18. Cov kauj ruam twg yog cov kauj ruam tseem ceeb tshaj plaws hauv cov txheej txheem ntau lawm los ntawm high- zaus welded ncig cov hlab? Vim li cas?

Cov txheej txheem tseem ceeb tshaj plaws nyob rau hauv cov txheej txheem ntau lawm ntawm high {{0 zaus} zaus welded puag ncig yog siab- zaus vuam.
Muaj peb qho laj thawj, ua ntej, lub vuam zoo ncaj qha cuam tshuam rau cov khoom lag luam siab thiab nruj ntawm cov yeeb nkab {{zaus cuam tshuam rau kev ua tau zoo tag nrho thiab kev pabcuam lub neej ntawm cov khoom.
Qhov thib ob, cov txheej txheem vuam yog qhov nyuaj thiab nyuaj rau kev tswj hwm: high {}} kev tswj hwm weld, thiab kev saib xyuas ntawm kev txawj ntse thiab kev paub dhau los.
Ib qho ntxiv, cov nqi vuam yog tus nqi siab: high {{0} Cov nqi vuam siv tau kim, thiab cov nqi zog hauv vuam tseem muaj siab. Yog li ntawd, txhim kho vuam ua haujlwm thiab zoo yog qhov tseem ceeb tshaj plaws kom txo cov nqi ntau lawm.