Functional classification
1. Bypass valve: The ball valve is generally opened with still water, so the bypass valve is set for flat pressure first, that is, fill with water on both sides;
2. Air valve: When filling water, remove the air and take the buoy to close the valve by yourself; When discharging water, replenish air and the buoy will descend by itself;
3. Pressure relief valve: When opening and closing the valve, remove the pressure water between the valve and the sealing cover, so as not to wear the sealing cover;
4, sewage valve: discharge the lower part of the ball shell sewage.
Transmission classification
1, pneumatic ball valve
2. Electric ball valve
3, hydraulic ball valve
4, gas hydraulic ball valve
5, electric hydraulic ball valve
6, turbine drive ball valve
Classification characteristics
Ball valves are: floating ball valve, fixed ball valve, track ball valve, V-type ball valve, tee ball valve, stainless steel ball valve, cast steel ball valve, forged steel ball valve, ash discharging ball valve, anti-sulfur ball valve, pneumatic ball valve, electric ball valve, sleeve ball valve, welding ball valve.
According to the material classification of the shell/main body, the ball valve can be divided into:
1. Metal valve: such as carbon steel valve, alloy steel valve, stainless steel valve, cast iron valve, titanium alloy valve, Monel valve, copper alloy valve, aluminum alloy valve, lead alloy valve.
2. Metal body lining valve: such as rubber lined valve, fluorine lined valve, lead lined valve, plastic lined valve, lined enamel valve.
3. Non-metallic material valve: such as ceramic valve, glass valve, plastic valve.
Domestic production of ball valve manufacturers more, the connection size is mostly not uniform. Mainly divided into the following categories:
The ball valve of the ball is floating, under the pressure of the medium, the ball can produce a certain displacement and pressed on the end of the sealing surface, to ensure that the end of the export seal.
structure
Good sealing, but the ball bearing the working media of all the load to the export sealing ring, so it should be considered whether the sealing ring material can withstand the working load of the ball media, in higher pressure impact, the ball may occur deviation. This structure is generally used for low and medium pressure ball valves.
The ball of the ball valve is fixed and does not move under pressure. Fixed ball and ball valves are equipped with floating seats, which, subject to medium pressure, cause the seat to move so that the sealing ring is pressed tightly on the ball to ensure the sealing. Bearings are usually mounted on the upper and lower shafts of the spheroidal valves, with small operation twist, suitable for high pressure and large diameter valves.
In order to reduce the operating torque of the ball valve and increase the reliability of sealing, and appeared oil sealing ball valve, both in the seal between the injection of special lubricating oil, in order to form a layer of oil film, that is, to enhance the sealing, and reduce the operating torque, more suitable for high pressure large diameter ball valve.
The elastic
The ball valve is ball elastic. Ball and seat sealing ring are made of metal materials, the pressure is very high, depending on the pressure of the medium itself has not reached the requirements of sealing, must apply external force. This valve is suitable for high temperature and high pressure media.
The elastic sphere is obtained by cutting an elastic groove at the bottom of the inner wall of the sphere. When closing the channel, use the stem wedge to inflate the ball and seat to seal. Loosen the wedge before turning the ball, and the ball returns to its original shape, creating a small gap between the ball and the seat to reduce friction on the sealing surface and operating torque.
Qv347, Qv647, Qv947 V regulating ball valves have shear action on the seat due to the ball core with V-shaped structure. Therefore, it is suitable for the control of relevant technological parameters in suspension medium containing fiber or micro solid particles in papermaking, chemical industry, metallurgy and other industrial enterprises. It is especially suitable for the automatic regulation of the fluid of suspended particles such as pulp, white water, black liquid and white liquid in the process of pulping and papermaking and the medium of thick and muddy liquid.
This V-type ball valve belongs to the fixed ball valve, is also a single seat sealed ball valve, regulating performance is the best ball valve, flow characteristics is equal percentage, adjustable ratio up to 100:1. Its V-cut and metal seat between shear action, especially suitable for containing fiber, micro solid particles, slurry and other media
Three-way ball valves are T - and L-shaped. The T shape can make the three orthogonal pipelines connect with each other and cut off the third channel, playing the role of diversion and confluence. L-type can only connect two orthogonal pipelines, and cannot maintain the interconnection of the third pipeline at the same time, and only plays the role of distribution.
