1、 Internal anti-corrosion of valves

The anti-corrosion of valves mainly focuses on the contact surface between the valve cavity and the medium, to prevent the medium from causing corrosion inside the valve. The main anti-corrosion measures include:

Select materials based on the characteristics of the medium: Choose appropriate valve materials based on the characteristics of the medium that the valve is in contact with, such as corrosiveness, temperature, pressure, etc. For example, for highly corrosive media, corrosion-resistant materials such as stainless steel and alloy steel can be selected.

Coating protection: Apply anti-corrosion paint to the valve cavity to form a protective film that isolates the medium from direct contact with the valve cavity. The selection of anti-corrosion paint should be determined based on the characteristics of the medium and the usage environment.

Optimization design: Reasonable valve structure design and processing technology can reduce the occurrence of corrosion. For example, avoiding stress concentration and reducing design details such as welding joints can reduce the risk of corrosion.

2、 External anti-corrosion of valves

The external anti-corrosion of valves mainly focuses on the anti-corrosion of the valve shell and connecting components to prevent external environment from corroding the valve. The main anti-corrosion measures include:

Surface cleaning and treatment:

Mechanical rust removal: Use tools such as sandpaper and wire brushes to clean the surface of the valve, removing rust and dirt.

Sandblasting treatment: High speed abrasive is sprayed onto the surface of the valve through compressed air to remove surface dirt and oxide layer, improve surface roughness and adhesion. Coating protection: Spray anti-corrosion paint: Spray a layer of anti-corrosion paint on the surface of the valve to form a protective film, isolating the valve body from contact with oxygen and moisture in the air. The selection of anti-corrosion paint should be determined based on the material, operating environment, and anti-corrosion requirements of the valve.

Spray coating: Plastic powder is evenly sprayed onto the metal surface of the valve through a spray gun, and then baked at high temperature to melt, level, and solidify the plastic powder, forming a dense coating. Electroplating: Electroplating a layer of corrosion-resistant metal, such as chrome or nickel plating, on the surface of the valve to enhance its corrosion resistance.

Additional protective layer: Install protective sleeves: Install plastic sleeves, rubber sleeves, and other protective sleeves on the outside of the valve to isolate the valve body from direct contact with the external environment. Wrap anti-corrosion tape: Wrap a layer of anti-corrosion tape on the surface of the valve, such as polyethylene anti-corrosion tape, glass ribbon, etc., to form a protective layer.

Electrochemical protection:

Anodic protection: By applying an anodic current to the protected metal, a passivation film is formed on its surface to prevent corrosion reactions from occurring.

Cathodic protection: By applying an external current, the valve becomes the cathode of the corrosive battery, thereby avoiding corrosion. This method is particularly suitable for valves used underground or underwater.

Regular maintenance: Regularly inspect and repair valves to check for corrosion, wear, and other issues, and promptly address them. At the same time, regularly clean the dirt and corrosion products on the surface of the valve to maintain its cleanliness and smoothness.

Environmental control: Whenever possible, slow down the corrosion process by controlling factors such as temperature, humidity, and oxygen concentration in the environment where the valve is located. For example, adopting open factory buildings or ventilation cooling measures to reduce environmental temperature and humidity.