Name: China Customized Closed Bonnet Full Lift Safety Valve Manufacturers Suppliers Factory - Starry
Brand: Starry
SKU: 314858589

Description

Technical Parameters

Wenzhou Starry Valve Co., Ltd. is one of the most reliable manufacturers and suppliers of closed bonnet full lift safety valve in China. We are committed to providing high quality customized valves with low price. If you're going to buy bulk durable closed bonnet full lift safety valve, welcome to get quotation from our factory.

Size Range	3/4" ~ 16"
Pressure Rating	PN16 ~ PN100
Temperature Range	Carbon Steel: -20℃~350℃; Stainless Steel: -40℃~450℃; high-temp custom up to 550℃
Connection Type	Flanged
Material	Carbon Steel / Alloy Steel / Stainless Steel
Operation	Spring-Loaded, Closed Bonnet, Full Lift
Suitable Medium	Water, Steam, Air, Oil, Natural Gas etc.; Stainless Steel for Weakly Corrosive Media; Closed Structure for Toxic / Flammable Media

Features

1.Leak-Tight Closed-Bonnet No-Lever Structure

A42Y adopts fully-enclosed bonnet design with no manual test lever. All relief medium is guided to outlet discharge piping; no volatile or harmful medium escapes to atmosphere. Prevent dust and moisture entering internal spring components. Simple compact construction for locations where manual on-site lifting test is not required.

2.Full-lift Pop-Action with Back-Blow Disc

Built-in back-blow-disc assembly. Once reaching set-pressure, valve pops open instantly with lift ≥1/4 nozzle diameter for large-capacity relief. Adjustable nozzle ring allows blow-down tuning. Discharge performance conforms to API-520 capacity criteria, excellent for compressible gas and hydrocarbon service.

3.Stellite Hard-Alloy Overlay Sealing Pair

Nozzle and disc seating face hard-faced with Stellite cobalt-base alloy. High resistance against erosion and wear under cyclic relief operation. Seat tightness meets API-527 leakage standard, minimize seat-seepage risk for hydrocarbon and volatile-gas application.

4.Conventional Spring-Loaded Mechanical Performance

Pure spring-driven design without external power source. Set-pressure adjustable on-site. Automatic opening upon over-pressure; tight re-seating when pressure drops to blow-down range. Important note: this is non-bellows conventional type. Fluctuating superimposed back-pressure will affect set-pressure and re-seating performance. Select WA42Y bellows-balanced version for variable back-pressure conditions.

5.Multi-Material Options for Diverse Working Conditions

WCB carbon steel for general-purpose gas-hydrocarbon service; CF8 / CF8M stainless steel for corrosive fluid. NACE-MR0175 wetted trim can be specially ordered for wet-H₂S sour-service. Available for GB PN or ASME B16.5 pound-grade flange.

Typical Application Equipment

- Petrochemical pressure vessels, hydrocarbon storage tanks and separators

- LPG, petroleum-gas and volatile-medium process piping system

- Industrial pressure equipment requiring closed discharge without manual-lever test

- Chemical plant over-pressure protection for compressible gas medium

Working Principle & Application Notes

Closed bonnet Full lift Safety Valve is closed-bonnet full-lift spring-loaded safety valve without manual lever. Under normal operating pressure, spring force holds disc firmly against nozzle seat. When system pressure rises to set-pressure, medium thrust overcomes spring preload; back-blow-disc generates extra lifting force and valve pops fully open for large-capacity decompression. When pressure falls to blow-down reset value, spring pushes disc back into seating position for tight shut-off. Non-bellows conventional construction, variable back-pressure will cause set-pressure drift; choose WA42Y bellows-balanced model for fluctuating back-pressure.Closed bonnet Full lift Safety Valve not suitable for H₂S-containing sour-service unless NACE-compliant material upgrade is specified. Provide set-pressure, operating temperature, medium property and required relief-capacity for correct sizing before order.

A42 Series Models
A42Y-16C	A42Y-16P	A42Y-16R	A42Y-40	A42Y-40P
A42Y-40R	A42Y-100	A42Y-100P	A42Y-100R	KA42Y-16
DA42Y-16(P)	A42Y-25	A42Y-25P	A42Y-25R	A21Y-16R
DA42Y-25(P)	A42Y-64	A42Y-64P	A42Y-64R	A42Y-64
KA42Y-64	KA42Y-100	DA42Y-100(P)	DA42Y-25(P)	DA42Y-64(P)

	Part Name	A42Y-C/KA42Y-C	A42Y-P/KA42Y-P	A42Y-R	DA42Y-P
1	Body	2Cr13/1Cr18Ni9Ti	ZG1Cr18Ni9Ti	ZG1Cr18Ni12Mo2Ti	ZG1Cr18Ni9Ti
2	Seat	WCB	ZG1Cr18Ni9Ti	ZG1Cr18Ni12Mo2Ti	LCB/ZG1Cr18Ni9Ti
3	Adjusting Ring	2Cr13/1Cr18Ni9Ti	1Cr18Ni9Ti	1Cr18Ni12Mo2Ti	1Cr18Ni9Ti
4	Disc Holder	2Cr13/1Cr18Ni9Ti	1Cr18Ni9Ti	1Cr18Ni12Mo2Ti	1Cr18Ni9Ti
5	Disc	2Cr13/1Cr18Ni9Ti	1Cr18Ni9Ti	1Cr18Ni12Mo2Ti	1Cr18Ni9Ti
6	Guide sleeve	2Cr13/1Cr18Ni9Ti	1Cr18Ni9Ti	1Cr18Ni12Mo2Ti	1Cr18Ni9Ti
7	Bonnet	ZG230-450	ZG230-450	ZG230-450	ZG1Cr18Ni9Ti
8	Spring	50CrVA	50CrVA, Teflon Coated	50CrVA, Teflon Coated	50CrVA
9	Stem	2Cr13	1Cr18Ni9Ti/1Cr18Ni12Mo2Ti	1Cr18Ni9Ti/1Cr18Ni12Mo2Ti	1Cr18Ni9Ti
10	Adjusting Bolt	45	2Cr13	2Cr13	2Cr13
11	Cap	ZG200-400	ZG200-400	ZG200-400	ZG230-450
	Sealing surface of material	Co-based Hard Alloy Overlay

Closed bonnet Full Lift Safety Valve (mm)

Dimensions (mm)
Type	DN	do	D	K	g	g₁	b	f	f₁	Z-φd	DN¹	D₁	k₁	g³	g²	b₁	f'	f'₁	Z¹-φd¹	L	L₁	≈H
A42Y-16C A42Y-16P A42Y-16R KA42Y-16C DA42Y-16C(P)	20	15	105	75	/	55	16	2	/	4-14	25	115	85	/	65	16	2	/	4-14	110	95	378
	25	16	115	85	/	65	16	2	/	4-14	32	140	100	/	78	18	2	/	4-18	110	95	378
	32	20	140	100	/	78	18	2	/	4-18	40	150	110	/	85	18	3	/	4-18	115	100	378
	40	25	150	110	/	85	18	3	/	4-18	50	165	125	/	100	20	3	/	4-18	120	110	406
	50	32	165	125	/	100	20	3	/	4-18	65	185	145	/	120	20	3	/	4-18	135	120	450
	65	40	185	145	/	120	20	3	/	4-18	80	200	160	/	135	20	3	/	8-18	160	140	520
	80	50	200	160	/	135	20	3	/	8-18	100	220	180	/	155	22	3	/	8-18	170	135	525
	100	65	220	180	/	155	22	3	/	8-18	125	250	210	/	185	22	3	/	8-18	195	175	690
	125	80	250	210	/	185	22	3	/	8-18	150	285	240	/	210	24	3	/	8-23	210	190	780
	150	100	285	240	/	210	24	3	/	8-23	175	310	270	/	240	26	3	/	8-23	255	230	838
	200	125	340	295	/	265	26	3	/	12-23	250	405	355	/	320	30	3	/	12-26	300	260	992
	250	150	405	355	/	320	30	3	/	12-26	300	460	410	/	375	30	4	/	12-26	350	320	1266
	300	220	460	410	/	375	30	4	/	12-26	400	580	525	/	485	36	4	/	16-30	370	350	1283
	350	250	520	470	/	435	34	4	/	16-26	500	715	650	/	608	44	4	/	20-34	500	450	1520
	400	280	580	525	/	485	36	4	/	16-30	500	715	650	/	608	44	4	/	20-34	500	450	1530
A42Y-25C A42Y-25P A42Y-25R KA42Y-25C DA42Y-25(P)	20	15	105	75	/	55	16	2	/	4-14	25	115	85	/	65	16	2	/	4-14	110	95	378
	25	16	115	85	/	65	16	2	/	4-14	32	140	100	/	78	18	2	/	4-18	110	95	378
	32	20	140	100	/	78	18	2	/	4-18	40	150	110	/	85	18	3	/	4-18	115	100	378
	40	25	150	110	/	85	18	3	/	4-18	50	165	125	/	100	20	3	/	4-18	120	110	406
	50	32	165	125	/	100	20	3	/	4-18	65	185	145	/	120	20	3	/	4-18	135	120	450
	65	40	185	145	/	120	22	3	/	8-18	80	200	160	/	135	20	3	/	8-18	160	140	520
	80	50	200	160	/	135	22	3	/	8-18	100	220	180	/	155	22	3	/	8-18	170	135	525
	100	65	230	190	/	160	24	3	/	8-23	125	250	210	/	185	22	3	/	8-18	195	175	690
	125	80	270	220	/	188	28	3	/	8-26	150	285	240	/	210	24	3	/	8-23	210	190	780
	150	100	300	250	/	218	30	3	/	8-26	175	310	270	/	240	26	3	/	8-23	255	230	838
	200	125	360	310	/	278	34	3	/	12-26	250	405	355	/	320	30	3	/	12-26	300	260	992
	250	150	425	370	/	332	36	3	/	12-30	300	460	410	/	375	30	4	/	12-26	350	320	1266
	300	220	485	430	/	390	40	4	/	16-30	400	580	525	/	485	36	4	/	16-30	370	350	1283
A42Y-40C A42Y-40P A42Y-40R KA42Y-40 DA42Y-40(P)	20	15	105	75	51	55	16	2	4	4-14	25	115	85	/	65	16	2	/	4-14	110	95	378
	25	16	115	85	58	65	16	2	4	4-14	32	140	100	/	78	18	2	/	4-18	110	95	378
	32	20	140	100	66	78	18	2	4	4-18	40	150	110	/	85	18	3	/	4-18	115	100	378
	40	25	150	110	76	85	18	3	4	4-18	50	165	125	/	100	20	3	/	4-18	120	110	406
	50	32	165	125	88	100	20	3	4	4-18	65	185	145	/	120	20	3	/	4-18	135	120	450
	65	40	185	145	110	120	22	3	4	8-18	80	200	160	/	135	20	3	/	8-18	160	140	520
	80	50	200	160	121	135	22	3	4	8-18	100	220	180	/	155	22	3	/	8-18	170	135	525
	100	65	235	190	150	160	24	3	4.5	8-23	125	250	210	/	185	22	3	/	8-18	195	175	690
	125	80	270	220	176	188	28	3	4.5	8-26	150	285	240	/	210	24	3	/	8-23	210	190	780
	150	100	300	250	204	218	30	3	4.5	8-26	175	310	270	/	240	26	3	/	8-23	255	230	838
	200	125	375	320	260	282	38	3	4.5	12-30	250	405	355	/	320	30	3	/	12-26	300	260	992
	250	150	450	385	313	345	42	3	4.5	12-34	300	460	410	/	375	30	4	/	12-26	350	320	1266
A42Y-64 A42Y-64P A42Y-64R DA42Y-64(P)	20	10	125	90	51	68	22	2	4	4-18	25	115	85	58	65	16	2	4	4-14	110	100	264
	25	16	140	100	58	78	22	2	4	4-18	32	140	100	66	78	18	2	4	4-18	110	100	277
	32	20	155	110	66	82	24	2	4	4-23	40	150	110	76	85	18	3	4	4-18	130	110	289
	40	25	170	125	76	95	24	3	4	4-23	50	165	125	88	100	20	3	4	4-18	130	120	319
	50	32	180	135	88	105	26	3	4	4-23	65	185	145	110	120	22	3	4	8-18	155	130	389
	65	40	205	160	110	130	28	3	4	8-23	80	200	160	121	135	22	3	4	8-18	175	160	493
	80	50	215	170	121	140	30	3	4	8-23	100	235	190	150	160	24	3	4.5	8-23	175	160	483
	100	65	250	200	150	168	32	3	4.5	8-26	125	270	220	176	188	28	3	4.5	8-25	195	195	613
	150	88	345	280	204	240	38	3	4.5	8-34	200	375	320	260	282	38	3	4.5	12-30	285	260	894
A42Y-100 A42Y-100P A42Y-100R DA42Y-100(P)	20	10	125	90	51	68	22	2	4	4-18	25	115	85	58	65	16	2	4	4-14	110	100	264
	25	16	140	100	58	78	24	2	4	4-18	32	140	100	66	78	18	2	4	4-18	110	100	277
	32	20	155	110	66	82	24	2	4	4-23	40	150	110	76	85	18	3	4	4-18	130	110	289
	40	25	170	125	76	95	26	3	4	4-23	50	165	125	88	100	20	3	4	4-18	130	120	319
	50	32	195	145	88	112	28	3	4	4-26	65	185	145	110	120	22	3	4	8-18	155	130	389
	65	40	220	170	110	138	32	3	4	8-26	80	200	160	121	135	22	3	4	8-18	175	160	493
	80	50	230	180	121	148	34	3	4	8-26	100	235	190	150	160	24	3	4.5	8-23	175	160	483
	100	65	265	210	150	172	38	3	4.5	8-30	125	270	220	176	188	28	3	4.5	8-25	195	195	613
	150	88	355	290	204	250	46	3	4.5	12-34	200	375	320	260	282	38	3	4.5	12-30	285	260	894

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