Qhov tseem ceeb tshaj plaws ntawm lub tshuab pwm yog lub hau npog. Cov pwm no yog qhov txias tshaj plaws ntawm kev tuag. Lub "mould car" nyob rau hauv lub ntsiab lus dav yog lub npe ntawm pwm rau txhua qhov hauv lub tsheb.Piv txwv li, stamping tuag, txhaj mould, forging tuag, casting wax cwm , iav pwm thiab lwm yam.
Lub voj voog feem ntawm lub cev tsheb feem ntau muab faib rau qhov chaw npog, qhov chaw nqaj qhov tob thiab qhov chaw ntawm lub thwj cim. Qhov seem ntawm cov thwj cim uas qhia tau meej txog cov yam ntxwv ntawm daim duab tsheb yog daim npog lub tsheb. Yog li ntawd, lub pwm ntau lub tsheb tuaj yeem hais tias "auto cover parts stamping die" .Cov tsheb npog cov tuag rau luv.Piv txwv li, vaj huam sib luag trim tuag, pem hauv ntej rooj phaj punching tuag, etc.