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Multilayer Metal Seal Bidirectional City Gas Butterfly Valve

Multilayer Metal Seal Bidirectional City Gas Butterfly Valve

    The SV multilayer metal seal bidirectional city gas butterfly valve is designed for city gas pipeline to meet the demand of isolation and throttling. The SV multilayer metal seal butterfly valve adopts the triple offset structure design and resilient multilayer metal seal structure to ensure bidirectional tight shutoff and long service life.

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  • Features
  • Specification

  • The SV multilayer metal seal city gas butterfly valve sealing ring of disc is composed by stainless steel plate and carbon fiber. The stainless steel sheet is primary seal and the carbon fiber is secondary seal. The double seal structure ensures reliable seal and the seal leakage grade up to ASME B16.104 VI class and ISO5208 A class;
  • Compared with rubber asbestos plate and graphite, the carbon fiber is more environmental protection, more wearable, more reliable against erode, up to 200,000 times of non-failure open and close;
  • The SV bidirectional city gas butterfly valve body seat fixed by two counter rings through bolts can be replaced easily;
  • Dynamically balanced sealing system makes the pressure at inlet and outlet side of disc almost balanced so that the butterfly valve will achieve reliable bidirectional seal while the operate torque is reduced effectively to almost 2/3 of normal butterfly valve;
  • The unique triple offset design eliminates friction between the disc seal ring and body seat, thereby preventing wear and any consequent leakage to extend service life.

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Product range:

  • End connection: Flanged, Wafer, Lugged, BW
  • Size: 1"144" (DN253600)
  • Pressure rating: Class 1501500 (PN2.5PN260)
  • Operation: Bare stem, Lever, Gearbox and handwheel, Electric, Pneumatic
  • Body materials: Carbon steel WCB/A105, Low temperature steel LCB/LCC/LC3, High temperature steel WC6/WC9/C5/C12A, Austenitic stainless steel CF8/CF8M/CF8C/CF3/CF3M/CG8M, Super austenitic stainless steel 254SMO A351 CK-3MCuN, Duplex stainless steel UNS S31803/UNS S32205/N08904, Super duplex stainless steel UNS S32750/UNS S32760, Titanium alloy B368 gr.C-2, Hastelloy C276, Monel alloy A494 M-35-1, Aluminum bronze B148 C95800, Inconel 625, Incoloy 825, Alloy 20 CN7M etc.
  • Disc seal ring: SS304, SS316 with flexible graphite or carbon fiber
  • Body seat materials: SS304, SS316, Stellite etc.
  • Stem materials: SS420, 17-4PH, SS304, SS316 etc.
  • Disc materials: WCB, CF8, CF8M, 904L, C95800 etc.

Technical standards:

  • Design: ASME B16.34, DIN 3840
  • Face to Face: API 609,ASME B16.10, ISO5752
  • BW ends: ASME B16.25, ASME B31.8, EN12627
  • Flanged ends: ASME B16.5, ASME B16.47, EN1092
  • ISO top flange: ISO5211
  • Materials: NACE MR 01-75
  • Wall thickness: ASME B16.34
  • Test and inspection: API 598
  • Fireproof test: API 607, API 6FA
  • Pressure and temperature rating: API609, ASME B16.34