How to Prevent Valve Body Getting Rusty
As corrosion phenomenon appears during the spontaneous interaction between metal and the surrounding, how to isolate the metal from the surroundings or to use more non-metal synthetic materials keys of anti-corrosion. The valve corrosion usually is understood as the destruction of metal material caused by chemical or electrochemical environment.
There are two forms of valve body
corrosion, chemical corrosion & electrochemical corrosion. The corrosion rate is decided by media temperature, pressure, chemical performance and corrosion resistance of the valve body material. The corrosion rate can be divided into six grades:
1. Super anti-corrosion : the corrosion rate is lower than 0.001 millimeter/year
2. High anti-corrosion: the corrosion rate is between 0.001~0.01 millimeter/year
3.Anti-corrosion: the corrosion rate is between 0.01 to 0.1 millimeter/year
4. Reasonable anti-corrosion: the corrosion rate is between 0.1 to 1.0 millimeter/year
5.Poor anti-corrosion: the corrosion rate is between 1.0 to 10 millimeter/year
6.Corrosive: the corrosion rate is faster than 10 millimeter/year
Although we can find lots of materials about valve body
anti-corrosive measures, it is still a tough problem for us to select the most appropriate method since corrosion is such a complex problem. So, what measures can we take to prevent the valve body corrosion?
First, select the right material. The difficulty of selecting the materials of valve body is that we should not only consider the corrosion problem but also the voltage and heat endurance capabilities, cost and convenience of purchasing, etc.
Second, take lining measures such as lead lining, aluminium lining, engineering plastic lining, natural rubber lining and all kinds of synthetic rubber lining, etc. This is an economical method If the medium condition meets the requirement.
Third, under the low pressure and temperature condition, using nonmetal as the valve body material will effectively prevent the corrosion. In addition, the surface of valve body will also oxidize in the air and we usually have painting treatment for iron steel materials to prevent them from oxidization.