When should you use a butterfly valve
If you want to know where the butterfly valve is applied, you must first know the characteristics and advantages of the butterfly valve: Advantages and disadvantages of choosing a butterfly valve
Butterfly valves are mainly used to control a fluid’s flow rate. Depending on what material the valve is made of, it can be used for different types of fluids: chemically neutral fluids such as water or oil, sludge, food products or pharmaceutical fluids and some butterfly valves can be specially designed to operate with corrosive fluids. A butterfly valve cannot be used for fluids containing solid particles however as they could prevent it from closing completely.
The butterfly valve is a quarter-turn valve. It requires a 90° rotation between the open and closed position to operate. For large diameters, it may require an actuating system equipped with a gearbox that compensates for the pressure exerted directly on the valve.
Butterfly valves are designed to ensure a good sealing system. Large diameter butterfly valves often use flange mounting, and those intended for heating circuits, for example, are generally screw-in valves. Butterfly valves usually have a minimal space requirement, especially compared to ball valves.
Where should butterfly valves be used
Generally, in throttling, regulating control and mud medium, the structure length is required to be short, and the opening and closing speed is fast (1/4 revolution). Low pressure cut-off (small pressure difference), butterfly valve is recommended.
Butterfly valve can be used when two-position adjustment, narrow passage, low noise, cavitation and vaporization phenomenon, a small amount of leakage into the atmosphere, and abrasive media.
When the butterfly valve is used under special conditions such as throttling adjustment, or strict sealing requirements, or severe wear, low temperature (cryogenic), etc., a special designed metal seal with an adjustment device for triple eccentric or double eccentricity is required Butterfly valve.
The centerline butterfly valve is suitable for fresh water, sewage, sea water, salt water, steam, natural gas, food, medicine, oil and various products that require complete sealing, zero gas test leakage, high life requirements, and working temperature of -10℃～℃. Acid-base and other pipelines.
The soft-sealed eccentric butterfly valve is suitable for two-way opening and closing and adjustment of ventilation and dust removal pipelines. It is widely used in gas pipelines and waterways in metallurgy, light industry, electric power, and petrochemical systems.
The metal-to-metal wire sealing double eccentric butterfly valve is suitable for urban heating, gas, water supply and other gas, oil, acid and alkali pipelines, as a regulating and throttling device.
In addition to being used as a large-scale pressure swing adsorption (PSA) gas separation device program control valve, the metal-to-metal seal triple eccentric butterfly valve can also be widely used in petroleum, petrochemical, chemical, metallurgical, electric power and other fields. It is a good gate valve and stop valve. replacement product.
Selection principle of butterfly valve
- Since the pressure loss of the butterfly valve is relatively large compared with the gate valve and the ball valve, it is suitable for piping systems with less stringent pressure loss requirements.
- Since the butterfly valve can be used for flow adjustment, it is suitable for use in pipelines that require flow adjustment.
- Due to the limitation of the structure of the butterfly valve and the sealing material, it is not suitable for high temperature and high pressure piping system. Generally, the working temperature is below 300℃, and the nominal pressure is below PN40.
- Since the structure length of the butterfly valve is relatively short and it can be made into a large orifice, it is appropriate to choose a butterfly valve in the occasion where the structure length is required to be short or a large orifice valve (such as DN1000 or more).
- Since the butterfly valve can be opened or closed by only rotating 90°, the butterfly valve should be used in the occasions that require fast opening and closing.