Difference between gate valve and ball valve:

1 the valve core

Ball valve of the valve core to the sphere, because of its structure, fixed ball valve under the condition of high pressure, especially the closed state, the valve ball is fixed, the upper stem and lower fulcrum to decompose the part from the medium pressure, so the valve ball is not downstream migration, so the downstream seat stress in a number of relatively small, so the valve in the action to overcome the friction of the small, the seat wear is small, the valve's service life is long, especially for frequent movement of the valve and is more suitable for this kind of structure.

The valve core of the gate valve is a wedge disc or a parallel valve plate. The lower part has no pivot. Under high voltage application, so the valve and when closed, valve plate under the great pressure from the media, and as a result of its planar structure of valve plate, makes all the media pressure effect on the valve plate at the same time, the valve plate will now pressure downstream seat (at the same time, too much pressure on the vertical face of valve plate, makes the valve plate wedge or parallel double ram will have certain deformation), when the valve is in open to overcome a great deal of friction, is the seat of the wear print this short life of the valve.

2 the seat

The ball valve seat has a spring inside, and the sealing design of the seat area makes it difficult for the dregs in the medium to enter the seat area. And seat in the spring under the action of contact with the valve ball for a long time, so the valve, valve seat scraper role to a certain extent, can be in the long run after the dregs of the attached to the valve core to scrape off, therefore, which can ensure the valve sealing performance. Especially under high temperature and high pressure applications, due to the seat, the valve body, valve ball material when the choice to choose the same thermal expansion coefficient of the material, and the structure of the spring seat, so the valve in the closed, large temperature difference and temperature drop, will not affect the action of the valve, the valve will not produce the phenomenon that lock. Gate valve seats are very narrow, and when the valve is closed when the valve is closed, the temperature drops due to the lack of flow of the medium, so the seat will be tight, resulting in a large compression force on the valve plate. When the valve is opened again, a large torque is needed to overcome this tension, which can damage the seat and affect the seat life. Thus, the service life of valve is affected. In addition, due to the valve's self-weight during the closing, the valve will have a great impact and noise.

3 the trip

The stroke of the ball valve is angular travel, so the installation space is small and the height is low.

Gate valve is a straight stroke, so the installation space is large and high.

4 actuator

Due to the fixed ball design, the torque value of the opening and closing of the ball is small, so the actuator is equipped with a small amount. Due to the large pressure force of the valve plate to the seat, it is necessary to overcome this great friction force with great torque.

5 medium flow to double flow, no installation flow problem on site. Usually a single direction.

Long service life, short of ball valve.

7 maintain

There is no need to maintain, especially valve ball and seat, due to wear small, generally 5 years do not need to replace.

Due to the large wear of the seat, regular maintenance is required.