Geological steel pipe

Geological steel pipe is a steel pipe used for core drilling by geological department, it is a kind of long steel pipe for geological drilling with hollow section and no seams around. It consists of drill pipe, drill collar, casing, casing tube well sinker pipe and other parts, in which the basic function of drill pipe is:

(1) raising and lowering the drill bit;

(2) applying drilling pressure; 

(3) transmitting power; 

(4) conveying drilling fluids; 

(5) carrying out special operations: squeezing mud, dealing with downhole accidents and so on.

Drill collar mainly plays the following roles in the drilling process:

(1) to apply drilling pressure to the drill bit; 

(2) to ensure the necessary strength under compression conditions; 

(3) to reduce the vibration, swing, and runout of the drill bit, so that the drill bit works smoothly; 

(4) to control the well slope.

As an important part of the borehole, the casing has the following functions:

(1) prevent the well wall from collapsing, isolate different strata to prevent convection of fluids between strata, and then play a role in controlling the formation fluids and pressures when drilling; (2) assist in the drilling of the borehole control the slant of the borehole.

(2) Assisting surface well control equipment and downhole production equipment to realize their respective functions.