Application

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  Casing

  The pipe inserted into the drilling hole from the surface as the lining of the well wall, and the main material between the pipes is J55 N80 P110 steel grade, and the hydrogen sulfide corrosion resistant C90 T95 steel grade, and the lower steel grade (J55 N80) can be welded steel pipe.
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  Tubing

  A pipe inserted from the surface into the casing to the oil layer through the coupling or integral connection between the pipes to the pumping unit to transport the oil layer through the tubing to the surface. The main material is J55 N80 P110.

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  The structure of the tubing coupling is

  The tubing end and the inner wall of the coupling are connected by conical thread, and the tubing end of the coupling body is connected by flat thread with the same thread and pitch, which has the characteristics of relieving the stress concentration at the root of the external thread of the tubing connected by a single cone thread, and is not easy to produce fatigue and fracture, and the connection effect is good and effectively prevents the accident of the oil well string breaking.