1. Kumfa
Kumfa galibi suna faruwa ne a tsakiyar ƙullin walda, kuma hydrogen har yanzu yana ɓoye a cikin ƙarfen walda a cikin nau'in kumfa. Babban dalili shi ne cewa wayar walda da ruwa suna da danshi a saman kuma ana amfani da su kai tsaye ba tare da bushewa ba. Har ila yau, halin yanzu yana da inganci a lokacin aikin walda. Ƙananan, saurin waldawa yana da sauri, kuma wannan kuma zai faru idan an ƙara ƙarfafa ƙarfin ƙarfe.

2. Yankewa
Ƙarƙashin ƙaƙƙarfan tsagi ne mai siffar V wanda ke bayyana a gefen walda tare da tsakiyar layin walda. Babban dalili shi ne cewa saurin walda, halin yanzu, ƙarfin lantarki, da sauran yanayi ba su dace ba. Daga cikin su, saurin walda ya yi yawa kuma na yanzu bai dace ba. Yana da sauƙi don haifar da lahani mara kyau.

3. Thermal fasa
Dalilin fashewar zafi shine lokacin da damuwa na walda ya yi yawa, ko kuma lokacin da silica na SIlicone a cikin karfen weld ya yi girma sosai, akwai wani nau'i na sulfur mai fashewa, blank shine farantin karfe mai karfi mai ban sha'awa na sulfur (na nasa ne). Karfe mai laushi), tsagewar da sulfides ke haifar da shiga cikin ƙarfen walda yayin aikin walda.

4. Rashin isashen walda
Ƙarfe na walda na ciki da na waje bai isa ba, kuma wani lokacin walda ba ya shiga.
Hanyar ƙididdigewa don bututun ƙarfe na welded: (diamita na waje - kauri na bango) * kauri bango * 0.02466 = nauyi a kowace mita na bututun ƙarfe na welded {kg
Galvanized karfe bututu lissafin: ( waje diamita - bango kauri) * bango kauri * 0.02466 * 1.06 = nauyin welded karfe bututu da mita {kg