National Standard Check Valve

Size Range: DN25-DN400

Material: Stainless Steel, Carbon steel

Connection Options: Flange

Working Pressure: 1.6 ~ 25MPa

Working Temperature:-29°C to 550°C

Manufacturing Method: Carbon steel

Applicable Medium:Oil, Gas, Water

Product Overview

The National Standard Check Valve is a robust, one-way flow control valve that prevents backflow in piping systems. Designed according to national standards, this valve is essential for protecting equipment and ensuring unidirectional flow in various industrial applications. It operates automatically, using the fluid pressure to open or close the valve, thus eliminating the need for manual control.

Product Features

Reliable Backflow Prevention: Ensures unidirectional flow to protect pumps, compressors, and other sensitive equipment.

Automatic Operation: Opens and closes based on fluid pressure, eliminating manual intervention.

Durable Construction: Built from high-quality materials for long-lasting performance, even under demanding conditions.

Multiple Connection Options: Available with various connection types to suit different piping systems.

Temperature and Pressure Resilience: Designed to withstand a broad range of pressures and temperatures, making it suitable for versatile applications.

Compliant with National Standards: Adheres to national standards for consistency, safety, and quality in industrial environments.

Specification Parameters

Performance Parameters

No.	Project Name	PN16	PN25	PN40	PN64	PN100	PN160
1	Nominal Pressure PN (MPa)	1.6	2.5	4.0	6.4	10	16
2	Shell Test Pressure (MPa)	2.4	3.75	6.0	9.6	16	24
3	High-Pressure Sealing Test (MPa)	1.76	2.75	4.4	7.04	11	17.6
4	Maximum Working Pressure (MPa)	≤1.6	≤2.5	≤4.0	≤6.4	≤10	≤16

Main Components Material

Part Name	Material (PN16)	Material (PN25)	Material (PN40–160)
Body	WCB	15CrMo	20CrMoV
Valve Cover	WCB	15CrMo	20CrMoV
Disc	A105	15CrMo	20CrMoV
Sealing Face	20Cr13	STL	STL
Shaft Pin	20Cr13	35CrMoV	35CrMoV
Gasket	304 + Flexible graphite	304 + Flexible graphite	304 + Flexible graphite
Bolt	35CrMoA	35CrMoA	35CrMoA
Nut	30CrMo	30CrMo	30CrMo
Applicable Temperature	-29°C to 425°C	-29°C to 540°C	-29°C to 560°C
Suitable Medium	Water, steam, oil, etc.	Water, steam, oil, etc.	Water, steam, oil, etc.

Main External and Connection Dimensions

PN (MPa)	DN (mm)	L (mm)	D (mm)	D1 (mm)	D2 (mm)	b–f (mm)	Z–φd (mm)	D6 (mm)	H (mm)	Weight (kg)
1.6	50	230	160	125	100	16–2	4–φ18	/	160	22
	65	290	180	145	120	18–3	4–φ18	/	177	26
	80	310	195	160	135	20–3	8–φ18	/	187	33
	100	350	215	180	155	20–3	8–φ18	/	202	39
	125	400	245	210	185	22–3	8–φ18	/	227	57
	150	480	280	240	210	24–3	8–φ23	/	263	80
	200	550	335	295	265	26–3	12–φ23	/	293	95
	250	650	405	355	320	30–3	12–φ25	/	330	175
	300	750	460	410	375	30–4	12–φ25	/	382	260
	350	850	520	470	435	34–4	16–φ25	/	430	360
	400	950	580	525	485	36–4	16–φ30	/	480	496
	500	1150	705	650	608	44–4	20–φ34	/	560	588
2.5	50	230	160	125	100	20–3	4–φ18	/	177	22
	65	290	180	145	120	22–3	8–φ18	/	192	30
	80	310	195	160	135	22–3	8–φ18	/	192	35
	100	350	230	190	160	24–3	8–φ23	/	217	52
	125	400	245	220	188	28–3	8–φ25	/	250	73
	150	480	300	250	218	30–3	8–φ30	/	270	103
	200	550	360	310	276	34–3	12–φ25	/	350	135
	250	650	425	370	332	36–3	12–φ30	/	410	196
	300	750	485	430	390	40–4	16–φ30	/	430	285
	350	850	555	490	448	44–4	16–φ34	/	450	388
	400	950	620	550	505	48–4	16–φ34	/	560	496
	500	1150	730	660	610	52–4	20–φ41	/	618	641

PN (MPa)	DN (mm)	L	D	D1	D2	D6	b–f	F2	Z–φd	H	Weight (kg)
4.0	50	230	160	125	105	88	20–3	4.5	4–φ18	177	22
	65	290	180	145	130	110	22–3	4.5	4–φ18	192	30
	80	310	195	160	140	121	22–3	4.5	8–φ18	192	34
	100	350	230	190	168	150	24–3	4.5	8–φ23	217	52
	125	400	270	220	202	176	28–3	4.5	8–φ25	259	73
	150	480	300	250	240	204	30–3	4.5	8–φ25	270	103
	200	550	375	320	300	260	38–3	4.5	12–φ30	340	212
	250	650	445	385	352	313	42–3	4.5	12–φ34	401	297
	300	750	510	450	412	364	46–4	4.5	16–φ34	423	362
	350	850	570	510	475	422	52–4	5	16–φ34	460	450
	400	950	655	585	525	474	58–4	5	16–φ41	490	585
	500	1150	755	670	612	576	62–4	5	20–φ48	618	641
PN (MPa)	DN (mm)	L	D	D1	D2	D6	b–f	F2	Z–φd	H	Weight (kg)
6.4	50	300	175	135	105	88	26–3	4	4–φ23	192	30
	65	340	200	160	130	110	28–3	4	8–φ23	207	41
	80	380	210	170	140	121	30–3	4.5	8–φ23	207	48
	100	430	250	200	168	150	32–3	4.5	8–φ25	235	72
	125	500	295	240	202	176	36–3	4.5	8–φ30	265	105
	150	580	340	280	240	204	38–3	4.5	8–φ34	297	155
	200	650	405	345	300	260	44–3	4.5	12–φ34	357	217
	250	775	470	400	352	313	48–3	4.5	12–φ41	405	341
	300	900	530	460	412	364	54–4	4.5	16–φ41	465	472
	350	1025	595	525	475	422	60–4	5	16–φ41	514	627
	400	1150	675	585	535	474	65–4	5	16–φ48	568	882
PN (MPa)	DN (mm)	L	D	D1	D2	D6	b–f	F2	Z–φd	H	Weight (kg)
10.0	50	300	195	145	112	88	28–3	4	4–φ25	192	41
	65	340	220	170	138	110	32–3	4	8–φ25	207	48
	80	380	230	180	148	121	34–3	4.5	8–φ30	235	72
	100	430	265	210	172	150	38–3	4.5	8–φ30	265	108
	125	500	315	250	210	175	42–3	4.5	8–φ34	310	130
	150	580	350	290	250	204	46–3	4.5	12–φ34	360	217
	200	650	450	360	312	260	54–3	4.5	12–φ41	420	341
	250	775	500	430	382	313	60–3	4.5	12–φ41	480	472
	300	900	585	500	442	364	70–4	5	16–φ48	520	620
	350	1025	665	560	498	422	76–4	5	16–φ54	584	830
	400	1150	715	620	558	474	80–4	5	16–φ54	625	1060
PN (MPa)	DN (mm)	L	D	D1	D2	D6	b–f	F2	Z–φd	H	Weight (kg)
16.0	50	300	215	165	132	88	36–3	4	4–φ28	251	49
	65	340	245	190	152	110	44–3	4	8–φ30	282	58
	80	380	290	225	168	121	46–3	4.5	8–φ30	324	110
	100	430	305	240	200	150	48–3	4.5	8–φ34	356	162
	125	500	355	285	238	176	60–3	4.5	8–φ41	393	214
	150	580	390	318	270	204	66–3	4.5	12–φ41	430	267
	200	650	470	385	345	260	78–3	4.5	12–φ48	476	443
	250	800	580	485	425	313	88–3	4.5	12–φ54	514	610
	300	950	685	570	510	364	104–4	4.5	16–φ54	587	685
PN (MPa)	DN (mm)	L	D	D1	D2	D6	b–f	F2	Z–φd	H	Weight (kg)
25.0	50	368	210	160	128	70	40–3	5	8–φ25	310	63
	65	419	220	203	165	97	48–3	5	8–φ30	348	78
	80	470	290	230	190	116	54–3	5	8–φ34	385	140
	100	546	330	292	245	138	66–3	6	12–φ41	406	210
	125	673	385	318	270	170	76–3	6	12–φ41	534	280
	150	780	460	385	306	190	82–3	6	12–φ55	580	347
	200	832	535	440	380	245	92–3	6	12–φ51	318	575
	250	991	670	572	508	319	110–3	6	16–φ55	673	790

Specification Applications

Water Treatment: Used to maintain proper flow direction and prevent contamination in water distribution systems.

Petrochemical Industry: Prevents backflow in pipelines carrying oil, gas, and other hydrocarbons.

Power Generation: Ensures safe and unidirectional flow in high-pressure steam and cooling systems.

Industrial Manufacturing: Protects equipment in fluid transfer and process systems.

HVAC Systems: Prevents backflow in heating, ventilation, and air conditioning systems.

Your Trusted Control Valve Manufacturer & Supplier

National Standard Check Valve

Product Overview

Product Features

Specification Parameters

Performance Parameters

Main Components Material

Main External and Connection Dimensions

Specification Applications

Features

Resources

Links

Contact info