Maintenance Of Stainless Steel Ball Valves

Stainless steel ball valves are easy to contact with other metal and iron products during the manufacturing process. In order to keep stainless steel valves rust-free, the easiest way is to follow the following process.

First: after the blank is finished, after pickling, it must be rinsed, if there are sand holes or perforations, it should be gas-shielded welded by argon arc welding. Then polish and then carry out solid melt treatment;
Second: the finished product, after the completion of the processing and pressure test. It should be rinsed with water with anti-rust powder.
Third: try to use wooden boxes and packaging during transportation, and do not touch metal products.
Fourth: After installing the pipeline, it should be regularly maintained and maintained, such as lubricating oil on the valve stem. Open and close the valve several times appropriately. It makes the ball, valve stem, and sealing surface not easy to assimilate.

Stainless steel ball valves generally have two structures: reduced diameter and non-reduced diameter channel. Regardless of the structure, the flow resistance coefficient of the ball valve is relatively small.

In particular, the so-called full-flow type, that is, the ball valve with no reduced diameter, because its channel diameter is equal to the inner diameter of the pipeline, the local resistance loss is only the frictional resistance of the same length of pipeline, that is, among all valves, the flow resistance of this ball valve is the smallest. In the rocket launch and its test system, the less resistance the transmission pipe is required, the better.

There are two ways to reduce the resistance of the piping system: one is to reduce the fluid flow rate, for which the pipe diameter and valve diameter need to be increased, which often has a negative impact on the economy of the piping system, especially for the cryogenic delivery system (liquid hydrogen).

(1) Reduce the local resistance of the valve, therefore, the ball valve naturally becomes the best choice.

(2) The opening and closing of the ball valve is fast and convenient.
Since the ball valve only needs to turn 90° to complete the full opening or closing action under normal circumstances, it is easy to achieve fast opening and closing. It can realize fast opening and closing, and the opening and closing time of some structures is only 0.05~0.1s, so as to ensure that it can be used in the automation system of the test bench. When the valve is opened and closed quickly, the operation is shock-free.

(3) The ball valve has good sealing performance.
The seat of most ball valves is made of elastic materials such as PTFE, and the sealing pair composed of metal and non-metallic materials is commonly called soft seal. Generally speaking, the tightness of soft seals is easy to guarantee, and the processing accuracy and surface roughness of the sealing surface are not very high.

(4) The ball valve has a long service life.
Due to the good self-lubrication of PTFE, the friction and wear with the ball are small, and due to the improvement of the ball processing technology, the roughness is reduced, so as to improve the service life of the ball valve.