Sanitary Valve due to its corrosion resistance, high strength, long life, safety, hygiene, and beauty, it is currently widely used in building water supply and direct drinking water pipelines, and many decorations also use stainless steel pipes. Corrosion resistance is the primary performance of stainless steel and stainless steel pipes over other steel types. According to modern knowledge, stainless steel can only remain rust-free or corrosion-resistant in an unpolluted atmospheric environment. In more than a dozen applications, especially in many industrial application environments, stainless steel can still corrode due to the erosion of corrosive media.

The corrosion resistance of stainless steel depends on the chemical composition, surface state and environmental conditions of the steel. In specific application conditions, that is, after the steel type and environmental conditions are determined, the formation of a uniform and dense passivation film on a clean and smooth surface is the prerequisite for ensuring its corrosion resistance, and local damage to the passivation film is the root cause of local corrosion. Stainless steel is not absolutely rust-free steel. Its good corrosion resistance is only relative and conditional. It is particularly important to keep its surface clean, that is, in a passivation state.

Characteristics of the formation of the passive film: Under high temperature conditions, the surface of stainless steel will form an oxide scale with extremely high adhesion, the main component of which is Cr2O3. However, the passive film formed on the surface of stainless steel at room temperature is not a true oxide film, and its physical and chemical structure has not yet been fully confirmed. It is currently often called an oxide or hydroxide film. Normal temperature, purification and aerobic environment are three important concepts or elements for the formation of the passive film. When stainless steel pipes and all stainless steel products are delivered, great attention should be paid to purification or passivation treatment, the purpose of which is to form a purified film on their surface to ensure their corrosion resistance.