Yadda za a zaɓi na ƙirƙira rabo?

Yayin da rabon ƙirƙira ya ƙaru, ana matse ramukan ciki kuma an karye simintin simintin gyare-gyaren dendrites, wanda ke haifar da gagarumin ci gaba a cikin ingantattun kaddarorin injuna na ƙirƙira. Amma a lokacin da elongation ƙirƙira rabo rabo ya fi 3-4, kamar yadda ƙirƙira rabo rabo ya karu, bayyanannun fiber Tsarin an kafa, haifar da kaifi rage a cikin plasticity index na transverse inji Properties, haifar da anisotropy na ƙirƙira. Idan rabon sashin ƙirƙira ya yi ƙanƙanta sosai, ƙirƙira ba zai iya cika buƙatun aikin ba. Idan ya yi girma sosai, yana ƙara aikin ƙirƙira kuma yana haifar da anisotropy. Don haka, zabar rabon ƙirƙira mai ma'ana abu ne mai mahimmanci, kuma ya kamata a yi la'akari da batun rashin daidaituwa a lokacin ƙirƙira.

Yawan ƙirƙira rabo yawanci ana auna ta matakin nakasawa yayin elongation. Yana nufin ma'auni na tsayi zuwa diamita na kayan da za a kafa, ko rabon yanki na giciye na albarkatun ƙasa (ko prefabricated billet) kafin ƙirƙira zuwa yanki na yanki na samfurin da aka gama bayan ƙirƙira. Girman rabon ƙirƙira yana shafar ƙayyadaddun kayan aikin ƙarfe da ingancin ƙirƙira. Ƙara ƙirƙira rabo yana da fa'ida don haɓaka microstructure da kaddarorin karafa, amma ƙimar ƙirƙira mai ƙima kuma ba ta da fa'ida.

Ka'idar zaɓin rabon ƙirƙira shine zaɓi ƙarami gwargwadon yuwuwar yayin tabbatar da buƙatu daban-daban don ƙirƙira. Ana ƙididdige ƙimar ƙirƙira gabaɗaya bisa ga sharuɗɗa masu zuwa:

1. Lokacin da high quality-carbon tsarin karfe da gami tsarin karfe suna da yardar kaina ƙirƙira a kan guduma: for shaft irin forgings, su kai tsaye ƙirƙira daga karfe ingots, da ƙirƙira rabo da aka lasafta dangane da babban sashe ya zama ≥ 3; Matsakaicin ƙirƙira da aka lissafta dangane da flanges ko wasu sassa masu tasowa yakamata su zama ≥ 1.75; Lokacin amfani da billet ɗin ƙarfe ko kayan birgima, ƙimar ƙirƙira da aka ƙididdige akan babban sashin shine ≥ 1.5; Matsakaicin ƙirƙira da aka ƙididdige kan flanges ko wasu sassan da ke fitowa ya zama ≥ 1.3. Don ƙirƙira zobe, rabon ƙirƙira ya kamata gabaɗaya ya zama ≥ 3. Don ƙirƙira diski, an ƙirƙira su kai tsaye daga ingots na ƙarfe, tare da ƙimar ƙirƙira ta ≥ 3; A wasu lokuta, haɓaka ƙirƙira ya kamata gabaɗaya ya zama> 3, amma tsari na ƙarshe yakamata ya zama>.

2. High gami karfe billet masana'anta ba kawai bukatar kawar da tsarin lahani, amma kuma bukatar samun wani karin uniform rarraba carbides, don haka ya fi girma ƙirƙira rabo dole ne a soma. Za'a iya zaɓar rabon ƙirƙira na bakin karfe a matsayin 4-6, yayin da ƙirƙira rabo na ƙarfe mai sauri yana buƙatar zama 5-12.