耐高温电镀镍锰合金胎体金刚石钻头的钻进性能研究

Study on drilling performance of heat-resisting electroplated diamond bit with Ni-Mn alloy matrix

摘要:

深部钻探的复杂钻进条件对孕镶金刚石钻头的性能提出了更高的要求。为了提高电镀金刚石钻头的使用范围，研究了MnCl₂和丁炔二醇乙氧基化合物（BEO）对镍基镀层表面形貌、显微硬度和热稳定性的影响，对比研究了300 ℃退火1 h后纯Ni金刚石钻头、Ni-Mn金刚石钻头和添加BEO的Ni-Mn金刚石钻头的钻进性能。结果表明，300 ℃退火1 h后的纯Ni镀层显微硬度下降到300 HV。以此镀层为胎体的金刚石钻头由于胎体耐磨性过低，导致金刚石过早脱落，钻头寿命只有2.94 m。Ni-Mn镀层和添加BEO的Ni-Mn镀层都具有良好的热稳定性，300 ℃退火1 h后硬度分别提高到640 HV和693 HV。Ni-Mn胎体电镀金刚石钻头在退火后兼有合适的钻进寿命和钻进效率，钻头寿命可以达到4.67 m。而添加BEO的Ni-Mn胎体金刚石钻头在本文试验中由于胎体硬度过高，导致金刚石无法正常出刃而失效。

Abstract:

The complex drilling conditions of deep drilling put forward higher requirements for the performance of impregnated diamond bits. To improve the application range of electroplated diamond bits， the effects of MnCl₂ and butynediol ethoxylate （BEO） on the surface morphology， microhardness， and thermal stability of the nickel base coating were studied. The drilling performance of pure Ni matrix diamond bit， Ni-Mn matrix diamond bit， and Ni-Mn matrix diamond bit with BEO as an additive after annealing at 300℃ for 1 hr was compared. The results show that the microhardness of pure Ni decreases significantly to 300HV after annealing at 300 ℃ for 1 hr， and the wear resistance of the annealed diamond bit with this matrix is too low， which leads to premature diamond shedding and a short service life to 2.94m. Both Ni-Mn coating and Ni-Mn coating with BEO added have good thermal stability， and the hardness increases to 640HV and 693HV respectively after annealing at 300℃ for 1hr. Ni-Mn matrix diamond bit has both suitable drilling life and drilling efficiency after annealing， and the bit life can reach 4.67m. However， the annealed Ni-Mn matrix diamond bit with BEO as an additive fails due to the matrix’s high microhardness.