The ERW casing
is a large diameter pipeline that acts as a fixed oil well and natural gas well or well. The casing is inserted into the borehole and fixed with cement to prevent the borehole from separating the formation from the borehole and ensure drilling mud circulation for drilling.
Different types of casing used in the oil production process: the surface protection wells of the ERW casing are not affected by shallow water and shallow air, support the wellhead equipment and maintain the other layers of the casing. The technology ERW casing separates different levels of pressure to protect normal drilling fluid circulation and production casing. In order to install explosion-proof devices, leak proof devices and tail pipes in boreholes. The oil casing outputs oil and natural gas from the storage layer under the ground. Used for protective wells and stratified drilling mud. In the production of ERW bushing, the outer diameter is usually between 114.3 millimeters and 508 millimeters.
Anticorrosion measures of ERW casing
1. first of all, we should do well the water quality standard and strictly check and manage the water quality. Clean up the dispensing and strengthen the main pipe cleaning work, so that the bottom water quality of the station is up to standard, and the introduction of the corrosion source in the annular space is reduced.
2. put into operation the new injection well, adopt the sterilized environmental protection liquid, and form the system.
3. as mechanical wear accelerates the corrosion of the casing, it is suggested to add a rubber ring at the tubing joint or add a centralizer to the serious part of the well so as to avoid damage to the tubing during the tubing process. During operation and water injection. One side contact sleeve;
4. in the case of serious bacterial corrosion and slow growth of high temperature SRB, it can periodically injecting high temperature ring water or water vapor at 100 degrees Celsius to kill the scale of SRB.
5. it is not advisable to recommend cathodic protection and coated bushing before the corrosion of the casing in the injection well is effectively controlled.