Corrosion and Wear Resistant Valves
Different kinds and specifications of valves are used on the pipelines of acids, alkalis, salts, oils, and waters. In order to solve the corrosion problems, materials such as rubber, plastic, stainless steel, and titanium alloys are generally used. The use effect in the condition is not ideal, and the lining rubber and the lining plastic protective layer are easy to cause the problem of layering and falling off during use. Stainless steel and titanium alloy valves have limited wear resistance and are expensive and costly. Therefore, we have developed coated valves, which have the following characteristics:
1. The bond strength between the coating and the steel is as high as 90 MPa, which is not achieved by the lining and lining, and solves the delamination problem.
2. The over-flow part adopts the overall protection method to solve the problem of joint leakage and corrosion.
3. The coating can be machined to meet the dimensional accuracy requirements of the components.
4. The coating is resistant to acids, alkalis, salts and other media. Common carbon steel can be used as a valve substrate instead of stainless steel or titanium alloy, reducing equipment investment.
The mechanical properties and chemical resistance of various types of coatings are listed in the following two tables.
The mechanical properties of antiseptic series coated coating
|Performance||Unit||Test results of various models||Execution standard|
|Shear strength||MPa||43||43||43||45||43||ASTM D1002-72(83)|
|Impact strength||J||18||18||12||19||12||ASTM G14-77|
|Wear resistance||L/μm||＞3||＞3.5||＞3||＞3||＞3||ASTM D968-81|
Chemical corrosion resistance of a series coated coatings
|Sodium chloride solution||Saturation||○||○||○||○||○||○||○||○||○||○||○|
|Sodium chloride solution||3.5||○||○||○||○||○||○||○||○||○||○||○|
|Sodium hydroxide solution||10||○||○||○||○||○||○||○||○||○||×||×|
|Sodium sulfate solution||30||○||○||○||○||○||○||○||○||○||○||○|
|Sodium carbonate solution||Saturation||○||○||○||○||○||○||○||○||○||○||○|
|Sodium nitrate solution||Saturation||○||○||○||○||○||○||○||○||○||○||○|
|Sodium hypochlorite solution||25||○||○||○|
|Salt spray resistance
|After 1000 hours of continuous testing, the film is in good condition, with no blistering, cracking, and peeling.
It is the best grade for salt spray resistance.
Note: "○" indicates excellent coating performance, "△" indicates good coating performance, "×" indicates poor coating performance, and chemical corrosion resistance is determined according to GB/T 6554-2.14-86 national standard.