Summary:The closing part of the butterfly valve is a disc, which rotates around a fixed axis in the valve body to open, close an...
The closing part of the
butterfly valve is a disc, which rotates around a fixed axis in the valve body to open, close and adjust the fluid channel.
1. Advantages
Simple structure, small size and light weight;
Under low pressure, a good seal can be achieved;
It is convenient and quick to open and close, labor-saving, small fluid resistance, and can be operated frequently;
Slurry can be transported with minimal accumulation of liquid at the pipe mouth;
Good adjustment performance.
2. Disadvantages
poor sealing;
The operating pressure and operating temperature range are small.
Butterfly valves are developing the fastest now, and are developing in the direction of high temperature, high pressure, large diameter, high sealing, excellent adjustment performance and long life, and have partially replaced gate valves, globe valves and ball valves.
According to the structure, butterfly valves can be divided into central sealing type, single eccentric sealing type, double eccentric sealing type and triple eccentric test butterfly valve. The center seal type belongs to the earlier butterfly valve form; compared with the center seal type, the single eccentric seal butterfly valve has a more complex structure, slightly higher cost, better sealing performance, longer service life and higher operating pressure; double eccentric seal type and Compared with the single eccentric butterfly valve, the triple eccentric butterfly valve has more complex structure, higher manufacturing cost, better sealing performance, longer service life and higher operating pressure.
The characteristics of the industrial butterfly valve are high temperature resistance, high applicable pressure range, large nominal diameter of the valve, carbon steel for the valve body, and metal ring instead of rubber ring for the sealing ring of the valve plate. Large high temperature butterfly valve is made of steel plate welding, mainly used for flue air duct and gas pipeline of high temperature medium.
Installation and maintenance should pay attention to the following matters:
During installation, the valve disc should stop in the closed position;
The opening position should be determined according to the rotation angle of the butterfly plate;
For butterfly valves with bypass valves, the bypass valve should be opened before opening;
It should be installed according to the manufacturer's installation instructions. For butterfly valves with heavy weight, a firm foundation should be set up.