Pop Safety | ASME BPVC.VIII | 0000000 | 0000000 | |
3/4 | Bottom | 3/4 | Side | 7 1/2" | Pop Safety | ASME BPVC.VIII | 0000000 | 000000 | |
1 | Bottom | 1 1/4 | Side | 9" | Pop Safety | ASME BPVC.VIII | 0000000 | 000000 | |
1 1/2 | Bottom | 2 | Side | 13 1/4" | Pop Safety | ASME BPVC.VIII | 0000000 | 000000 |
ASME-Code Fast-Acting Pressure-Relief Valves for Hot Water
![](/prerenderstable/mvPRE/contents/gfx/imagecache/470/4702k11p1-c03a-digital@halfx_636856130681074116.png?ver=imagenotfound)
- For Use With: Water
- Specifications Met: ASME BPVC.IV
- Temperature Range: 33° to 250° F
Protect your water-heating system with these valves that meet ASME Code Section IV for hot water heaters and boilers. They spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. All have a threaded relief port that can be attached to a drain line for remote discharge. Valves have a durable bronze body for a long service life.
For technical drawings and 3-D models, click on a part number.
Inlet | Relief Port | ||||||||
---|---|---|---|---|---|---|---|---|---|
Pipe Size | Location | Pipe Size | Location | Overall Ht. | Test Mechanism | Valve Type | Choose a Set Pressure, psi | Each | |
NPT Female Inlet and Relief Port | |||||||||
Bronze Body—Silicone Seal | |||||||||
3/4 | Bottom | 3/4 | Side | 5 5/16" | Lever | Pop Safety | 0000000 | 0000000 | |
3/4 | Bottom | 1 | Side | 5 5/16" | Lever | Pop Safety | 0000000 | 000000 | |
1 | Bottom | 1 | Side | 6 3/4" | Lever | Pop Safety | 0000000 | 000000 | |
1 | Bottom | 1 1/4 | Side | 6 3/4" | Lever | Pop Safety | 0000000 | 000000 | |
1 1/4 | Bottom | 1 1/2 | Side | 8 3/8" | Lever | Pop Safety | 0000000 | 000000 | |
1 1/2 | Bottom | 2 | Side | 10 13/16" | Lever | Pop Safety | 0000000 | 000000 | |
2 | Bottom | 2 | Side | 14" | Lever | Pop Safety | 0000000 | 000000 |
Fast-Acting Temperature- and Pressure-Relief Valves for Hot Water
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- For Use With: Water
- Specifications Met:
Pipe size of 3/4-2: ASME BPVC.IV
Pipe size of 1/2-2: CSA Certified - Max. Temperature: 210° F
Also known as T & P valves, these open when water temperature reaches 210° F or at the set pressure. They are commonly used with water heaters and storage tanks. All spring fully open at a water temperature of 210° F or the set pressure and remain open until the system is restored below the set point. For remote discharge, valves have a threaded relief port to attach a drain line. Body is bronze for durability and a long service life.
Valves with 3/4 to 2 pipe size meet ASME Code Section IV for hot water.
Valves with an extended body are designed for installation through thick insulation.
For technical drawings and 3-D models, click on a part number.
Inlet | Relief Port | Set | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Pipe Size | Location | Maximum Pressure, psi | Pipe Size | Location | Pressure | Temperature, °F | Water Flow Capacity, Btu/hr. | Features | Fits Insulation Thick. | Insertion Lg. | Valve Ht. | Overall Ht. | Test Mechanism | Valve Type | Each | |
NPT Female Inlet and NPT Female Relief Port | ||||||||||||||||
Bronze Body—Silicone Seal | ||||||||||||||||
3/4 | Bottom | 125 | 3/4 | Side | 125 | 210° | 185,000 | __ | __ | 3" | 5 7/8" | 8 7/8" | Lever | Pop Safety | 0000000 | 0000000 |
3/4 | Bottom | 150 | 3/4 | Side | 150 | 210° | 185,000 | __ | __ | 3" | 5 7/8" | 8 7/8" | Lever | Pop Safety | 0000000 | 000000 |
NPT Male Inlet and NPT Female Relief Port | ||||||||||||||||
Bronze Body—Silicone Seal | ||||||||||||||||
1/2 | Bottom | 150 | 1/2 | Side | 150 | 210° | 15,000 | __ | __ | 1 7/16" | 3 1/4" | 4 11/16" | Lever | Pop Safety | 0000000 | 00000 |
3/4 | Bottom | 150 | 3/4 | Side | 150 | 210° | 95,000 | __ | __ | 1 7/16" | 3 1/4" | 4 11/16" | Lever | Pop Safety | 0000000 | 00000 |
3/4 | Bottom | 150 | 3/4 | Side | 150 | 210° | 105,000 | __ | __ | 3" | 3 1/4" | 6 1/4" | Lever | Pop Safety | 0000000 | 00000 |
3/4 | Bottom | 165 | 3/4 | Side | 150 | 210° | 105,000 | Extended Body | 1 1/4" | 2 1/2" | 4 3/4" | 7 1/4" | Lever | Pop Safety | 0000000 | 00000 |
3/4 | Bottom | 165 | 3/4 | Side | 150 | 210° | 1,438,000 | Extended Body | 1 5/8" | 3 1/2" | 6 5/8" | 10 1/8" | Lever | Pop Safety | 0000000 | 000000 |
3/4 | Bottom | 165 | 3/4 | Side | 150 | 210° | 1,438,000 | Extended Body | 3 5/8" | 5" | 8 5/8" | 13 5/8" | Lever | Pop Safety | 0000000 | 000000 |
1 | Bottom | 165 | 1 | Side | 150 | 210° | 2,135,000 | __ | __ | 2" | 6 1/4" | 8 1/4" | Lever | Pop Safety | 0000000 | 000000 |
1 | Bottom | 165 | 1 | Side | 150 | 210° | 2,135,000 | __ | __ | 4" | 6 1/4" | 10 1/4" | Lever | Pop Safety | 0000000 | 000000 |
2 | Bottom | 150 | 1 1/2 | Side | 150 | 210° | 1,200,000 | __ | __ | 3" | 8 1/2" | 11 1/2" | Lever | Pop Safety | 0000000 | 000000 |
Fast-Acting Pressure-Relief Valves for Air and Inert Gas
![](/prerenderstable/mvPRE/contents/gfx/imagecache/477/4772k801p1-c03a-digital@halfx_636856103040755136.png?ver=imagenotfound)
![](/prerenderstable/mvPRE/contents/gfx/imagecache/470/4701k82p1-c03a-digital@halfx_637091681440035615.png?ver=imagenotfound)
![](/prerenderstable/mvPRE/contents/gfx/imagecache/902/9024k313p1-c03a-digital@halfx_637091663021986308.png?ver=imagenotfound)
With
Test Ring
- For Use With: Air, Inert Gas
- Temperature Range: -30° to 400° F
These valves spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. They have a vented relief port to exhaust discharge directly.
For technical drawings and 3-D models, click on a part number.
Inlet | |||||||||
---|---|---|---|---|---|---|---|---|---|
Pipe Size | Location | Maximum Pressure, psi | Relief Port Location | Overall Ht. | Test Mechanism | Valve Type | Choose a Set Pressure, psi | Each | |
NPT Male Inlet and Relief Vent | |||||||||
Brass Body and Seal | |||||||||
1/8 | Bottom | 100 | Side | 1 3/4" | __ | Pop Safety | 000000 | 000000 | |
1/4 | Bottom | 200 | Top | 3 1/8" | Lever | Pop Safety | 0000000 | 00000 | |
1/4 | Bottom | 300 | Side | 2 1/2" | __ | Pop Safety | 000000 | 00000 | |
1/4 | Bottom | 300 | Side | 3 1/8" | Ring | Pop Safety | 0000000 | 00000 | |
3/8 | Bottom | 200 | Top | 3 1/8" | Lever | Pop Safety | 0000000 | 00000 | |
3/8 | Bottom | 300 | Side | 2 1/2" | __ | Pop Safety | 000000 | 00000 | |
3/8 | Bottom | 300 | Side | 3 1/8" | Ring | Pop Safety | 0000000 | 00000 | |
1/2 | Bottom | 200 | Top | 3 1/8" | Lever | Pop Safety | 0000000 | 00000 | |
1/2 | Bottom | 300 | Side | 2 5/8" | __ | Pop Safety | 000000 | 00000 | |
1/2 | Bottom | 300 | Side | 3 3/4" | Ring | Pop Safety | 0000000 | 00000 | |
3/4 | Bottom | 300 | Side | 5 7/16" | Ring | Pop Safety | 0000000 | 000000 | |
1 | Bottom | 300 | Side | 5 3/4" | Ring | Pop Safety | 0000000 | 000000 |
Heat-Activated Threaded Pressure-Relief Discs
![](/prerenderstable/mvPRE/contents/gfx/imagecache/276/2764n16-@halfx_637575266861751907.png?ver=imagenotfound)
Also known as fusible plugs, these discs have a metal core that melts at a set temperature to exhaust discharge directly and allow unrestricted flow. Install these one-time-use discs in pipelines and tanks.
Exceeding the maximum operating temperature decreases service life and may cause the disc to open below its melting temperature. These discs should not be used in a system with an operating pressure greater than 500 psi.
Inlet | |||||||||
---|---|---|---|---|---|---|---|---|---|
Pipe Size | Location | Relief Port Location | Max. Pressure, psi | Max. Operating Temperature, °F | Overall Ht. | Disc Material | Valve Type | Each | |
NPT Male Inlet and Relief Vent | |||||||||
Brass Body—165° F Melting Temperature | |||||||||
1/4 | Bottom | Top | 500 | 100° | 3/4" | Bismuth, Cadmium, Lead, Tin | Rupture Disc | 0000000 | 000000 |
3/8 | Bottom | Top | 500 | 100° | 3/4" | Bismuth, Cadmium, Lead, Tin | Rupture Disc | 0000000 | 00000 |
1/2 | Bottom | Top | 500 | 100° | 7/8" | Bismuth, Cadmium, Lead, Tin | Rupture Disc | 0000000 | 00000 |
Brass Body—212° F Melting Temperature | |||||||||
1/4 | Bottom | Top | 500 | 150° | 3/4" | Bismuth, Lead, Tin | Rupture Disc | 0000000 | 00000 |
3/8 | Bottom | Top | 500 | 150° | 3/4" | Bismuth, Lead, Tin | Rupture Disc | 0000000 | 00000 |
1/2 | Bottom | Top | 500 | 150° | 7/8" | Bismuth, Lead, Tin | Rupture Disc | 0000000 | 00000 |