Lub nplhaib sab hauv no yog tsim los ntawm high-steel khoom siv, thiab xeb, xws li hauv cov khoom siv hluav taws xob, nkoj, hlau, thiab tshuab hluav taws xob.
Yuav tswj tus txheej txheem zoo thiab thaum twg yuav ua cov txheej txheem tshuaj xyuas? Daim duab qhia no meej rau saib .Cov cov txheej txheem tseem ceeb rau cov khoom siv cylindricrical.
Kaum kaum tus qhauj hauv Suav teb, nruab nrog 1200 tus neeg ua haujlwm, tau txais cov khoom siv los ntawm pab pawg ua tiav, cov khoom siv kho cua sov.
Peb tau nruab nrog cov khoom siv tshuaj xyuas tshiab xws li xim av & Sharple peb-ntsuas ntsuas, ntsuas hluav taws xob, ntsuas qhov ntsuas kom paub tseeb tias qhov kawg tshuaj xyuas thiab ua kom tiav.
Peb yuav muab cov ntaub ntawv hauv qab no tseem yuav tsum muaj cov neeg yuav khoom lag luam ua ntej txhua qhov kev xa khoom rau cov neeg siv khoom los kuaj thiab pom zoo.