Classification and anti-corrosion of oil casing

Oil casing can be roughly divided into the following categories according to different usage methods:
1. Surface casing.
2. Intermediate casing.
3. Production casing.
4. Drilling casing.
Surface casing mainly refers to hanging and supporting subsequent layers of the casing through the casing head installed at the top. Another is to isolate the shallow water layer on the surface from the complex strata in front to protect the drilling from the pollution of the shallow water layer. Intermediate casing or technical casing is used to isolate the layers with different formation pressures or complex strata that are prone to collapse and leakage. Production casing is used to protect the production layer and provide a channel for transporting oil and gas from the production layer to the ground. Drilling liner is used to reduce the load of the drilling rig and the load after casing during and after cementing, saving casing and cement and reducing the cost of cementing. In the use of industries and fields, oil casing has shown important roles and good performance.

The anti-corrosion of oil casing is mainly divided into:
1. Apply anti-corrosion coating on the outer wall.
2. Apply anti-corrosion coating on the inner wall.
3. Apply anti-corrosion and cooling coating.
With the use of oil casing in harsh oil extraction industries such as polar regions and oceans, the material and structure of the oil casing must have good node properties, excellent physical properties, stable chemical properties, and a wide temperature adaptability range. If the oil casing cannot do this, it should be coated with an anti-corrosion coating to help it cope with the harsh use environment. Applying a coating on the outer wall is used to reduce external erosion. The anti-corrosion coating on the inner wall reduces friction, reduces corrosion in the pipe, and increases the amount of oil delivered. The anti-corrosion and thermal insulation coating is used to transport crude oil and fuel oil and reduce the heat dissipated from the pipeline to the soil.