摘要
钻头泥包的本质是泥质岩屑的粘附。为研究各因素对PDC钻头材料表面泥质岩屑粘附性能的影响规律,基于直剪切试验方法,将粘附力作为粘附性能评价指标,进行了泥质岩屑粘附性能试验研究。试验结果表明,在其他条件不变的情况下,粘附力随泥质岩屑含水体积分数的变化呈抛物线规律,在含水体积分数为30%左右时粘附力达到最大值;与以高岭石为主要粘土矿物的泥质岩屑相比,以蒙脱石为主要粘土矿物的泥质岩屑的粘附性更强;泥质岩屑的粘附力与颗粒尺寸成反比;与合金钢相比,泥质岩屑在铸造碳化钨表面的粘附力是在其表面的1.5倍;水作为粘附介质时,粘附力最大,油作为粘附介质时,粘附力最小,在水中添加体积分数为6%的KCl后,粘附力变小,但仍大于油作为粘附介质时的粘附力。
The adherence of shale cuttings to bit surfaces is the essence of bit balling. In order to study the effects of factors on the adherence, an experiment is carried out by using direct shear test method and taking adhe- sive force as adherence evaluation index. The experimental results show that, the adhesive force follows the parabol- ic trend along with the change of water content of shale cuttings, and it can reach the maximum value when the wa- ter content is about 30% ; compared with shale cuttings with clay minerals mainly composed of kaolinite, those with clay minerals mainly composed of montmorillonite have the higher adherence ; the adhesive capacity is inverse- ly proportional to the particle size; the adhesive force on the cast tungsten carbide surface is 1.5 times that on the alloy steel surface; the adhesive force will be maximum when water is the adhesion medium and minimum value when oil is the adhesion medium; the adhesive force will be reduced when 6% KC1 is added into the water, but it is still greater than that of the oil taken as the adhesion medium.
出处
《石油机械》
2015年第2期5-8,共4页
China Petroleum Machinery
基金
国家"十二五"科技重大专项"胜利油田薄互层低渗透油田开发示范工程"之"薄互层水平井导向PDC钻头优化设计及导向特性研究"(05Z12020300)
