Surface Ball tube has a hard surface, so in this case, we should talk about a soft seal, which is being constantly under load springs, rubs the surface of the tube and has heavy wear. This leads to a reduction in the life of the crane. 3) simplicity of design. Ball valves with a floating plug is really structurally simple and fairly pushed the valve in the category of small valve passages, but they require more effort in the management and, with increasing passage is more complex and more expensive for the necessary control of the drive.
Cranes with a cork on the supports, are the most compact type of fixtures in its class, but the complexity of the design are at the level of slide gate valves. 4) High performance. Indeed all the taps, and not just ball, require the opening turn at an angle of 90 degrees. This distinguishes them from other types of valves. 5) Easy to install and operation. As for installation, it is no different from other types of mounting fixtures. Ease of use is the lack of cranes in their construction of the spindle seal packings. Gland requires periodic compression, but it thus allows to restore integrity and the spindle with minimal time.
In this case, the crane requires disassembly and replacement of seals or O-ring. Here it is appropriate recall group valves with non-rising stem, sealing, which is similar stem seal ball valve. 6) Low maintenance cost at work.