Surface casing1、Used to seal the upper unstable loose, collapse-prone and leaky formations and water layers.2、Installation of wellhead device to control well blowout.3、Support part of the weight of technical casing and oil layer casing. The depth of the surface casing down depends on the specific situation, usually a few dozen meters to a few hundred meters or deeper (30 to 1500m). The cement return height outside the tubing is usually returned to the surface. When drilling high-pressure gas wells, if the upper rock layer is loose and broken, the surface casing needs to be lowered to prevent the high-pressure gas from escaping the surface. If the surface casing needs to be […]

Petroleum casing emerged not only for oil extraction but also as a pipeline for transporting raw materials. In order to strengthen the quality of petroleum casing, every link in the production process is particularly important, especially the temperature control during the period, which must be mastered in strict accordance with the regulations. Usually, the petroleum casing is quenched by sub-temperature quenching method instead of the ordinary quenching method, because the ordinary quenching method adopted will allow a large amount of residual stress inside the workpiece, thus expanding the brittleness, and the subsequent processing is not so convenient. The sub-temperature quenching is to prevent the brittleness of the oil casing from […]

Different types of casing used in the oil recovery process: surface oil casing – protects the drilling well from contamination by shallow water and gas formations, – supports the wellhead equipment and maintains the weight of other layers of the casing. Technical casing – separates the pressure in the different layers to allow proper flow of drilling fluid levels and to protect the production casing. – To allow for the installation of anti-fracture devices, leak prevention devices and tail pipes in the drilled well. Oil Formation Casing – To move oil and gas out of the reservoir below the surface. – Used to protect drilling wells by layering the drilling […]

Oil casing is a steel pipe used to support the well wall of oil and gas wells to ensure that the drilling process is carried out and that the entire well operates normally after completion. Several layers of casing are used in each well according to different drilling depths and geological conditions. The casing is cemented after the well is drilled, and unlike tubing and drill pipe, it is not reusable and is a one-time consumable material. Therefore, the consumption of casing accounts for more than 70 percent of all oil well tubing. Casing can be divided into: conduit, surface casing, technical casing and oil layer casing according to usage. […]

When the well is drilled to the destination layer (oil and gas-bearing layer), the oil layer casing is needed to seal the oil and gas layer and the upper exposed strata, and the oil layer is inside the casing. The oil layer casing is the deepest among all types of casing, and its mechanical properties and sealing performance are the highest, using steel grades such as J 55, N80, P110, Q125 and V150. The main specifications of oil casing are: 177.8mm(7in), 168.28mm(6-5/8in), 139.7mm(5-1/2in), 127mm(5in), 114.3mm(4-1/2in), etc.Ltd. supplies seamless pipes, structural pipes, fluid pipes, medium, low and high pressure boiler pipes, fertilizer pipes from several major steel mills such as Yegang, […]