Study And Software Development Of Single Screw Drill Assembly Optimization Selection

This paper studies on the optimization selection method of single screw drilling tools,and this actual demand was carried out by the drilling sit.This paper starts the research based on the two aspects: the drilling engineering and single screw drilling tools,and combining the research results I completed the software development of single screw drilling assembly type selection.Torques are proportional to presssure drops in screw drilling tool. Although the rotating speed will change with pressure drop, speed change is very small in a certain range. Pressure drop can be read from the pump pressure gage,so we can drill according to the pump pressure gage. The drill string friction resistance is very large in the directional and horizontal well,so it’s diffcult to read the weight from the weight indicator.So drilling according to the pressure gage shows great superiority. Torque on bit can be figured out according to the pressure drop on the pump pressure gage. This is the prominent advantage of application of screw drilling tools in the directional drilling. Based on the prominent performance of screw drill tools in drilling field, we choose to study the optimization selection of the screw drill tool assembly.Screw drill tool assembly’s selection involving following aspects: Bit planning, casing string design, tubing string design, drill string design and choice of drilling rig etc. Bit planning, casing string design and drill string design had been systematically analyzed in order to get the method of optimization selection of the screw drill tool assembly. The static characteristics of the drill string had been analyzed by ANSYS simulation, supplemented the deficiency of the theoretical analysis.This paper summarized a scientific method of optimization selection of single screw drill assembly in the drilling engineering through analyzing the drilling engineering system and screw drill tool performance research,and finished the software develpment of single screw drill assembly optimization selection.It provides a better choice for engineering site to choose single screw drill assembly.