Double Flange Butterfly Valve is a vertical plate structure. The valve stem is a one-piece metal hard-sealed valve. The sealing ring is a composite structure of flexible graphite plate and stainless steel plate. It is mounted on the valve body and the sealing surface of the butterfly plate is welded with stainless steel. The seal of the soft seal valve is made of nitrile rubber and is mounted on the disc.
ZFV offers a wide range of standard valves to meet the needs of customers around the world, including: API609 / ANSI / ASTM standards, AWWA / AWWA C207 standards, EN593 / DIN / BS standards, ISO standards, JIS / JIS B2220 standards, GOST / GOST 54432 standards Wait.
* Size : DN300
* Pressure : PN16
* Connection Type : Flange ends Valve
* Torque : 2200/N.m
* Operation : Manual gear box with handwhel
* Cv figure in Full Open Position : 3520
* Face to face length : 178mm
* Valve Structure : three eccentric / triple offset
* Seal Structure : stainless steel + graphite layer
* Application : Chemical application
* Material Heat Treatment : Solution treatment.
* Need Extended Stem : No
* Suitable Temperature : -29°C ~ 200°C
* Suitale Pressure : PN<16Bar
* Suitable service : W.O.G. Acid. Corrosive service .
* Provide Matching Flanges and bolts : Availale
* Function : Shutoff & regulation
* Material : body material austenite A351 CF8, disc A351 CF8, seal SS316 + graphite, stem A182 F304
* Standard : Design and manufacture BS EN593
Face to face dimension BS EN558
End flanges dimension BS EN1092-1
Test & inspection as BS EN12266-1
* Origin : Wenzhou , China.
* Supplying Mode : OEM production & ZFV brand .
* EN 10204-3.1 certificate shall be provided along with valves.
Double Flange Butterfly Valve's sealing structure is a composite valve seat made of PTFE, synthetic rubber and phenolic resin, which makes the valve seat more elastic and stronger. At the same time, the butterfly plate is completely covered with PTFE, so that the butterfly plate has strong corrosion resistance. The Double Flange Butterfly Valve is characterized by the fact that the elasticity of the valve is still provided by synthetic rubber and utilizes the advantages of low friction coefficient, low wear resistance and aging resistance of the Teflon, so that the life of the butterfly valve can be improved.
Valve pressure testing should be handled in accordance with the following general requirements:
-- For special structural valves (excluding oil seals that allow injection into the sealing surface or fill valve) and emergency seal grease, the injection system should be hollow and ineffective during the test.
- When using a liquid test, the air in the chamber should be exhausted.
- Prior to shell testing, the valve shall not be painted or coated with other coatings that mask surface defects (phosphorization or similar chemical treatment is allowed to protect the valve surface prior to testing, but voids, pores and blisters should not be hidden, etc. Defect)
- When sealing tests are applied to gate valves, plug valves and ball valves, the body cavity between the cover and the sealing surface should be filled with media and pressurized to the test pressure to avoid leaks due to undetected seals. The medium and pressure are gradually filled onto the above components during the test.
- When performing the sealing test, no external force should be applied to both ends of the valve, which will affect the leakage of the sealing surface. The operating torque of the closing valve should not exceed the closing torque of the valve design.
-- For the visible leakage of the valve pressure test, the housing grinding and upper sealing tests are not allowed. If the test medium is a liquid, there should be no visible droplets or surface moisture. If the test medium is air or other gas, there should be no air bubble leakage. There should be no structural damage during the test.
-- For low pressure seal testing of valve pressure test and high pressure seal test, visible leaks are not allowed to pass through the valve identification, the contact surface between the valve seat and the valve body, and there is no structural damage. Reference Standard API 598 Test Test Allowable Test Medium Leakage Rate Through Sealing Surface Duration