Steam Relief Valves | McMaster-Carr

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EAR99

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69 Products

ASME-Code Fast-Acting Pressure-Relief Valves for Steam

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.

NPT Male Inlet and NPT Female Relief Port


Valve With Test Lever	Valve With Swivel Test Lever

EPM Rubber Seal—EPM rubber seals provide better leak protection than brass seals.

Swivel—Swivel test levers rotate 360° around the valve for use in areas with limited clearance.

Inlet			Relief
Pipe Size	Location	Max. Pressure, psi	Port Pipe Size	Port Location	Shape	Overall Ht.	For Use With	Temp. Range, ° F	Test Mechanism	Test Lever Type	Valve Type	Certification	Choose a Set Pressure, psi		Each







			Bronze Body—Brass Seal

			1/2	Bottom	250	3/4	Side	90° Elbow	6 1/2"	Steam	-60 to 400	Lever	—	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4700K23	0000000


			1/2	Bottom	250	3/4	Side	90° Elbow	7 5/16"	Steam	-60 to 400	Lever	Swivel	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4755K11	000000
			3/4	Bottom	250	3/4	Side	90° Elbow	7 5/16"	Steam	-60 to 400	Lever	Swivel	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4755K12	000000
			3/4	Bottom	250	1	Side	90° Elbow	7 1/2"	Steam	-60 to 400	Lever	—	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4700K24	000000
			1	Bottom	250	1	Side	90° Elbow	7 5/8"	Steam	-60 to 400	Lever	Swivel	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4755K13	000000
			1	Bottom	250	1 1/4	Side	90° Elbow	8 1/2"	Steam	-60 to 400	Lever	—	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4700K25	000000
			1 1/4	Bottom	250	1 1/2	Side	90° Elbow	9 5/8"	Steam	-60 to 400	Lever	—	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4700K26	000000
			1 1/2	Bottom	250	1 1/2	Side	90° Elbow	9 5/8"	Steam	-60 to 400	Lever	Swivel	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4755K15	000000
			1 1/2	Bottom	250	2	Side	90° Elbow	10 5/8"	Steam	-60 to 400	Lever	—	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4700K27	000000
			2	Bottom	250	2 1/2	Side	90° Elbow	13 5/8"	Steam	-60 to 400	Lever	—	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	4700K28	000000




					Bronze Body—EPM Rubber Seal

					1/2	Bottom	250	3/4	Side	90° Elbow	6 1/2"	Steam	-60 to 400	Lever	—	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	6187T17	000000


					3/4	Bottom	250	1	Side	90° Elbow	7 1/2"	Steam	-60 to 400	Lever	—	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	6187T18	000000
					1	Bottom	250	1 1/4	Side	90° Elbow	8 1/2"	Steam	-60 to 400	Lever	—	Pop Safety	ASME BPVC.I	15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250	6187T19	000000

ASME-Code Fast-Acting Pressure-Relief Valves for Low-Pressure Steam

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.

Straight

Vent Relief Port—Vented relief ports exhaust discharge directly.

	Inlet					Relief
	Pipe Size	Thread Type	Gender	Location	Max. Pressure, psi	Port	Port Location	Steam Flow Cap., lb/hr	Set Pressure, psi	Overall Ht.	Test Mechanism	Valve Type	For Use With	Certification	Max. Temp., ° F		Each
Bronze Body—EPDM Seal



		3/4	NPT	Male	Bottom	15	Vent	Top	410	15	2 7/8"	Lever	Pop Safety	Steam	ASME BPVC.IV	250	4699K35	000000

90° Elbow

Threaded—Threaded relief ports can be attached to a drain line for remote discharge.

	Inlet					Relief
	Pipe Size	Thread Type	Gender	Location	Max. Pressure, psi	Port Pipe Size	Port	Port Fitting Connection	Port Thread Type	Port Gender	Port Location	Steam Flow Cap., lb/hr	Set Pressure, psi	Overall Ht.	Test Mechanism	Valve Type	For Use With	Certification	Max. Temp., ° F		Each
Bronze Body—PTFE-Coated EPDM Seal



		3/4	NPT	Male	Bottom	15	3/4	Pipe	Threaded	NPT	Female	Side	470	15	3 13/16"	Lever	Pop Safety	Steam	ASME BPVC.IV	250	4699K45	0000000


		1	NPT	Male	Bottom	15	1	Pipe	Threaded	NPT	Female	Side	640	15	4"	Lever	Pop Safety	Steam	ASME BPVC.IV	250	4699K46	000000
		1 1/4	NPT	Male	Bottom	15	1 1/2	Pipe	Threaded	NPT	Female	Side	1,200	15	4 1/2"	Lever	Pop Safety	Steam	ASME BPVC.IV	250	4699K55	000000
		1 1/2	NPT	Male	Bottom	15	2	Pipe	Threaded	NPT	Female	Side	1,900	15	5 1/4"	Lever	Pop Safety	Steam	ASME BPVC.IV	250	4699K65	000000
		2	NPT	Male	Bottom	15	2	Pipe	Threaded	NPT	Female	Side	2,500	15	6 9/16"	Lever	Pop Safety	Steam	ASME BPVC.IV	250	4699K7	000000
		2 1/2	NPT	Male	Bottom	15	2 1/2	Pipe	Threaded	NPT	Female	Side	3,520	15	8 1/8"	Lever	Pop Safety	Steam	ASME BPVC.IV	250	4699K8	000000
		3	NPT	Male	Bottom	15	3	Pipe	Threaded	NPT	Female	Side	4,100	15	9 1/16"	Lever	Pop Safety	Steam	ASME BPVC.IV	250	4699K9	000000

Fast-Acting Pressure-Relief Valves for Ultra-Low-Pressure Steam

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.

Straight

Vent Relief Port—Vented relief ports exhaust discharge directly.

	Inlet				Relief
	Pipe Size	Thread Type	Gender	Location	Port	Port Location	Overall Ht.	Test Mechanism	Valve Type	For Use With	Max. Temp., ° F	Choose a Set Pressure, psi		Each
Bronze Body—EPDM Seal



		3/4	NPT	Male	Bottom	Vent	Top	2 7/8"	Lever	Pop Safety	Steam	250	5, 6, 8, 10, 12	4699K11	000000

90° Elbow

Threaded—Threaded relief ports can be attached to a drain line for remote discharge.

	Inlet				Relief
	Pipe Size	Thread Type	Gender	Location	Port Pipe Size	Port	Port Fitting Connection	Port Thread Type	Port Gender	Port Location	Overall Ht.	Test Mechanism	Valve Type	For Use With	Max. Temp., ° F	Choose a Set Pressure, psi		Each
Bronze Body—EPDM Seal



		3/4	NPT	Male	Bottom	3/4	Pipe	Threaded	NPT	Female	Side	3 13/16"	Lever	Pop Safety	Steam	250	5, 6, 8, 10, 12	4699K12	0000000


		1	NPT	Male	Bottom	1	Pipe	Threaded	NPT	Female	Side	4"	Lever	Pop Safety	Steam	250	5, 6, 8, 10, 12	4699K13	000000

Corrosion-Resistant Pressure-Regulating Valves for Steam

Regulate steam pressure in wet environments and harsh conditions with these valves that have a 316 stainless steel body for exceptional corrosion resistance. They automatically reduce a high, variable inlet pressure to a lower, stable outlet pressure. Adjust the outlet pressure within the range.

	Inlet			Outlet
	Pipe Size	Location	Max. Pressure, psi	Pipe Size	Location	Pressure Adjustment Method	End-to-End Lg.	For Use With	Temp. Range, ° F	Choose an Outlet Pressure, psi		Each
NPT Female







				316 Stainless Steel Body—316 Stainless Steel Diaphragm and PTFE Seal

				1/2	Side	400	1/2	Side	Screw	4 1/2"	Steam	-40 to 450	2 to 30, 10 to 50, 30 to 125, 50 to 150	8099K41	000000000


				3/4	Side	400	3/4	Side	Screw	5 1/8"	Steam	-40 to 450	2 to 20, 10 to 35, 30 to 75, 50 to 110, 105 to 150	8099K51	00000000
				1	Side	400	1	Side	Screw	5 7/8"	Steam	-40 to 450	2 to 20, 10 to 45, 20 to 60, 55 to 100, 90 to 150	8099K61	00000000

Pressure-Regulating Valves for Steam

Automatically reduce a high, variable inlet pressure in your steam system to a lower, stable outlet pressure. Adjust the outlet pressure within the range. These valves have a cast iron body that absorbs vibration from pressure changes to reduce wear and noise in your pipeline.

Internal Strainer—Internal strainers trap debris.

	Valves												Repair Kits
	Inlet			Outlet
	Pipe Size	Location	Max. Pressure, psi	Pipe Size	Location	Pressure Adjustment Method	End-to-End Lg.	For Use With	Temp. Range, ° F	Choose an Outlet Pressure, psi		Each		Each
NPT Female







				Cast Iron Body—Bronze Diaphragm and 420 Stainless Steel Seal

				1/2	Side	250	1/2	Side	Screw	3 5/8"	Steam	-20 to 400	0 to 10, 10 to 50, 40 to 100, 100 to 200	9796K38	0000000	9796K96	000000


				3/4	Side	250	3/4	Side	Screw	3 5/8"	Steam	-20 to 400	0 to 10, 10 to 50, 40 to 100, 100 to 200	9796K39	000000	9796K96	00000
				1	Side	250	1	Side	Screw	4 1/2"	Steam	-20 to 400	0 to 10, 10 to 30, 30 to 50, 40 to 85	9796K91	000000	9796K97	000000
				1 1/4	Side	250	1 1/4	Side	Screw	4 1/2"	Steam	-20 to 400	0 to 10, 10 to 30, 30 to 50, 40 to 85	9796K92	000000	9796K97	000000
				1 1/2	Side	250	1 1/2	Side	Screw	6 1/2"	Steam	-20 to 400	0 to 10, 10 to 30, 30 to 50, 40 to 85	9796K93	000000	9796K99	000000
				2	Side	250	2	Side	Screw	6 1/2"	Steam	-20 to 400	0 to 10, 10 to 30, 30 to 50, 40 to 85	9796K94	000000	9796K99	000000




						Cast Iron Body—Bronze Diaphragm and PTFE Seal with Internal Strainer

						1/4	Side	150	1/4	Side	Screw	3"	Steam	-20 to 400	2 to 25, 20 to 60, 30 to 100	4674K61	000000	———	0


						3/8	Side	150	3/8	Side	Screw	3 7/8"	Steam	-20 to 400	2 to 30, 20 to 70, 90 to 150	4674K62	000000	———	0
						1/2	Side	150	1/2	Side	Screw	4 1/2"	Steam	-20 to 400	2 to 30, 10 to 50, 30 to 125, 50 to 150	4674K63	000000	4674K91	000000
						3/4	Side	150	3/4	Side	Screw	5 1/8"	Steam	-20 to 400	2 to 20, 10 to 35, 30 to 75, 50 to 110, 105 to 150	4674K64	000000	4674K92	000000
						1	Side	150	1	Side	Screw	5 7/8"	Steam	-20 to 400	2 to 20, 10 to 45, 20 to 60, 55 to 100, 90 to 150	4674K65	000000	4674K93	000000
						1 1/4	Side	150	1 1/4	Side	Screw	6 3/4"	Steam	-20 to 400	2 to 15, 10 to 30, 20 to 50, 45 to 100, 90 to 150	4674K66	000000	4674K94	000000
						1 1/2	Side	150	1 1/2	Side	Screw	6 3/4"	Steam	-20 to 400	2 to 15, 10 to 30, 20 to 50, 45 to 100, 90 to 150	4674K67	000000	4674K94	000000
						2	Side	150	2	Side	Screw	9 1/4"	Steam	-20 to 400	2 to 20, 10 to 60, 20 to 100, 90 to 150	4674K68	00000000	4674K95	000000

Long-Life Pressure-Regulating Valves for Steam

For a longer service life than cast iron valves, these have a durable bronze body. All automatically reduce a high, variable inlet pressure to a lower, stable outlet pressure. Adjust the outlet pressure within the range. Valves have an internal strainer to trap debris.

	Inlet			Outlet
	Pipe Size	Location	Max. Pressure, psi	Pipe Size	Location	Pressure Adjustment Method	End-to-End Lg.	For Use With	Temp. Range, ° F	Choose an Outlet Pressure, psi		Each
NPT Female







				Bronze Body—Bronze Diaphragm and PTFE Seal with Internal Strainer

				1/4	Side	250	1/4	Side	Screw	3"	Steam	-20 to 400	2 to 25, 20 to 60	47345K31	0000000


				3/8	Side	250	3/8	Side	Screw	3 7/8"	Steam	-20 to 400	2 to 30, 20 to 70, 40 to 110, 90 to 150	47345K32	000000
				1/2	Side	250	1/2	Side	Screw	4 1/2"	Steam	-20 to 400	2 to 30, 10 to 50, 30 to 125, 50 to 150	47345K33	000000
				3/4	Side	250	3/4	Side	Screw	5 1/8"	Steam	-20 to 400	2 to 20, 10 to 35, 30 to 75, 50 to 110, 105 to 150	47345K34	000000
				1	Side	250	1	Side	Screw	5 7/8"	Steam	-20 to 400	2 to 20, 10 to 45, 20 to 60, 55 to 100, 90 to 150	47345K35	000000
				1 1/4	Side	250	1 1/4	Side	Screw	6 3/4"	Steam	-20 to 400	2 to 15, 10 to 30, 20 to 50, 45 to 100, 90 to 150	47345K36	00000000
				1 1/2	Side	250	1 1/2	Side	Screw	6 3/4"	Steam	-20 to 400	2 to 15, 10 to 30, 20 to 50, 45 to 100, 90 to 150	47345K37	00000000
				2	Side	250	2	Side	Screw	9 1/4"	Steam	-20 to 400	2 to 20, 10 to 60, 20 to 100, 90 to 150	47345K38	00000000

High-Accuracy Pressure-Regulating Valves for Steam

Control steam line pressure with ±1 psi accuracy. These valves automatically reduce a high, variable inlet pressure to a lower, stable outlet pressure. Adjust the outlet pressure within the range. Valves have a cast iron body that absorbs vibration from pressure changes to reduce wear and noise in your pipeline. They meet ANSI/FCI 70-2 Class IV for tight shut-off (max. leakage rate of 0.01%). Install _1/4 NPT male pipe (not included) between the control valve and your downstream steam line.

Repair Kits—Repair kits (sold separately) include replacement seals, diaphragm, spring, and spring assembly.

	Valves												Repair Kits
	Inlet			Outlet
	Pipe Size	Location	Max. Pressure, psi	Pipe Size	Location	Pressure Adjustment Method	For Use With	Temp. Range, ° F	Specs. Met	Choose an Outlet Pressure, psi		Each		Each
NPT Female







				Cast Iron Body—301 Stainless Steel Diaphragm and 420 Stainless Steel Seal

				1/2	Side	250	1/2	Side	Screw	Steam	40 to 450	ANSI/FCI 70-2 Class IV	3 to 20, 5 to 50, 10 to 100, 20 to 150	9792K19	000000000	9792K32	0000000


				3/4	Side	250	3/4	Side	Screw	Steam	40 to 450	ANSI/FCI 70-2 Class IV	3 to 20, 5 to 50, 10 to 100, 20 to 150	9792K21	00000000	9792K33	000000
				1	Side	250	1	Side	Screw	Steam	40 to 450	ANSI/FCI 70-2 Class IV	3 to 20, 5 to 50, 10 to 100, 20 to 150	9792K23	00000000	9792K34	000000
				1 1/4	Side	250	1 1/4	Side	Screw	Steam	40 to 450	ANSI/FCI 70-2 Class IV	3 to 20, 5 to 50, 10 to 100, 20 to 150	9792K25	00000000	9792K35	000000
				1 1/2	Side	250	1 1/2	Side	Screw	Steam	40 to 450	ANSI/FCI 70-2 Class IV	3 to 20, 5 to 50, 10 to 100, 20 to 150	9792K27	00000000	9792K36	000000
				2	Side	250	2	Side	Screw	Steam	40 to 450	ANSI/FCI 70-2 Class IV	3 to 20, 5 to 50, 10 to 100, 20 to 150	9792K29	00000000	9792K37	00000000