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HOME >> PRODUCTS >> SSV-A400 Safety Shut-off Valve

SSV-A400 Safety Shut-off Valve

Applicable for offtake stations in gas transmission and distribution system, for gas supply to industrial and power pants.

Safety device for gas pressure regulating stations

Suitable for natural gas and all other non corrosive gaseous media


※Low pressure drop due to in-line flow design

※Replace internal parts without dismantling the valve from the line

※Equipped with pressure compensating valve

※Emergency manual release local position indicator standard

※Electric release and electric remote indication of valve position available

※High response accuracy and short response time

※Max. flow rate should not exceed 80 m/sec, noise <80dB

※TUV SIL 3 certificate according to SIL-norm IEC 61508 IEC 61511

Technical Data

Function and Strength EN14382
Nominal Pressure CLass150~1500 (2.0MPa~26MPa)
Nominal Size DN25~DN400(NPS 1” ~NPS 16”)
Connections Flanged ANSI B16.5 RF/RTJ
Temperature Class -29℃~60℃, -46℃~60℃
Accuracy Class ±1%(AG1), ±2.5%(AG2.5), ±5%(AG5)
Response Time s~1s
Explosion-proof/Protection Class Up to ExdIIBT4, IP65
Materials Main valve body:   Cast steel  A 216 WCB、A 352 LCC
Pilot :    Cast steel, forged steel, forged aluminum  
Internal part:  Stainless steel, steel, copper, aluminum
Spring:    Spring steel (X750,A276,316)
Sealing:    Reinforced PTFE, NBR, synthetic rubber


Operating principle

Safety shut-off valve is controlled by pilot . Overpressure or underpressure release feature is when monitored downstream operating pressure exceeds set-point range, the pressure signal fed back to the pilot (pilot valve), the pilot piston moving up or moving down, so that the trolley trip, hammer down the impact of the firing pin and firing pin moves down makes disengage the hook and flap, flap valve is closed down, thereby cutting off gas to the downstream pipeline, protect downstream equipment and pipeline safety.


Valve Design

Command Design




SSV - A400  DN25 – DN150

SSV - A400  DN250 - DN400


The sampling point pressure piping connecting dimensions



Pressure sampling point mounting position

As shown in Figure 1 and 2, the safety shut-off valve (SSV) pressure sampling point is 5-8xDN from the working valve (PCV or PV) .

Product order type selection

Shut-off valve selection

Pilot selection


Other special feature


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