Cov txheej txheem tsim cov nplhaib hlau nplaum suav nrog kev npaj khoom, xuas nrig ntaus, hlais, chamfering, electroplating, magnetization, thiab ntim. Txhua kauj ruam yuav siv sij hawm sib txawv, nrog rau tag nrho cov voj voog ntau lawm kwv yees li 10-15 hnub, nyob ntawm qhov zoo ntawm cov hlau nplaum. Lub voj voog tsim rau cov hlau nplaum zoo tib yam yog li 10-12 hnub, rau cov hlau nplaum tsis tu ncua nws yuav siv sijhawm 12-15 hnub, thaum cov hlau nplaum square, uas yuav tsum tau ua ntau yam txheej txheem, lub voj voog ntau lawm kuj yog kwv yees li 10-12 hnub.