What butterfly valve is used on the water pipe

There are many kinds of butterfly valves, and various kinds of butterfly valves can be used in many occasions, so what butterfly valves will be used above the water system pipes, do you know?

1. Wafer butterfly valve and eccentric butterfly valve. Wafer butterfly valve and eccentric butterfly valve have advantages and disadvantages, selection should be combined with its cost performance to comprehensive consideration. In general, the center line butterfly valve is cheaper than the eccentric butterfly valve. The wafer butterfly valve is closed and sealed, in essence, a rubber lining extrusion seal, especially near the valve shaft, so that the service life of the valve is affected, and the opening and closing torque of the valve is larger. In order to reduce the shortcomings of the eccentric butterfly valve, the theoretical sealing state is a contact sealing state, the eccentric butterfly valve is directional in the bearing water pressure, especially the three-dimensional eccentric butterfly valve reverse pressure ability is weak. Because the pipe network is annular, the requirements for the valve to bear pressure in both directions are the same, so the valve selection should emphasize this requirement.

2. Vertical and horizontal butterfly valves. In medium and large butterfly valves, there are differences between vertical and horizontal valve shafts. Usually, vertical butterfly valves are covered with deep soil, and debris in water is easy to wrap around the shaft end, affecting the opening and closing; The variable speed transmission box of the horizontal butterfly valve is on the side, and the plane position of the valve well on the road is wider, which affects the arrangement of other pipelines. Therefore, in view of the above problems, it must be clear in the selection process of the valve: the medium-sized caliber butterfly valve is mainly vertical, and the large-caliber butterfly valve is horizontal under the condition that the plane position is permitted. This will not only greatly improve the flow conditions of the valve, but also completely solve the problem of water debris winding the valve shaft.

3. Soft seal and metal seal butterfly valve. Most of the butterfly valves used in the water supply industry are soft-sealed butterfly valves, and there are some problems in the use of this sealing method.

① The main problems in the use of soft seal butterfly valve are: poor rubber quality, easy aging, long-term compression deformation, extrusion cracking.

Due to the small elasticity of the seal, the metal sealed butterfly valve generally uses an eccentric structure, especially the three-dimensional eccentric structure is ideal. The metal sealed butterfly valve was originally used in the high-pressure steam pipe, the price is more expensive, it is not easy to damage the sealing surface in operation, but its manufacturing accuracy requirements are high, once the leakage is difficult to repair.