Ball Valve

A ball valve is a valve that uses a ball shaped disk to start and stop flow. Ball valves are one of the simplest valve types, and are made in 1-piece, 2-piece and 3-piece configurations. They tend to be the cheapest valve type and one of the easiest to maintain.

The ball valve is a type of the rotary valve. The disc of the ball valve is the ball, which can rotate 90 degrees around the valve stem so as to fulfill the function of opening and closing the ball valve. The ball valve has the functions of not only cutting off the fluid, but also regulating the fluid. The ball valve can be made with various diameters. Ball valves made of different sealing materials and with various valve body structures can be used for a variety of high pressure, medium pressure, low pressure, high temperature and low temperature conditions. The ball valve has the most wide applications among all kinds of valves.

The types of ball valves
According to the structure of the ball valve, the ball valve can be divided into three kinds: the two- way ball valve, the three-way ball valve and the four-way ball valve. Different kinds of ball valves are used for different conditions to cut off the fluid, adjust the fluid, divert the fluid, change the flow direction of the fluid, etc. The following is the introduction of different ball valves.

The two-way ball valve
The two-way ball valve can be divided into two kinds, the Q41F floating ball valve and the Q47H trunnion mounted ball valve in accordance with the structure. In order to adapt to different media, the strongly corrosive resistant Q41F46 fluorine ball valve, the high temperature resistant Q41M high temperature ball valve, the QB41F jacket insulation ball valve for easily crystallizing media and the wear resistant special valve for spraying the pulverized coal are produced based on the two-way ball valve. Equipped with different regulated actuators, these ball valves can be made into the pneumatic control ball valve and the electric control ball valve for adjusting the medium parameter of the pipeline. Users can choose the appropriate drive mode according to the working conditions. Users can also use electric or pneumatic actuators to have the automatic control of the working condition.

The three-way ball valve
The three-way ball valve has the structure of two spools, the L-type and the T-type spools, which are produced specifically for the three-way pipe. Three-way ball valves are mainly used to divert the fluid, mix the fluid or change the flow direction of the fluid. The L-type three way ball valve can connect the main pipe and the other two vertical pipes respectively, playing the role of diversion. The T-type three way ball valve can make the three pipelines connect with each other so that it can play the role of diversion and fusion. If the T-type three way ball valve are equipped with electric or pneumatic actuators, the working conditions can be automatically controlled.

The four-way ball valve
The four-way ball valve is also called the four-way reversing valve, which is designed specially for the four way pipeline. When the ball is rotated 90 degrees, the way of water supply is switched. The flow directions of the two media can be switched at the same time by the four-way ball valve, and the flow directions of two media being switched at the same time usually needs four sets of valves. Now, just one valve is enough. So the four-way ball valve is convenient and cost-saving. The electric or pneumatic actuator can be used according to the user’s needs so that the user can have the automatic control of the working conditions.

One of the main advantages of ball valves is that they offer a very quick shut off, usually by turning the stem 90º. This is as opposed to gate and globe valves, for example, that require multiple turns to shut-off. For the very same reason, ball valves are not suited for flow-control or throttling, and user would prefer to opt for globe valves for these purposes. Ball valves are often sub-divided into categories that distinguish between the seat material, such as PTFE seated ball valves, which is the most common version or metal-seated ball valves for high-temperature applications.

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Photo courtesy: The Alloy Valve Stockist

Related Pages

External Links & References

  1. What is a ball valves
  2. Wikipedia
  3. Explore the World of Piping
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