• The YFL metal seal triple eccentric butterfly valve with triple offset design completely eliminates friction between valve seat and seal ring of the disc throughout the total stroking process from open to close with the only point of contact occurring within the final stage of closure and extends the service life greatly;
• The material of disc seal ring can be changed from soft materials to metal  duo to zero friction so that the triple offset metal seal butterfly valve can be suitable for high temperature working condition;
• The YFL metal seated triple offset butterfly valve with triple offset design changes the seal structure from position seal to torque seal, the seal is not achieved by elastic deformation of seat but by contact surface pressure of seat which is proportional to the service pressure, so the triple offset butterfly valve can achieve reliable seal under high pressure.
• The disc seal ring can be multilayer metal seal with materials of stainless steel and graphite or full metal seal with materials of stainless steel overlaid stellite alloy. 

Product range:

• Size: 1"～144" (DN25～3600)
• Pressure rating: Class 150～1500 (PN2.5～PN260)
• End connection: Flanged Wafer Lugged BW
• Body materials: WCB A105 LCB WC6 WC9 CF8 CF8M C95800 etc.
• Disc materials: WCB CF8 CF8M 904L C95800 etc.
• Stem materials: stainless steel SS420 F304 F316 etc.
• Seat materials: 13Cr+hard face integral seat on body
• Seal ring: SS304+graphtie SS316+graphtie etc.
• Operation: Bare stem lever gearbox and handwheel electric pneumatic.

Technical standards:

• Design: API609
• Face to Face: 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
• Wall thickness: ASME B16.34
• Test and inspection: API 598
• Fireproof test: API 607 API 6FA
• Pressure and temperature rating: API609 ASME B16.34