ZFV Low temperature butterfly valve. For using in cryogenic situation, extended stem/bonnet design shall be applied. Extended stem/bonnet butterfly valve can be provided by ZFV according to customer requirement. Generally extended valve may be used in these conditions: 1.Protect packing material; 2.it is convenient to apply cold holding material for low temperature media pipeline; 3.easier to operate as per actualy needs.
ZFV can provide extended butterfly valve with various size, pressure and material .
Products : Low temperature butterfly valve
* Size : DN400
* Pressure : PN16
* End Type: Full LUG ends
* Operation : Gear box with Manual Handwheel
* Torque : 3700/N.m
* F-F length : 102mm
* Design Structure : triple offset
* Seal type : stainless steel layer laminated with graphite
* Application : Chemical Industry application
* Need Extended Stem : Yes
* Suitable Temperature : -46°C ~ 200°C
* Suitale Pressure : not higher than 1.6Mpa
* Suitable service : W.O.G , low temperature service
* Provide Matching Flanges and bolts : Availale in need
* Function : Shutoff
* Material : body SS304L ( A351 CF3 ),
disc SS304L ( A351 CF3 ),
seal laminated SS316+graphite.
stem SS304L ( A182 F304L )
* Standard : Design API609
F-F dimension API609
Flanges dimension ASME B16.5
* Origin : Wenzhou , ZJ Provice, China
* EN 10204-3.1 certificate
* Third Part Inspection : Acceptable
Cryogenic Valve is valve suitable for service that temperature -46 Degree C ~ -196 Degree C, , these valves are generally used extended-stem or extended-bonnet design.
The reasons to use used extended-stem or extended-bonnet design:
(1) The extended-stem has the function of protecting the stuffing box of the cryogenic valve, because the tightness of the stuffing box is one of the keys of the cryogenic valve. If the packing box leaks, it reduces the cooling effect and cause the liquefied gas to vaporize. As a result of media leakage, ice is formed on the filler and the stem, affecting the normal operation of the stem and simultaneously moving the stem up and down. Filler scratches, causing serious leaks. Therefore, need to ensure that the temperature of the stuffing box is under 8 degree C.
(2) The extended-stem or extended-bonnet structure facilitates the jacketing material of gryogenic valve and prevents the loss of cold energy of cryogenic valves.