Study on corrosion resistance of inner coating tubing in sour gas environment
Wu Guiyang1，2，3，Zhang qiang1，2，3，Liu Zhide1，2，3
1. Research Institute of Natural Gas Technology， Petrochina Southwest Oil ＆ Gasfield Company， Chengdu 610213， Sichuan， China；
2. National Energy R＆D Center of High Sulfur Gas Exploitation， Chengdu 610213， Sichuan， China；
3. High Sulfur Gas Exploitation Pilot Test Center， CNPC， Chengdu 610213， Sichuan， China
Abstract: Abstract：A method of evaluating corrosion resistance of inner coated tubing in sour gas field was established， and the penetration resistance of inner coated tubing in chloride， hydrogen， gas condensate and H2S／CO2 environments was studied， then the corrosion resistance of inner coated tubing under high temperature， high pressure and high sour gas environment was studied. Supporting related indicators could be used to guide the application of inner coated tubing. The results showed that the phenolic epoxy inner coated tubing had better resistance to penetration， meanwhile， the resistance to penetration of the coating did not change under sour gas environment. With the increase of the temperature and partial pressure of hydrogen sulfide， the coating failure shifted from cathodic peeling to blister.