Thaum siv cov tshuab dhos tsis siv neeg, qhov chaw txheeb ze ntawm lub cuab yeej thiab cov khoom ua haujlwm yuav tsum tau hloov kho raws li daim npav tshuab cuab yeej hloov kho, thiab kev sib tw tig yuav tsum tau ua tom qab kev hloov kho, thiab thawj daim ntawv tsim nyog tuaj yeem ua tiav;Ua tib zoo saib xyuas cov cuab yeej hnav thiab workpiece loj thiab nto roughness thaum lub sij hawm machining.