Pneumatic diaphragm double seat control valve


Product model: ZMAN, ZJHN

Nominal diameter: DN25 ~ 300mm

Pressure range: PN1.6 ~ 6.4Mpa

Temperature range: - 40 ℃ ~ + 450 ℃

Flange size: GB / T9113.2-2000

Valve body type: double seat straight through type

Valve material: WCBZG230-450、ZG1Cr18Ni9Ti

Valve core material: 1Cr18Ni9Ti(304) or stellite alloy surfacing

Sealing packing: V-type polytetrafluoroethylene (F4), flexible graphite, stainless steel bellows


PRODUCT OVERVIEW

The pneumatic diaphragm double seat regulating valve is composed of a multi spring pneumatic diaphragm actuator and a straight through double guide double seat valve. It has the characteristics of compact structure, light weight, sensitive action, small pressure drop loss, large valve capacity and accurate flow characteristics. The compressed air drives the valve stem and spool to control the flow medium and realize the automatic regulation and control of the fluid medium in the process pipeline, It is applicable to clean media occasions where the leakage requirements are not strict and the pressure difference between the front and back of the valve is large. It is widely used in petroleum, chemical industry, pharmacy, metallurgy, power station and other industrial control fields, mainly controlling gas, liquid, steam and other media.


STRUCTURAL FEATURES

1. The pneumatic thin film actuator is equipped with positioner to accurately adjust and control the process parameters of fluid medium;

2. Positive action of actuator: air closed - normally open type (valve position moves downward when signal pressure increases), type B;

3. Actuator reaction: air open normally closed type (the valve position moves upward when the signal pressure increases), type K;

4. Double seat plunger valve core is suitable for occasions with large differential pressure, large flow, not very clean medium and lax leakage requirements.



MAIN TECHNICAL PARAMETERS

Nominal diameter(DN)253240506580100125150200250300
Seat diameter(dn)253240506580100125150200250300
Rated flow coefficient(KV)straight line12.519.530.548.47612519530548476010001600
Equal percentage1117,627.544691101762754406909001300
Allowable differential pressure(MPa)≤ Nominal pressure
Nominal pressure(MPa)1.6、2.5、4.0、6.4、10.0
Rated stroke(mm)16254060100
Matching actuator modelZHA/B-22ZHA/B-23ZHA/B-34ZHA/B-45ZHA/B-56
Bonnet formStandard type (- 17 ~ + 250 ℃), high temperature type (+ 250 ~ + 450 ℃), low temperature type (- 40 ~ - 196 ℃), bellows sealing type (- 40 ~ + 350 ℃)
Gland typeBolt compression type
Sealing packingV-type PTFE packing, V-type flexible graphite packing
Spool formDouble seat plunger guide valve core
Flow characteristicsStraightness, equal percentage


TECHNICAL PARAMETERS OF ACTUATOR

ambient temperature

Configure actuator categoryZHA/B Multi spring thin film actuator
Actuator modelZHA/B-22ZHA/B-23ZHA/B-34ZHA/B-45ZHA/B-56
Effective area(cm2)3503505609001400
Trip(mm)10、16244040、60100
Spring range(KPa)20~100(Standard)、20-60、60-100、40-200、80-240
Diaphragm materialNitrile rubber with nylon cloth, ethylene propylene rubber with nylon cloth
Air supply pressure140~400KPa
Air connectionRC1/4"
-30~+70℃
Accessories availablePositioner, air filter pressure reducer, holding valve, travel switch, valve position transmitter, hand wheel mechanism, etc
Action formAir off (B) - valve position open (FO) in case of gas loss; Gas open (K) - valve position closed (FC) in case of loss of gas


MATERIAL OF MAIN PARTS

1baseWCB304316316L
2Valve bodyWCB304316316L
3Spool304304316316L
4Valve seat304304316316L
5Copper sleeveBrass
6Guide sleeve304304316316L
7ShimPTFE\Graphite gasketPTFE\Graphite gasketPTFE\Graphite gasketPTFE\Graphite gasket
8Valve coverWCB304316316L
9Valve stem304304316316L
10FillerPTFE/GraphitePTFE/GraphitePTFE/GraphitePTFE/Graphite
11Packing glandWCB304316316L
12Bolt250Cr18Ni9Ti1Cr18Ni9Ti1Cr18Ni9Ti


MAIN PERFORMANCE INDEXES

ProjectWithout positionerWith locator
Basic error%±5.0±1.0
Return difference%3.01.0
Deadband%3.00.4
Deviation from starting point%Gas onStarting point±2.5±1.0
Starting point±5.0±1.0
Gas offStarting point±5.0±1.0
End±2.5±1.0
Rated stroke deviation%2.5
Leakage L / h0.01%×Valve rated capacity
Adjustable range R30:1


MAIN CONNECTION DIMENSIONS

Nominal diameterDN(mm)253240506580100125150200250300
LPN16/25185200220250275300350410450550670770
PN40190210230255285310355425460560740805
PN64200210235265295320370440475570750820
HPN16/25117120139144188208220268278320441503
PN40124128145150195220230280290335465528
PN64130135155170205240255295310360480550
H1165185185205245255270335365430560680
H2298298298298380380380510510510650650
H3177177177177182182182182182218218218
L1280280280280350350350475475475560560
A282282282282360360360470470470580580
D220220220220270270270320320320400400

Product recommendations

+86-577-67383555
qrCode