井底牙轮钻头的钻速方程及现场应用

以岩石侵入理论为基础,在考虑井底压力的条件下,建立牙轮钻头的钻速模型。结果表明:在地层由软、中硬到硬地层过渡过程中,钻速方程能够解释不同破岩方式下牙轮钻头的机械钻速问题;随着刃尖角的增大,锥形齿和楔形齿的牙齿侵深都呈指数递减趋势;随着井眼内钻井液柱压力的增大,侵入深度呈指数递减趋势,其中锥形齿递减趋势大于楔形齿;模型理论钻速计算结果与实际钻速数据接近,最小欧式距离为25.8。

Drilling rate model of cone bit in bottom hole and field application

Based on rock intrusive theory and considering the bottom hole pressure, the problems of rock breading of cone bit were studied, a drilling rate model in actual drilling was built. The results show that in the process of transition from soft, medium-hard to hard formation, drilling rate model can explain the problems of penetration rate of cone bit in different rock breaking ways. The invasion depths of conical insert and chisel teeth decrease exponentially with bit angle and fluid column pressure increasing, and conical insert is more obvious than chisel teeth. The calculation results of drilling speed of model are close to the data of drilling speed in field. The minimum euclidean distance is 25.8.