Single Seat Control Valve


What is a Single Seat Control Valve?

ZHP type single-seat control valve is a kind of top pilot single seat valve, which has a simple structure, well sealing, high flow rate and stable application performance. The reasonable top spiral system can avoid vibration during a small opening percentage, so as to extend valve working life.


Body type: straight through casting globe type
Spool type: non-balanced single seat plug type
Nominal size: DN20~200 NPS 3/4〞~ 8〞
Nominal pressure: PN16 ~ 100 CLASS 150LB ~ 600LB
Connection: flange: FF、RF、MF、RTJ
Welding: SW、BW
Flange dimension: acc. to IEC 60534
Bonnet type: standard type(-5℃~230℃)
Radiator type: (-45℃~ high than 230℃ occasion)
Low temperature extended type(-196℃~ -45℃)
Bellow seal type
Warm insulation Jacket type
Packing: V type PFTE packing, flex. graphite packing, etc.
Gasket: Metal graphite packing
Actuator: pneumatic: multi-spring diaphragm actuator, piston type actuator.
electric: 3810L series smart actuator, PSL series actuator.
Surface painting: Green color, acrylic acid polyurthene ceramic paint.


Z Actuator H Structure Nominal pressure Body material Nominal size
Z series control valve J: pneumatic diaphragm actuator
H: pneumatic piston actuator
R: electric 3810L actuator
D: electric PSL actuator
Direct travel P:  standard single seat
PF: soft-sealing single seat
PL: single-seat cage type
PG: radiator single-seat type
PV: bellow seal single seat
PD: low-temperature single seat
CL150LB=150 LB
D=special material
DN25= DN25
Such as Z type pneumatic diaphragm single seat control valve, PN16, body:  WCB, nominal size:  DN50, type:  ZJHP-16C DN50


Flow characteristic Linear, percentage, quick open
Allowable range 50: 1 (CV<6.3 30: 1)
Rated Cv value Percentage CV1.6~630 ,linear CV1.8~690
Allowable leakage Metal seal:  IV grade(0.01% rated capacity)
Soft seal:  VI grade(foam grade) Leakage standard:  GB/T 4213
Performance Pneumatic Electric
Intrinsic error % ±1.5 ±1.0
Return difference, % ≤1.5 ≤1.0
Dead zone, % ≤0.6 ≤1.0
The difference from beginning to endpoint, % ±2.5 ±2.5
Rated travel difference, % ≤2.5 ≤2.5

Note: specification on the basis of a control valve with positioner PTFE packing.

Special specification

Special test Material penetration flaw detection (PT), radiator test (RT), flow characteristic test,
low-temperature test.
Special treatment Trim nitrogen treatment, seat hard alloy treatment.
Special rinse Degreasing and dehydration treatment
Special condition Special piping or connection, vacuum condition, S.S fastener, special coating.
Special dimension Customized face to face length or dimension
Test and inspection Third-party test report

Single Seat Control Valve Actuator

Type\ Method Pneumatic diaphragm actuator Electric actuator
ZH23~ZH56 3810L series
Multi-spring type Intelligent integrated type
Usage Regulating type, an ON-OFF type Regulating
Air supply pressure or Power supply voltage Air supply pressure (Spring range)
140(20~100)Kpa G
240 (40~200) Kpa G
280 (80~240) Kpa G
Power: AC 200V±10%  50Hz
Or Power:  AC 380V±10% 50Hz
Connector Air pipe connector: RC1/4 Normal type:  cable inlet 2-PF(G1/2〞)
Explosive proof:  Protection jacket PF(G3/4〞)
Direct action Pressure increase, stem descend, valve close. Input signal increase, stem descend, valve close.
Reaction Pressure increase, stem ascend, valve open. Input signal increase, stem ascend, valve open.
Input signal 40~20mA.DC(with positioner) Input/output4~20mA.DC
Lag ≤1%FS(with positioner) ≤0.8%FS
Linear type 2%FS(with positioner) +1%FS
Environmental temperature -10℃~+70℃ Standard type: -10℃~+60℃
With space heater: -35℃~+60℃
Explosive proof: -10℃~+40℃
Surface coating Green, acrylic acid polyurethane coating Blue, acrylic acid polyurethane coating
Accessories E/P, P/P valve positioner, filter regulator, valve converter, solenoid valve, limited switch Space heater (normal type)

Note 1: non-standard accessories, need special customized notes.