The lug type butterfly valve in ductile iron, Carbon steel or stainless is available with various seal options from Buna, EPDM, Teflon or Metal Faced. Handle or wheel options are available. Additional mounting of actuator limit switches Andy gear boxes are optional. A wafer butterfly valve’s function is to retain a seal to protect against dual-directional pressure differential in the flow of fluid. In other words, the wafer version of butterfly valves was designed to hold a tight seal, safeguarding against bi-directional pressure differential in order to avoid any backflow in systems that have been manufactured for uni-directional flow. This is accomplished by using a tightly fitted seal, such as an O-ring, gasket, precision machined, along with a flat valve face on the downstream and upstream sections of the valve.
Lug Wafer Type Butterfly Valve
Description
Lug-style valves have threaded inserts at both sides of the valve body. This allows them to be installed into a system using two sets of bolts and no nuts. The valve is installed between two flanges using a separate set of bolts for each flange. This setup permits either side of the piping system to be disconnected without disturbing the other side.
A lug-style butterfly valve used in dead end service generally has a reduced pressure rating. For example a lug-style butterfly valve mounted between two flanges has a 150 psi pressure rating. The same valve mounted with one flange, in dead end service, has a 75 psi rating.
Technical Specifications
| Nomidal Diameter | DN(mm) | 50~2000 | ||
| Nominal Pressure | PN(Mpa) | 0.6 | 1 | 1.6 |
| Test Pressure | Shell Test | 0.9 | 1.5 | 2.4 |
| Sealing Test | 0.66 | 1.1 | 1.76 | |
| Air Test | 0.6 | 0.6 | 1.76 | |
| Suitable Medium | Air, water, sewage, steam, gas, oil, etc | |||
| Actuator | Handle, gear, electric actuator, pneumatic actuator | |||
Main Parts & Materials
| Part Name | Part Name |
| Body | Cast iron, ductile iron, cast steel, stainless steel, rubber-lined, PTFE-lined, etc |
| Disc | Cast iron, ductile iron, cast steel, stainless steel, special materials |
| Seat Ring | Ductile iron, cast steel, stainless steel, alloy steel |
| Stem | 45#, 2Gr13, stainless steel |
| Packing | O-Ring, soft graphite |
