Ball valve is currently the most widely used mechanical product in all valve markets. It is mainly composed of valve body, valve seat, ball, stem and transmission device, which is driven by the actuator to rotate the ball core to achieve the function of switching or regulating. There are many kinds of ball valves, through the structure, connection, pressure level, drive form, etc., can be combined into a variety of different functions of the product. To select the right type of valve for your application, it helps to understand what a ball valve is and the differences between the key types: full port or standard port ball valves.
What is Full Port(Full Bore) Ball Valve?
Full port ball valve, also named full bore ball valve, has a straight flow path. It has equal width flow channel, which is from the flow into the outflow of the orifice size is the same. The size can not be less than the value of the standard provisions, roughly equivalent to the nominal diameter of the specification, such as DN50 full bore ball valve flow channel diameter also need to be about 50. In addition, it has no restriction of flow from the original pipe diameter. Most full port ball valves are two-way ball valves. In short, when the inner diameter of the ball valve is larger than 95% of the inner diameter of the ball valve port, it is called full port ball valve.
Full port valves are usually more expensive than standard and reduced port valves, but they offer better flow rates and less potential for prohibitive chemical buildup along internal edges. Full port valves also minimize the chance for cavitation.
Features of Full Port Ball Valves
1)Low flow resistance(high flow coefficient), about the same as a straight piece of pipe.
2)Very little pressure drop across the valve.
3)More material required to make the valve body and the rotatable ball inside it.
Full bore ball valve is generally used for conveying viscous, easy slagging media pipeline because of its small fluid resistance. It is basically no flow resistance, facilitating the regular scraping wax blowers through.
Regardless of the medium conveyed, full-pass ball valve must be used for the pipeline that needs to be cleared periodically. As the ideal type of pipeline control products, their medium will not reduce the flow through the full bore ball valve, and the flow resistance is small, especially the strict requirements of the working conditions, especially in the oil pipeline and gas pipeline in the main line to be buried in the ground, must use full bore welded ball valve.
What is a Standard Port Ball Valve?
A standard port ball valve is about the same diameter as the pipe or tube coming into and exiting it. The working part of the valve is the rotatable ball inside the valve body. Since the working part of the valve fits inside the valve body, the bore through the valve ball is smaller than the diameter of the valve’s connecting pipe or tube.
The Standard Port Ball Valve
Features of Standard Port Ball Valves
1)High flow resistance(low flow coefficient), narrower than the pipe across section.
2)Flow restriction produces a pressure drop. Flow creates a pressure difference across a valve. Rapid pressure drop across a valve can cause cavitation. Cavitation is the rapid formation and collapse of vapor bubbles within a liquid. When this happen, the collapse of these vapor bubbles could erode the valve and pipe around them.
3)Less material required to make the valve body and the rotatable ball inside it.
The Standard Port Valve Design
A standard port also has a straight flow path, but there is a flow restriction that produces a pressure drop as the flow passes through the valve. Basically, the valve inlet and outlet connections are the same sizes as the tubing or pipe. But the interior component (the ball), which fits within the valve, has a smaller bore (hole) than the pipe or tube. Therefore it produces the pressure drop due to the flow restriction. In other words, standard port valves have smaller interior diameters than full port valves. As long as a moderate pressure drop and slight flow turbulence are acceptable in your system, standard port ball valves are recommended.
In fact, changes in flow rate are normal in most piping systems. Length of pipe sections, bends in the system or system conditions affect the flow rate enough that a standard port valve will not be the most influential factor. In the vast majority of applications.