The general chemical heat treatment of ERW casings, such as carburizing, carbonitriding, and carbonitriding, is an additional multi-parameter heat treatment of one-component, two-component, and three-component, respectively.


In recent years, a number of new technologies using ERW casing chemical heat treatment, such as vacuum chemical heat treatment, fluidized bed chemical heat treatment, ion permeation metal, ion implantation, laser surface alloying, etc., have been developed to improve the wear loss of ERW casing. . Corrosion resistance and other properties. The application of rare earth in chemical heat treatment (ie, infiltration with rare earth) can significantly improve the water seepage rate, shorten the treatment cycle, and improve the wear resistance and corrosion resistance of the layer, which is a major feature of China.


In addition, ERW casing solid solution chemical heat treatment is also a notable trend. Huang Jianhong of Inner Mongolia Agricultural Machinery Research Institute has developed a nitrogen martensite treatment (N*M treatment) process, which has been successfully applied to the production of E. RW housing. The ERW casing is used to support the oil and gas well wall to ensure the normal operation of the entire well after the drilling process. Each well is a multi-layer casing according to different drilling depths and geological conditions. After the casing is cemented, it is different from the oil pipe and the drill pipe and cannot be reused. It is a one-time material consumption. As a result, casing consumption accounts for more than 70% of all wells. Casing can be divided into: duct, surface casing, and technical casing according to the application.