增大滚子直径法对KX 84-250牙轮钻头滚动轴承改型的理论研究

he rock bit is the major tool of petroleum drilling, its service life directly depends on the life-span of bearing system. In this paper the influence on the life-span of cylindrical roller bearing of the KX 84-250 rock bit of increasing the diameter of the roller is analyzed, and based on this the contrast calculation of before and after retrofit is done. The result of calculation indicates, increase and diameter of the roller, the bearing life-span can really be improved. But,if the roller azimuth and number of the rollers keeps constant, increasing the roller diameter simply can improve the Operational capability very limited.