The reasons for choosing correct type butterfly valve:
When engineer design the working flow system, they need to consider the properly selection of valves. Butterfly valve can widely apply to many flow situation. We normally install concentric butterfly valve, double eccentric butterfly valve and triple eccentric butterfly valve for right application
Since the pressure loss of the butterfly valve in the pipeline is large. And it is about three times of gate valve. So when selecting the butterfly valve type, we need fully consider the influence of the pressure in pipeline system. We need consider the pressure of the butterfly plate to withstand the pressure of the pipeline as well.
Additionally, engineer should consider the limits of the operating temperature of the elastomeric seat material at elevated temperature.
The butterfly valve has below characters as:
small structural length
small overall height
fast opening and closing speed
good fluid control characteristics
The structural principle of the butterfly valve is most suitable for making a large diameter valve. When the butterfly valve is apply on control flow, the size and type of the butterfly valve are selected correctly. The correct selection could make the system work properly and efficiently.
Suitable for butterfly valve working conditions:
Generally, in throttling, regulating control and mud medium, the structural length requires to be short. And the opening and closing speed is fast (1/4 turn). Low pressure cut-off (small pressure difference), it recommends to apply butterfly valve.
In the double position adjustment, shrinkage channel, low noise, cavitation and gasification phenomenon. A small amount of leakage to the atmosphere, with abrasive media, we can use butterfly valve.
In the case of throttling adjustment under special working conditions, or when the sealing is strict. The butterfly valve work under severe working conditions such as severe wear and low temperature (deep cold). Under these solution, it requires special eccentric or double eccentric butterfly valve with metal sealing and band adjusting devic.
The midline butterfly valve is suitable for fresh water, sewage, seawater, salt water. As well as steam, natural gas, food, medicine and oil that require complete sealing. And zero gas test leakage, high life expectancy and working temperature between -10 °C and 150 °C. And a variety of acid and alkali and other pipelines.
Soft-sealed eccentric butterfly valve is suitable for two-way opening and closing and regulation of ventilation and dust removal pipelines. It widely applies in gas pipelines and waterways of metallurgy, light industry, electric power and petrochemical systems.
Metal-to-metal wire sealed double eccentric butterfly valve is suitable for urban heating. Also for gas supply, water supply and other gas, oil, acid and alkali pipelines, as a regulation and throttling device.
Metal-to-metal sealing triple eccentric butterfly valve widely apply in petroleum, petrochemical, chemical, metallurgical, electric power and other fields. In addition to being used as a large-scale pressure swing adsorption (PSA) gas separation device program control valve.
