1. Qhov roughness ntawm qhov chaw yog tsawg dua li tig, milling thiab sib tsoo.
2. Lub zog thiab qhov nyuaj ntawm cov xov dov tuaj yeem txhim kho tau vim yog kev ua haujlwm txias.
3. Tus nqi siv cov ntaub ntawv siab, qhov tsim tau ntau dua li ntawm kev txiav, thiab nws yooj yim kom paub txog kev ua haujlwm tsis siv neeg.
4. Lub neej ntawm lub pwm dov ntev heev. Tab sis cov xov dov yuav tsum tau kom qhov nyuaj ntawm cov khoom siv ua haujlwm tsis pub tshaj HRC40.
5. Yuav tsum muaj qhov tseeb ntawm qhov loj me.
6. qhov kev txiav txim siab thiab qhov nyuaj ntawm lub dov tuag kuj siab, yog li nws nyuaj rau tsim cov tuag.
7. Nws tsis haum rau dov cov xov nrog cov hniav asymmetric.