Round blades feem ntau yog ua los ntawm cov hlau tshwj xeeb zoo. Niaj hnub no, round hniav yog siv nyob rau hauv ntau yam lag luam thiab yog heev ntau. Koj yuav tsum paub tias ntxiv rau cov khoom siv hlau xaiv, kev kho cua sov yog ib qho tseem ceeb tshaj plaws txawm tias cov hniav puag ncig yog yooj yim siv. Yuav kom nkag siab txog kev siv cov hniav zoo nkauj, koj yuav tsum xub nkag siab txog cov txheej txheem kev kho cua sov ntawm cov hniav.
Tom qab lub round hniav yog forged thiab roughed los ntawm lub tshuab dhos, nws yuav tsum tau kho cua sov. Feem ntau siv cov kev kho cua sov rau cov hniav puag ncig yog ntsev da dej kub kho thiab kho cua sov lub tshuab nqus tsev. Txawm siv txoj kev kho cua sov twg los xij, yuav tsum xaiv cov khoom sib txawv. Piv txwv li, qee cov ntaub ntawv tuaj yeem tso lawv qhov nyuaj tshaj plaws thaum lawv cov qauv nce mus txog 800 degrees, thiab qee qhov tuaj yeem tso lawv qhov nyuaj tshaj plaws thaum lawv ncav cuag 1100 degrees.
Thaum xaiv cov khoom siv puag ncig cov hniav mus txog qhov nyuaj tshaj plaws thaum kho cua sov, nws yuav tsum tau tempered. Txawm hais tias cov ntaub ntawv ntawm cov hniav yog dab tsi, nws yuav tsum tau tempered tsawg kawg yog 2-3 zaug ua ntej cov hniav tuaj yeem xa cov kev ua tau zoo. Yog tias tus naj npawb ntawm temperings tsawg dua, nws yuav yog Qhov no ua rau cov ntaub so ntswg hauv cov hniav tsis sib xws thiab ua rau cov hniav siv tau yooj yim. Tom qab ob los yog peb zaug ntawm tempering, cov hniav puag ncig yog muab tso rau hauv chav tsev kub cua kom txias, thiaj li hais tias kev kho cua sov ntawm round hniav tiav.
Nco ntsoov, txawm hais tias nws yog cov hniav puag ncig lossis lwm cov hniav, lub hardness thaum siv yog tau los ntawm tempering. Feem ntau, qhov siab tshaj plaws hardness yog tau los ntawm quenching thiab cua sov, thiab ces tempered kom tau qhov xav tau hardness ntawm round hniav.