304 stainless steel
seamless pipe to prevent pitting corrosion method
① Avoid a halogen ion concentration.
② Ensure uniformity of oxygen or an oxidizing solution, and the solution was stirred to avoid the liquid is not flowing to small areas.
③ Increase the concentration of oxygen or to oxygen.
④ Increase the pH value. Compared with neutral or acid chlorides, pitting apparent alkaline chloride solution resulting in fewer, or no (hydroxide ions act as anti-corrosion agent).
⑤ Work at the lowest possible temperature.
⑥ Added passivating agent in corrosive media. Low concentrations of nitrate or chromate is valid (preferentially inhibiting ion adsorption on the metal surface, thereby preventing corrosion caused by chloride ion adsorption) in many media.
⑦ Cathodic corrosion protection. There is evidence that use of low-carbon steel, aluminum or zinc electrowinning corner stainless steel combination cathodic protection in seawater will not cause pitting.
Molybdenum 2% -4% 304 stainless steel seamless pipe having good resistance to pitting corrosion. 304 stainless steel seamless pipe containing molybdenum can significantly reduce pitting or general corrosion, corrosive media such as sodium hydride, sea water, sulfurous acid, sulfuric acid, phosphoric acid and formic acid.
