Oil casingthe historical development

After more than 20 years of efforts, China's oil well pipe production from scratch, from low price to high price, from low steel to API series products to special needs of non-API products. It is close to the level of foreign oil well pipe products in quantity and quality.Oil casingThe domestic market share has exceeded 80% and has been a net export product for many years.

In 2011, China's crude oil production reached 0.204 billion tons, an increase of 0.32 percent over the same period in 2010. Natural gas production reached a record high of 102.531 billion cubic meters, up 6.9 percent year-on-year. China is still in the stage of rapid urbanization and industrialization, and oil demand is expected to grow at an average annual rate of about 4% in the next few years. The increase in demand for oil has contributed to the increase in demand for oil drilling equipment.

From the regional distribution of our country,Oil casingThe demand is no longer concentrated in the eastern region. From the perspective of the development trend of domestic oil and gas fields, from the initial development of the eastern Daqing, Liaohe and Shengli oilfields to the later development of the western Sichuan and Xinjiang oilfields, the development trend of offshore oilfields will also be developed from land to beach and from shallow to deep. In addition, the drilling depth is getting deeper and deeper, the drilling conditions are becoming more and more complex, and the requirements for oil casing are getting higher and higher.

　　Oil casingAnti-corrosion measures

First of all, do a good job in water quality standards, strict water quality testing and management. Carry out cleaning and separate injection, strengthen the cleaning of the main water pipe, ensure the water quality in the station and at the bottom of the well, and reduce the corrosion source into the annulus;

2. For the newly put into operation of the injection well, the annular protection liquid mainly for sterilization should be added, and a regular addition system should be formed;

3. In view of the accelerating effect of mechanical wear on the corrosion of the oil casing, it is recommended to install a rubber ring or centralizer on the tubing coupling at the location with serious well deviation to avoid scratching the casing and contacting one side of the casing during operation and water injection.

4. In view of the serious bacterial corrosion under scale, SRB grows slowly at high temperature, and high temperature water or steam at 100 ℃ can be injected into the annulus regularly to kill SRB under scale.

5. It is not recommended to promote the use of cathodic protection and coated casing before the casing corrosion of water injection wells is not effectively controlled. (1) Domestic casing model is SY/T6194-96. The length of the casing is variable, and its range is 8-13m. However, bushings of not less than 6m may be provided, and the number of bushings shall not exceed 20%.

(2) There shall be no folding, streak, separation, cracking, rolling and scars on the inner and outer surfaces of the casing. These defects shall be removed to a depth not exceeding 12.5 percent of the nominal wall thickness.

(3) There shall be no folding, wool, separation, crack, rolling, scarring and other defects on the outer surface of the collar.

(4) Thread surfaces of casing and coupling shall be smooth, and there shall be no burrs, tears and other defects that may cause thread interruption and affect strength and tight connection.