Petroleum casing is a kind of large-diameter pipe, which plays a role in fixing oil and natural gas well walls or boreholes. The casing is inserted into the well hole and fixed with cement to prevent the well bore from collapsing between the rock strata and the well bore, and to ensure the circulation of the drilling mud to facilitate drilling and exploitation. Different types of oil casing used in the process of oil extraction:
1. Surface oil casing
- Protect the well to avoid contamination by shallow water and gas layers,
- Support wellhead equipment and maintain the weight of other layers of casing.
2.Technical oil casing
- Separate the pressure at different levels so that the drilling fluid can circulate normally and protect the production casing.
- In order to install anti-burst devices, leak-proof devices and liners in the well.
3. Oil layer oil casing
-Export oil and natural gas from the reservoir below the surface.
-Used to protect wells and layer drilling mud.
When petroleum casing is produced, the outer diameter is usually 114.3 mm to 508 mm.https://www.permanentsteel.com/productshow/casing-pipe.html