Wafer and lug butterfly valve
Butterfly valve application
Butterfly valve is suitable for pipelines conveying various corrosive and non-corrosive fluid media in engineering systems such as producer, coal gas, natural gas, liquefied petroleum gas, city gas, hot and cold air, chemical smelting, power generation and environmental protection. flow of the medium.
Lug butterfly valve
The lug design of the butterfly valve is somewhat similar to a 3-piece ball valve where one end of the wire can be removed without affecting the opposite side. This can be done by using threaded inserts, flanges and two sets of lugs (bolts) that do not use nuts, as each flange has its own bolt. It is thus convenient to clean, inspect, repair or replace the lug butterfly valve because you do not need to shut down the entire system.
Wafer butterfly valve
The primary function of the wafer butterfly valve is to maintain a seal that prevents bidirectional pressure differentials in the fluid flow to avoid any backflow in systems fabricated for one-way flow. This can be achieved by the use of tight fit seals (eg O-rings, gaskets, precision machined) and flat valve faces on the downstream and upstream portions of the valve.
Wafer VS Lug butterfly valve
There are four holes on the valve body of the wafer butterfly valve, and only need to use long bolts to penetrate the connection hole and flange hole of the wafer butterfly valve during installation. The installation is very convenient, the disadvantage is that the stability is poor.
There are two connection methods for lug butterfly valves:
- The through-type pressure hole, the installation method is the same as that of the wafer butterfly valve, and the stability is relatively poor compared with the flange connection.
- The installation method of the threaded hole type pressure hole is different from that of the wafer type and the flange type. At this time, the pressure hole of the lug type butterfly valve is equivalent to a nut. When connecting with the pipe flange, the bolt passes through the flange. The pressure hole of the lug butterfly valve can be directly tightened, and the bolts at the flange end are fixed with nuts. In this way, the stability is comparable to that of a flanged butterfly valve.