新型多重复合切削钻头的研制

Development of New Multiple Compound Cutting Bit

为提高钻头在研磨性硬地层中的机械钻速,延长钻头寿命,研制了新型多重复合切削钻头。该钻头采用"PDC复合片+锥形PDC齿+金刚石孕镶块"3级切削结构,以PDC复合片作为1级切削元件、以锥形PDC齿作为2级切削元件,以金刚石孕镶块作为3级切削元件。多重复合切削钻头具有PDC钻头、牙轮钻头和孕镶金刚石钻头的优点,使钻头既具有较高的机械钻速,又能保持较长的寿命。在青海东坪地区基底花岗岩地层的现场试验中,新型多重复合切削钻头进尺137 m,纯钻时间114.9 h,机械钻速1.19 m/h,比同井段HJ537G牙轮钻头进尺提高128.3%,机械钻速提高40%。多重复合切削钻头为强研磨性硬地层钻井提速提供了一种新型高效的破岩工具。

In order to raise the ROP of bit in the abrasive hard formation and extend bit service life, a new multiple compound cutting bit is developed. The bit adopts the three-level cutting structure of PDC＋cone-shaped PDC tooth＋impregnated diamond segment, with the PDC as the primary cutting component, the cone-shaped PDC tooth as the secondary cutting component and the impregnated diamond segment as the tertiary cutting component. The multiple compound cutting bit takes advantages of the PDC bit, cone bit and diamond-impregnated bit and can maintain the higher ROP and the longer service life. According to test results in the base granite formation of Dongping area of Qinghai Province, the multiple compound cutting bit reached 137 m of bit footage, 114.9 h of pure drilling time and 1.19 m/h of ROP. Compared with the cone bit in the same interval, it increased the footage by 128.3% and raised the ROP by 40%. The multiple compound cutting bit provides a new efficient rock breaking tool for raising drilling speed in highly abrasive and hard formation.