“NNAL”类长圆柱轴承保持架加工浅析

Analysis on the cage process of long cylindrical roller bearing"NNAL

“NNAL”类轴承是石油钻机轴承的老产品.该类产品的组件保持架自试制以来,有十多年的生产历史.但生产,中冲孔、围圈的废品率高达30%以上.通过对原加工工艺过程分析,跟踪验证得知原加工工艺工序繁多,执行工艺难度大,加工质量难以保证;尤其是先冲孔后围圆,质量更是难以保证.同时,围圆时为了保证对焊后窗孔不错位,焊接窗孔与其他窗孔尺寸相差0.1mm,这给切端头、焊接带来很大困难,造成此工序废品率较高.经过研究、分析认为原加工工艺执行难度大,应重新设计加工工艺.改进后的加工工艺比原工艺少3～4道工序,并改变了工序的顺序,先围圆后冲孔,避免了因焊接窗孔而造成的废品.使产品合格率稳定在98%以上.经过生产验证,改进合理,保证产品满足设计要求,大大提高了产品质量.

The'NNAL'type bearing is a kind of bearing for o il well rig,and it is an old product in bearing industry.It has a history of more than ten years since t he cage component of this kind of bearing was manufactured on trial.But in manufacture,the scraps rate of punching and rounding amount to more than 30%.Through a nalyzing and validating the old tech nological process,it is found that the procedures of the old process are too complic ated.It is hard to perform the process and to ensure the quality.Especially punching is before rounding,so it is more diffic ult to ensure the quality.To avoid th e misplacement of the cage pocket of window type when weldi ng,the dimension of the welded window is a little different with that of other windows (about 1mm).It brings difficulties to cut end an d weld,and it causes more scraps in th is procedure.After studying and ana-lyzing,the technological process s hould be re-designed.The re-design ed process has removed 3or 4procedur es,and the se-quence of procedures is changed,such as putting rounding before punchin g.This sequence can avoid the scraps when welding.The new process ensures that the quality rate of products amounts to more t han 98%.Through validating the new p rocess in manufacture,the product quality is improved remarkably and the products also meet the needs of product desig ning.