Oil casing detection method:
1. Ultrasonic testing: When ultrasonic waves are transmitted in the tested material, the acoustic properties of the material and changes in the internal structure will have a certain impact on the propagation of the ultrasonic wave. By detecting the degree and condition of the ultrasonic wave, we can understand the changes in the function and structure of the material.
2. Radiographic detection: Radiographic detection uses the difference in the amount of radiation transmitted through the normal part and the defect to form the resolution of the blackness on the film.
3. Penetration testing: Penetration testing is to use the capillary action of the liquid to penetrate the penetrating liquid into the open defect on the surface of the solid raw material, and then suck the penetrating liquid to the surface through the imaging agent to reveal the existence of the defect. Penetration testing is suitable for various metal and ceramic workpieces, and the time from penetration application to defect appearance is relatively short, usually about half an hour. It can detect surface fatigue, stress corrosion, and welding cracks, and can directly measure the size of cracks.
4. Magnetic particle testing: Magnetic particle testing uses magnetic flux leakage at defects to absorb magnetic powder and form magnetic marks to provide defect display. It can detect surface and sub-surface defects, and the nature of defects is easy to distinguish. Paint and electroplating surfaces will not affect the accuracy of detection.
Anti-corrosion countermeasures for oil casing
1. First of all, do a good job in meeting water quality standards, and strictly monitor and manage water quality. Carry out cleaning and separate injection, strengthen the cleaning of the main water pipeline, ensure that the water quality in the station and the bottom of the well meets the standard, and reduce the introduction of corrosion sources into the annular space;
2. For the water injection wells that have been newly put into production, the annulus protection fluid, which is mainly sterilized, is adopted, and a system is formed to add it regularly;
3. Given the accelerated effect of mechanical abrasion on the corrosion of oil casing, it is recommended to add a rubber ring on the tubing coupling or add a centralizer to the serious part of the well deviation, to avoid the tubing scratching the casing and one side contacting the casing during operation and water injection;
4. Given the serious corrosion of sub-scale bacteria and the slow growth and killing of SRB at high temperatures, high-temperature water or steam at 100 degrees Celsius can be injected into the annular space regularly to kill the sub-scale SRB;
5. It is not recommended to promote the use of cathodic protection and coated casing before the corrosion in the casing of the water injection well is effectively controlled.
Post time: Jul-24-2023