The abrasion mechanism and cause analysis for straight well rod string;

The dynamics simulation of rotating rod string in well bore;

A three-dimensional dynamic simulation model of rod string in actual borehole was established based on the characteristics of actual well track and system dynamics theory.

Prediction of serious abrasion position and mechanism of uneven abrasion between sucker rod string and tubing;

Velocity distribution model of annular flow and computing model of liquid friction of the sucker rod string were established according to constitutive equation and momentum conservation equation of the power law fluid of polymer flooding rod pumping systems.

According to working characteristics of a surface driving screw pump system,torsion load and axial force of sucker rod string which is analyzed and calculated in this article.

The current status of screw pump, development tendency and producing principle ofscrew pump are summarily introduced in the thesis, and then according to features ofsurface-drived screw pump, the force of sucker rod string, .

With regard to the well deflection and the stress of sucker rod under the well,the existing problems on the design of sucker rod in deviating holes were pointed out,and a rod mechanical model was constructed to design the sucker rod and the space of installing stabilizer.

This paper discussed some problem encountered in calculation of gas column natural frequency based on the frequency response function method.