This increase can be achieved by the application of the drilling at a constant penetration rate based on the footing per cycle.

The paper develops general interpolation principals for parametric curves with constant feedrate, and contour error's approximate evaluations are discussed also.

Based on analysis of interpolation mechanism for parametric curve, in this paper, 2D and 3D spiral curves interpolation algorithms with constant feedrate are developed on the one hand and the contour errors and corresponding approximate calculation formulations are discussed on the other.

High ROP drilling fluid is formulated by adding fast drilling additives into the mud without altering the original rheology, solids content and the dispersibility of the mud, thus greatly improves the lubricity of the mud and reduces the torque of the drill pipes.

Based on the project example,the problems affecting portable drill′s drilling speed are statistically analyzed,then examine the effect after improvement.

The main factors affected on the drilling speed of drilling method are rock-cutting and mud discharge.

By researching on the characteristics of quaternary Q_1 strata,some relationships between bucket teeth angle and drilling speed have been discovered,and the bucket teeth angle formula under optimal drilling speed has been fitted out by least square method.