① Floating Ball – Fixed Ball Type
This type features a spherical ball. In the floating-ball design, only the upper surface of the ball is fixed by the valve stem, while the ball itself is held in position by the pre-tightening force and the medium pressure before output. The pressure is completely borne by the valve outlet end and the ball, resulting in a high sealing surface strength.
In the fixed-ball design, both the upper and lower surfaces of the ball are fixed by the valve stems, with the ball connected to the upper and lower rods as one unit. This structure requires a smaller operating torque and is suitable for high-pressure and large-diameter valves. It is structurally complex and features a floating valve seat design.
② Side-Entry Type
In this type of ball valve, the ball and other internal components are inserted into the valve body from the side. The one-piece design is compact and lightweight, commonly used for small-diameter cast steel valves with non-metallic floating ball seats.
The two-piece structure is easier to machine and manufacture, offering a wide variety of models — it is the most common product type. The valve body length is increased and is composed of two parts connected by bolts and nuts.
③ Top-Entry Ball Valve
In this type, the internal components are loaded from the top of the valve. It is usually made by casting and features a solid structure, suitable for medium- and large-diameter valves of various pressure grades, typically designed as a three-body type.
Its main advantage is that maintenance can be performed without removing the valve from the pipeline — internal parts can be replaced or repaired online. However, the central cavity is large, the structural length is long, and the overall weight is heavy.
④ Fully Welded Type
The valve body is formed by fully welding plates or pipes, with an internal structure similar to that of a three-piece ball valve. It has no external leakage points, a symmetric design, and strong resistance to pipeline stress, making it ideal for long-distance pipelines.
It is mainly used for buried pipelines or oil and natural gas pipelines under harsh conditions. The internal components are protected from atmospheric corrosion and have a long service life. However, the internal parts cannot be replaced or repaired, and the cost is relatively high.
Ball Valve Lock