The wear rate of a diamond bit determines its service l […]
The wear rate of a diamond bit determines its service life. With a grooved drill pipe with a certain footage efficiency, the service life ultimately determines the level of drilling costs. Whether it is a manufacturer of drill bits or a geological drilling operator, understand The influencing factors of drill bit wear rate can save drilling cost to the greatest extent, including four major factors: weight on bit, rotation speed, tooth wear state and temperature.
1. The impact of weight-on-bit on tooth wear speed: where: D1 and D2—the weight-on-bit influence coefficient is related to the size of the roller cone bit. When weight on bit = diamond bit D2/D1, the wear rate of the teeth is infinite, that is, D2/D1 is the limit weight on bit of the drill bit.
2. The effect of rotation speed on tooth wear speed: when the WOB is constant, the rotation speed increases, and the tooth wear speed also increases. The effect of rotation speed on tooth wear speed, where: Q1 and Q2-coefficients determined by the type of drill.
3. The influence of tooth wear status on tooth wear speed: where: C1—tooth wear slows down the PDC bit coefficient; Af—formation abrasiveness coefficient. The area of the wedge-shaped teeth will increase with the wear of the tooth height, and the wear rate will also decrease with the wear of the tooth height.
4. The influence of temperature on the speed of tooth wear: Under the critical regulation, the temperature of the drill bit matrix rises sharply, the power consumption increases sharply, and the drill even burns. When P×n reaches the critical value, the temperature of the carcass rises sharply from 100~200°C to 600~700°C. For specific rocks, the critical value of P×n is basically constant.