Leakage is one of the main factors causing accidents, so it is very important to improve the leakage prevention ability of Dalian marine valves. In fact, to prevent valve leakage, it is necessary to master the basic knowledge of preventing medium leakage at all sealing parts of the valve - valve sealing, which is the most important.

There are many factors affecting valve sealing, mainly including the following:

1. Sealing sub structure

Under the change of temperature or sealing force, the structure of the sealing pair will change. Moreover, this change will affect and change the force between the sealing pairs, thus reducing the performance of the valve seal.

Therefore, when selecting seals, it is necessary to select seals with elastic deformation. At the same time, pay attention to the width of the sealing surface. The reason is that the contact surface of the sealing pair cannot be completely matched. When the width of the sealing surface increases, the force required for sealing shall be increased.

2. Specific pressure of sealing surface

The specific pressure of the sealing surface affects the sealing performance and service life of the valve.

Therefore, the specific pressure of the sealing surface is also a very important factor. Under the same conditions, the valve will be damaged if the specific pressure is too high, but the valve will leak if the specific pressure is too low. Therefore, we need to fully consider the suitability of specific pressure in design.

3. Physical properties of medium

The physical properties of the medium also affect the sealing performance of the valve. These physical properties include temperature, viscosity and surface hydrophilicity.

The temperature change not only affects the relaxation of the sealing pair and the change of the part size, but also has an inseparable relationship with the gas viscosity. The gas viscosity increases or decreases as the temperature increases or decreases.

Therefore, in order to reduce the influence of temperature on the sealing performance of the valve, when we design the sealing pair, we should design it as a valve with thermal compensation such as elastic valve seat.

4. Quality of sealing pair

The quality of sealing pair mainly refers to the selection, matching and manufacturing accuracy of materials. For example, the sealing surface of the valve disc and the valve seat is very consistent, which can improve the sealing performance. Its labyrinth sealing performance is good because of its high circumferential waviness.

Valve leakage is very common in life and production. It may cause waste or bring danger to life. For example, leakage of tap water valve may lead to serious consequences, such as toxic, harmful, flammable, explosive and corrosive medium leakage in the chemical industry, which may seriously threaten personal safety, property safety and environmental pollution.