How To Prevent Corrosion Of Oil Casing?

How to maintain oil casing?
Oil casing is one of the important equipment for oil exploration, development and production. It is used as a connecting piece between the well wall and the oil pipe to fix the oil pipe and seal the wellbore to ensure normal production of the oil field. Therefore, the maintenance of oil casing is very important. Here are some common methods and considerations.
During the use of oil casing, the surface and interior of the casing need to be cleaned regularly to prevent accumulation and impurities from affecting work efficiency, and to check for corrosion or damage. When cleaning, be sure to use soft brushes and other tools. Do not use wire brushes or hard objects to wipe to avoid scratching the surface of the casing.
In order to resist corrosion and erosion of oil casings from the external environment, the surface can be protected by coating. Commonly used protective coatings include epoxy resin, asphalt, etc., which can effectively prevent casings from being corroded in various harsh environments.
Oil casing must be kept dry during storage and use to avoid corrosion and other problems. For oil casings stored for a long time, they should be prevented from being exposed to high humidity environments for a long time, and their status should be checked regularly to ensure that they can be repaired and replaced in time when necessary.
How to prevent corrosion of oil casing?
1. First, do a good job in meeting water quality standards and strictly monitor and manage water quality. Carry out cleaning and injection, strengthen main water pipeline cleaning, ensure that the water quality in the station and at the bottom of the well reaches standards, and reduce corrosion sources from entering the annular space;
2. For newly put into production water injection wells, use annular protection fluid mainly based on sterilization, and establish a system to add it regularly;
3. In view of the accelerated effect of mechanical wear on oil and casing corrosion, it is recommended to add rubber rings to the oil pipe couplings or add centralizers to areas with serious well deviations to avoid oil pipes from scratching the casing and casing during operations and water injection. One side is in contact with the shell;
4. In view of the serious corrosion of scale bacteria and the slow growth and killing of SRB at high temperatures, high-temperature water or steam of 100 degrees Celsius can be regularly injected into the annular space to kill scale SRB.
5. Before the corrosion of water injection well casing is effectively controlled, it is not recommended to promote the use of cathodic protection and coated casing.