Preheatingtxhais tau hais tias ib tug txheej txheem uas kub weldments nyob rau hauv tag nrho los yog nyob rau hauv weld qhov chaw ua ntej welding. Tshwj xeeb tshaj yog cov khoom zoo rau vuam qib siab zog, hardening nyiam ntawm steel, thermal conductivity, thickness loj weldments, thiab thaum lub ambient kub yog tsawg heev, vuam cheeb tsam feem ntau yuav tsum tau pob tw kom sov ua ntej welding.

Lub hom phiaj ntawm preheating yog txo qhov ceev ntawm qhov txias ntawm cov pob qij txha welded thiab preheating kub. Nws tuaj yeem pom los ntawm lub rooj, kev ua kom sov tuaj yeem txo qhov txias txias, tab sis tsis cuam tshuam rau lub sijhawm kom nyob hauv qhov kub thiab txias, uas yog qhov xav tau heev. Yog li thaum welding steel nrog ib tug hardening nyiam, kom txo tau qhov txias txias txo lub hardening nyiam ntawm lub ntsiab txheej txheem ntsuas, yog kom sov li, es tsis txhob nce lub zog tawm tswv yim.