适合于研磨性硬地层的新型孕镶金刚石钻头优化设计试验研究

Experimental Research on Optimization Design of a New Type of Impregnated Diamond Bit Suitable for Abrasive Formation

针对现有钻头在研磨性硬地层中普遍存在钻速低、寿命短的问题,研制了一种孕镶钻齿,通过室内试验优选胎体配方和金刚石参数,设计了一种新型孕镶金刚石钻头,并进行了现场应用。孕镶钻齿设计为圆柱形,以铸造碳化钨和碳化钨为胎体骨架材料,以浓度为25%、粒度为80目的天然金刚石颗粒为磨削元件,采用热压工艺烧结合成。新型孕镶金刚石钻头冠部形状设计为直线-圆弧-圆弧型双锥剖面,采用等间距高密度径向布齿,布齿间距为2 mm,采用横卧和竖立两种方式周向布齿。现场应用结果表明,新型孕镶金刚石钻头可提速79%左右,使用寿命是牙轮钻头寿命的2倍以上。

According to the problems of low drill speed and short life of the bits in abrasive formation, a type of impregnated drill tooth is developed. The matrix formula and diamond parameters are optimized through laboratory test, and then a new type of impregnated diamond bit is designed and applied. The impregnated drill tooth is de- signed for cylindrical, the matrix skeleton materials are cast tungsten carbide and tungsten carbide, and the grind- ing elements are natural diamond particles with concentration of 25% and grain size of 80 mesh. The crown shape of impregnated diamond bit is linear-arc-arc double cone profile, the radial tooth arrangement is equal-interval and high-density, the distance between drill teeth is 2 mm; the circumferential tooth arrangement is in two modes of standing and lying. Field application results show that the drill speed of the new type of impregnated diamond bit can be improved by about 79%, the bit life is two times of the average life of the cone bits in this area.