Views: 208 Author: Site Editor Publish Time: 2021-10-11 Origin: Site
Butterfly valve is a kind of valve which can open, close, or adjust the medium flow by turning the disc opening-closing piece, which not only has the advantages of simple structure, small volume, light weight, low material consumption, small installation size, small driving torque, and rapid operation, but also has good flow regulation function and closing sealing characteristics. Double flanged butterfly valve is one of the fastest growing valve varieties in recent years, which is widely used. Electric actuated butterfly valve began to develop to high temperature, high pressure, large diameter, high sealing, long life, excellent regulation characteristics, and multi-function integration, whose reliability and other performance indicators have reached a high level.
With the application of chemical resistant synthetic rubber in triple eccentric butterfly valve, the performance of butterfly valve is improved. Synthetic rubber has the characteristics of corrosion resistance, erosion resistance, dimensional stability, good resilience, easy forming, and low cost, which can meet various working conditions of split butterfly valve according to different requirements.
Polytetrafluoroethylene (PTFE) has the characteristics of strong corrosion resistance, stable performance, not easy aging, low friction coefficient, easy forming, and stable size, which can also improve its comprehensive performance by filling and adding appropriate materials, so as to obtain butterfly valve sealing materials with better strength and lower friction coefficient. Polytetrafluoroethylene (PTFE) overcomes the limitation of synthetic rubber, so the polymer material and its filling modified material represented by polytetrafluoroethylene have been widely used in grooved butterfly valve, so as to manufacture butterfly valve with wider temperature and pressure range, reliable sealing performance, and longer service life.
In order to meet the requirements of severe temperature change, strong erosion, long life, and other industrial applications, metal seal electric butterfly valve has been greatly developed. With the application of high temperature resistance, low temperature resistance, strong corrosion resistance, strong erosion resistance, and high strength alloy materials in concentric butterfly valve, metal seal butterfly valve has been widely used in industrial field and centerline butterfly valve with large diameter (9 ~ 750mm), high pressure (42.0mpa), and wide temperature range (- 196 ~ 606 ℃) has appeared, which makes butterfly valve technology reach a new level.
The eccentric butterfly valve has a small flow resistance when fully opened, and the butterfly valve can carry out sensitive flow control when opened at about 15 ° to 70 °, so it is widely used in the field of large diameter regulation.
1) The installation position, height, inlet, and outlet direction must meet the design requirements.
2) The handle of all kinds of manual valves installed on the insulation pipeline shall not be downward.
3) The butterfly valve with supervisory switch must be visually inspected before installation and the valve name plate shall comply with the provisions of the current national standard "general valve marks" GB 12220. For the valve with working pressure greater than 1.0 MPa, the strength and tightness test shall be conducted before installation. The strength test requires that the test pressure is 1.5 times of the nominal pressure and the duration is not less than 5min. Only when there is no leakage in valve shell and packing can the product be qualified. During the tightness test, the test pressure shall be 1.1 times of the nominal pressure and the test duration shall meet the requirements of GB 50243.
