大口径钻井钻压设计探讨

Probing into the Bit-Pressure Design for Large-Diameter Shaft Drilling

重点探讨了大口径钻井过程中钻压设计的四项基本原则,并就不同岩层钻进条件下的钻压设计提出了一些看法,认为钻压是提高钻进速度、保证钻井效率的关键参数之一;在设计钻井工艺时,必须严格按照岩层的力学特性参数来设计钻压,在实际钻进过程中,钻压应根据岩层的变化不断调整,以达到最佳钻进效果;在地层交界处或地层破碎带钻进时,必须及时修正钻压值;井斜是钻压调整的重要依据;从有效破岩和钻头刀具使用寿命的角度考虑,钻压设计不得超过最大钻压值。

This paper focuses on discussion of four basic principles of drilling pressure design for the large-diameter well drilling and presents some opinions about the bit weight design in drilling in different rock stratums. The bit weight is one of the key parameters to increase drilling speed and ensure drilling efficiency. For achieving optimum drilling effects, the bit weight must be designed and continuously adjusted in drilling operation according to the mechanical idiosyncrasy parameters and the terrane changes. When drilling at the terrane juncture and fracture zone, the bit pressure value should be regulated timely. The well-boring inclination is the important basis for adjusting the bit weight. Considering rock breaking effectively and the longer service life of the bit tool, the bit weight should not exceed maximum value. This paper provides a certain reference for the bit weight design of largediameter well drilling technology.