Crack Defect

Cracking yog ib qho kev sib txuas ntawm cov kav hlau threaded thiab muaj kev cuam tshuam loj rau kev nyab xeeb ntawm cov kav dej. Nws tsis tsuas yog ua kom nrawm nrawm ntawm cov kav hlau steel tab sis tseem ua rau muaj kev pheej hmoo ntawm kev tawg tawg, yog li tsim kev nyab xeeb ntau heev. Cov xwm txheej ua rau cov yeeb nkab steel sib txawv thiab tuaj yeem muab faib ua cov tawg kub thiab txias tawg. Kub tawg tshwm sim thaum lub sij hawm vuam txheej txheem thaum tej yam khoom sib sau thiab nws thiaj li tawg vim weld seam contraction, feem ntau tsim transverse kab nrib pleb nyob rau hauv cov kev taw qhia ntawm tawg propagation. Cov kab nrib pleb txias, ntawm qhov tod tes, tshwm sim thaum lub caij txias tom qab vuam, thaum cov khoom hloov pauv ntawm martensitic kub. Cov kab nrib pleb txias feem ntau cuam tshuam los ntawm cov yam ntxwv xws li kev ntxhov siab, microstructure hardened, thiab diffusible hydrogen, uas tuaj yeem ua rau kev tsim ntawm ob qho tib si transverse thiab longitudinal tawg.