Cov ntaub ntawv txiav: Kev txiav hlau qhuav txias yog qhov tsim nyog rau kev ua cov hlau tsis tshua muaj hlau, hlau nruab nrab thiab qis carbon, hlau cam khwb cia, hlau qauv thiab lwm yam hlau uas muaj qhov nyuaj hauv qab HRC40, tshwj xeeb tshaj yog cov hlau modulated.
Piv txwv li, hlau puag ncig, hlau kaum sab xis, hlau kaum sab xis, hlau channel, raj plaub fab, I-beam, txhuas, yeeb nkab hlau tsis xeb (thaum txiav yeeb nkab hlau tsis xeb, daim ntawv hlau tsis xeb tshwj xeeb yuav tsum tau hloov)