Check Valves Series : VC31

Check Valves (Non-Return Valves) Series : VC31

DAWSONS-TECHCheck Valve Series : VC31 is a very compact and robust in construction and design for unidirectional flow control of fluids and gases for medium pressure (UPTO 3000 PSIG) used in Instrumentation systems.

Features :
  • Back stopped poppet design to minimum spring stress.
  • ‘O’ Ring bonded poppet seat provides leak tight seal.
  • Provides large flow, minimum of chatter and fluctuation.
  • Variable cracking pressure: 1/3, 1.5, 10, 25 and 100 PSIG.
  • Suitable for Vacuum and high-pressure applications.
  • Available in Material SS316L.
  • Every valve is pressure tested.

Operating Parameters :
  • Pressure Rating: UPTO 3000 PSIG (207 Bar) at CWP.
  • Temperature Rating: UPTO 198o C with with Fluorocarbon 'O' Ring.
  • End Connections:
    • Inch: 1/4" to 1” Tube OD
    • Metric: 6mm to 25mm Tube OD
    • Tube OD Pipe Thread: 1/4" to 1” Male / Female BSP / BSPT / NPT
    • Face Seal: 1/4" to 1”
    • ‘O’ Ring Face Seal: 1/4" to 1”
Applications :
  • Gas, Liquid, Fluid Handling.
Type Test Approvals :
The design of DAWSONS-TECH Valves Series : VC31 have been tested for Hydrostatic Proof and Burst Test in accordance with MSS SP-99-2016a Clause 5.5 & 5.6.
Testing :
  • Standard Test : Each Valve is pressure tested with Nitrogen at 1000 PSIG (69 Bar) for leakage at the seat and packing.
  • Optional Hydrostatic Test : This test is performed with De-ionized water at 1.5 times the working pressure.
Certification :
The certificate to 3.1 acc. to EN10204 for Valves Body Material and pressure test will be provided on request.
Material of Construction :
Sr. No.DescriptionMaterial
1Inlet BodySS316
2‘O’ RingFluorocarbon
3PoppetSS316
4SpringStainless Steel
5‘O’ RingFluorocarbon
6Outlet BodySS316
Pressure & Temperature Rating :
Material SizeSS316L
1/8” to 1/2" 6mm to 12mm3/4" to 1” 22mm to 25mm
Temperature FO (CO)Working Pressure, PSIG (Bar)
-10°F (-23°C) to 100°F (37°C)3000 PSIG (207 Bar)2550 PSIG (176 Bar)
200°F (93°C)2575 PSIG (177 Bar)2180 PSIG (151 Bar)
250°F (121°C)2450 PSIG (168 Bar)2010 PSIG (139 Bar)
300°F (148°C)2325 PSIG (160 Bar)1910 PSIG (132 Bar)
375°F (190°C)2185 PSIG (150 Bar)1790 PSIG (124 Bar)

CRACKING AND RESEAL PRESSURE
Cracking Pressure*Cracking Pressure RangeReseal Pressure**
PSIG (Bar)PSIG (Bar)PSIG (Bar)
1/3 PSIG (0.02 Bar)UPTO 3 PSIG (0.2 Bar)6 to 20 PSIG (0.4 to 1.3 Bar) Back Pressure
1 PSIG (0.06 Bar)UPTO 4 PSIG (0.27 Bar)5 to 20 PSIG (0.34 to 1.3 Bar) Back Pressure
5 PSIG (0.34 Bar)3 to 9 PSIG (0.20 to 0.62 Bar)5 to 20 PSIG (0.34 to 1.3 Bar) Back Pressure
10 PSIG (0.68 Bar)7 to 15 PSIG (0.48 to 1.0 Bar)3 to 10 PSIG (0.2 to 0.68 Bar) Back Pressure
25 PSIG (1.7 Bar)20 to 30 PSIG (1.3 to 2.0 Bar)5 PSIG (0.34 Bar) or more Inlet Pressure
* CRACKING PRESSURE
  • The differential pressure between the inlet and outlet, at which an initial flow is passing through the Valve.

    ** RESEAL PRESSURE
    • The differential pressure between the outlet and inlet, at which no flow is passing through the Valve.
      Connection SizesCracking Pressure PSIG (Bar)Max. Flow Coefficient (Cv)Back Pressure at 70OF (20OC) PSIG (Bar)
      1/8”, 1/4", 6mm1/3 PSIG (0.02 Bar), 1 PSIG (0.06 Bar)0.753000 PSIG (207 Bar)
      3/8”, 1/2" 8mm - 12mm5 PSIG (0.34 Bar), 10 PSIG (0.68 Bar)2.263000 PSIG (207 Bar)
      3/4", 1”, 22mm, 25mm25 PSIG (7.1 Bar)6.562550 PSIG (176 Bar)
      End ConnectionFlow DataA (mm)A/F (Inch)Dawsons-Tech Part No.
      TypeSizeOrifice (mm)Cv
      Metal Gasket Face Seal1/44.60.7250.03/4VC31-GFS4
      1/29.52.9383.31-1/4VC31-GFS8
      3/412.75.6396.01-3/8VC31-GFS12
      ‘O' Ring Face Seal1/44.70.7556.43/4VC31-ORF4
      1/210.33.1790.41-1/4VC31-ORF8
      3/415.16.01117.91-3/8VC31-ORF12
      Male NPT1/44.70.7555.43/4VC31-MM4N
      3/89.12.2675.21VC31-MM6N
      1/211.53.53.90.41-1/4VC31-MM8N
      3/415.16.01103.91-3/8VC31-MM12N
      116.76.56114.81-5/8VC31-MM16N
      Female NPT1/44.70.7561.03/4VC31-FF4N
      3/89.12.2677.01VC31-FF6N
      1/211.53.5390.41-1/4VC31-FF8N
      3/415.16.01103.91-3/8VC31-FF12N
      116.76.56122.91-5/8VC31-FF16N
      Fractional Tube Fitting1/44.70.7561.53/4VC31-TT4
      3/87.12.0983.11VC31-TT6
      1/210.73.53103.61-1/4VC31-TT8
      3/415.16.01110.21-3/8VC31-TT12
      116.76.56117.61-5/8VC31-TT16
      Metric Tube Fitting6 mm4.70.7561.73/4VC31-TT6M
      8 mm6.42.0284.61VC31-TT8M
      10 mm7.92.1685.11VC31-TT10M
      12 mm9.52.93103.11-1/4VC31-TT12M
      22 mm15.16.01109.21-3/8VC31-TT22M
      25 mm16.76.56120.41-5/8VC31-TT25M
      Dimensions are for reference only and are subject to change.