Stainless steel ball valve in the manufacturing process, easy to contact with other metal iron products.In order to make the stainless steel valve can not rust, the simplest way is to do according to the following process.

First: after the blank finished product, pickling, must be washed clean, if there is a hole or perforation, should use argon arc welding on the gas protection welding.And then grinding, and then solid melting treatment;

Second: finished products, processing after the completion of pressure testing.It should be rinsed with water added with antirust powder.

Third: in the process of transportation, try to use wooden box packaging, do not contact metal products.

Fourth: after the installation of the pipeline, regular maintenance and maintenance of it, such as the valve stem often coated with lubricating oil.Open and close valve appropriately several times.Make inside ball, valve stem, sealing surface not easy assimilation.

Stainless steel ball valve generally has two kinds of structure: reducing diameter and non-reducing diameter channel.No matter what kind of structure, the flow resistance coefficient of ball valve is relatively small.

In particular, the so-called full flow type, that is, not reducing the diameter of the ball valve, because its channel diameter is equal to the inside diameter of the pipe, the local resistance loss is only the same length of the pipe friction resistance, that is, in all valves, this ball valve flow resistance is the least.In the rocket launch and test system, the resistance of the pipeline should be as small as possible.

There are two ways to reduce the resistance of the pipeline system: one is to reduce the flow rate of the fluid, so it is necessary to increase the diameter of the pipe and the size of the valve, which often has a negative impact on the economy of the pipeline system, especially on the low temperature delivery system (liquid hydrogen) is extremely adverse.

(1) reduce the local resistance of the valve, so the ball valve is naturally the best choice.

(2) Ball valve opening and closing switch is quick and convenient.

Because the ball valve in general circumstances only need to turn the handle 90° to complete the full opening or closing action, 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 bed.When the valve is opened and closed quickly, the operation has no impact.

(3) Ball valve sealing performance is good.

The seat of the vast majority of ball valve is made of ptfe and other elastic materials, metal and non-metallic materials composed of sealing pair, usually called soft seal.Generally speaking, the sealing of soft seal is easy to ensure, and the processing accuracy of the sealing surface and surface roughness requirements are not very high.

(4) Long service life of ball valve.

Because teflon has good self-lubrication, the friction and wear of the ball is small, and because of the improvement of the ball processing technology, the roughness is reduced, so as to improve the service life of the ball valve.