Ya zama ruwan dare ga welded carbon karfe bututu su sami iska kumfa a cikin walda, musamman manyan diamita carbon sumul karfe bututu weld pores ba kawai rinjayar da tightness na bututun walda da kuma haifar da zubar da bututun, amma kuma ya zama tushen shigar da lalata, wanda ya haifar da lalata. da gaske yana rage ƙarfi da taurin walda. . Abubuwan da ke haifar da porosity a cikin walda sune: danshi, datti, sikelin oxide da filings na ƙarfe a cikin juzu'i, abubuwan walda da kauri, ingancin saman farantin karfe da kuma kula da farantin gefen karfe, tsarin walda da bututun ƙarfe. kafa tsari, da dai sauransu Flux abun da ke ciki. Lokacin waldi ya ƙunshi adadin da ya dace na CaF2 da SiO2, zai amsa kuma ya sha babban adadin H2, kuma zai haifar da HF tare da babban kwanciyar hankali da rashin narkewa a cikin ƙarfe na ruwa, wanda zai iya hana samuwar pores na hydrogen.

Kumfa galibi suna faruwa ne a tsakiyar ƙullin walda. Babban dalili shine har yanzu hydrogen yana ɓoye a cikin ƙarfen walda a cikin nau'in kumfa. Don haka, matakin kawar da wannan lahani shine a fara cire tsatsa, mai, danshi da danshi daga wayar walda da walda. da sauran abubuwa, wanda ke biye da motsi dole ne a bushe da kyau don cire danshi. Bugu da ƙari, yana da tasiri don haɓaka halin yanzu, rage saurin walda, da rage saurin ƙarfafa ƙarfin narkakken ƙarfe.

Matsakaicin kauri na juzu'in shine gabaɗaya 25-45mm. Matsakaicin girman ɓangarorin juzu'i da ƙaramin ƙima ana ɗaukar su azaman matsakaicin ƙimar, in ba haka ba ana amfani da ƙaramin ƙimar; Ana amfani da matsakaicin halin yanzu da ƙananan saurin walda don tara kauri, kuma ana amfani da mafi ƙarancin ƙimar akasin haka. Lokacin da zafi ya yi yawa, ya kamata a bushe ruwan da aka dawo dashi kafin amfani. Sulfur fatattaka (fashewar sulfur ya haifar). Cracks lalacewa ta hanyar sulfides a cikin sulfur segregation band shiga cikin weld karfe lokacin walda faranti tare da karfi sulfur segregation makada (musamman mai taushi-tafafi karfe). Dalilin haka shine kasancewar hydrogen a cikin baƙin ƙarfe sulfide da karfe tare da ƙarancin narkewa a cikin yanki na sulfur. Don haka, don hana faruwar hakan, yana da kyau a yi amfani da ƙarfe na ƙarfe da aka kashe ko kuma aka kashe tare da ƙananan bandeji mai ɗauke da sulfur.