Lub voj voog txij nkawm rau cov saw hniav nyob ntawm kev siv zaus, cov khoom raug txiav, thiab qhov chaw ua haujlwm. Kev tshuaj xyuas yooj yim tom qab txhua qhov kev siv yog cov txheej txheem tu yooj yim tshaj plaws. Tsom ntsoov rau kev tshuaj xyuas cov hniav kom chipping, tawg, los yog hnav tseem ceeb, thiab ntxuav tej ntoo chips, hlau shavings, los yog residue residue adhering rau cov hniav. Cov kauj ruam no yog qhov tseem ceeb tshwj xeeb tshaj yog rau cov hlau ua haujlwm saws, vim tias cov khib nyiab seem tuaj yeem ua rau hnav thiab xeb.
Yog tias siv ntau zaus (piv txwv li, kev ua haujlwm tas li txhua hnub), kev saib xyuas ntau dua yog pom zoo txhua lub lim tiam, suav nrog kev ntxuav, siv cov xeb- tiv thaiv roj, thiab tshuaj xyuas qhov nro thiab ncaj. Rau lub tshuab pom cov hniav xws li band saws, nws tseem yuav tsum tau kuaj xyuas cov kab nrib pleb los yog cov cim qhia tsis zoo, thiab hloov tam sim yog tias tsim nyog kom tsis txhob tawg.
Rau lub sijhawm ntev - khaws cia, txawm tias tsis siv, nws raug nquahu kom kuaj xyuas thiab khaws cov saw txhua 1-3 lub hlis, tsom rau kev tiv thaiv xeb thiab kho cov xwm txheej khaws cia. Cov hniav pom muaj ntau dua rau oxidation, tshwj xeeb tshaj yog nyob rau hauv ib puag ncig ntub, yog li tsis tu ncua re- roj lossis hloov cov ntim tshuaj tiv thaiv xeb yog tsim nyog.