Casing is used for a variety of applications including oil and gas well drilling, extracting oil and gas from reservoirs, etc. Our casing services allow us to offer the best solutions for each customer’s particular well conditions.According to the using ,we can divided the casing to four different kinds,they are tube,surface casing ,technical casing and oil layer casing.
First one is tube.Mainly used in ocean drilling or the desert, to separate water and sand and ensure the smooth drilling. The main specifications of this casing are: ∮762mm(30in) ×25.4mm, ∮762mm(30in) ×19.06mm.
The second one is Surface casing: It is mainly used for the first time to drill, drill the soft ground to the bedrock. In order to ensure this part of the formation does not collapse, oil surface casing should be adopt. The main specifications of this casing are: 508mm(20in), 406.4mm(16in), 339.73mm(13-3/8in), 273.05mm(10-3/4in), 244.48mm(9-5/8in). Depth of the casing pipe depends on the depth of the soft ground, generally 80~1500m. Its external pressure and internal pressure are not large, generally use K55 steel or N80 steel grade.
The third one is Technical casing: It used in the process of complex drilling. When encountered the collapse layer, the oil layer, gas layer, the layer of the water layer, the leakage layer and the salt gypsum layer, the technical casing is needed to be sealed, otherwise the drilling can not be carried out. Some well formation is deep and complex, and the depth has several kilometers. This deep well needs several layers of casing, which mechanical properties and sealing performance requirements are very high. The main specifications of the technical casing are: 339.73mm(13-3/8in), 273.05mm(10-3/4in), 244.48mm(9-5/8in), 219.08mm(8-5/8in), 193.68mm(7- 5/8in) , 177.8mm(7in).
The last one is Oil layer casing: When drilling to the objective layer, casing need to sealed the oil and gas and the internal of casing is tubing. The main specifications of the oil layer casing are: 177.8mm(7in), 168.28mm(6-5/8in), 139.7mm(5-1/2in), 127mm(5in), 114.3mm(4-1/2in)