1) Kewayon diamita mara kyau da diamita shawarar
Mafi girman diamita na sandunan ƙarfe ya fito daga 6 zuwa 50mm, kuma ƙa'idodin da aka ba da shawarar mafi girman diamita na sandunan ƙarfe sune 6, 8, 10, 12, 14, 16, 20, 25, 32, 40, da 50mm.
2) Bambance-bambancen da aka yarda da sifar saman da girman ribbed karfe sandar
Ka'idodin ƙira na ƙananan haƙarƙari na sandunan ƙarfe na ribbed za su cika buƙatu masu zuwa:
Matsakaicin β tsakanin haƙarƙari mai jujjuyawa da axis na sandar ƙarfe bai kamata ya zama ƙasa da digiri 45 ba.Lokacin da kusurwar da aka haɗa ba ta da girma fiye da digiri 70, jagorancin haƙarƙari mai jujjuyawa a bangarorin da ke gaba na sandar karfe ya kamata ya zama akasin haka;
Matsakaicin tazarar ƙaƙƙarfan ƙaƙƙarfan haƙarƙari ba zai zama fiye da sau 0.7 na maƙasudin diamita na sandar ƙarfe ba;
Matsakaicin α tsakanin gefen haƙarƙari mai jujjuyawa da saman sandar ƙarfe ba zai zama ƙasa da digiri 45 ba;
Jimlar gibin (ciki har da nisa na haƙarƙari mai tsayi) tsakanin ƙarshen haƙarƙari masu jujjuyawa a ɓangarorin biyu na madaidaicin sandar ƙarfe ba zai fi 20% na madaidaicin madaidaicin sandar ƙarfe ba;
Lokacin da ƙananan diamita na sandar ƙarfe ba ta wuce 12mm ba, yankin haƙarƙarin dangi bai kamata ya zama ƙasa da 0.055;lokacin da diamita mara kyau shine 14mm da 16mm, yankin haƙarƙarin dangi bai kamata ya zama ƙasa da 0.060 ba;Lokacin da diamita mara kyau ya fi 16mm, yankin haƙarƙarin dangi bai kamata ya zama ƙasa da 0.065 ba.Koma zuwa Karin Bayani na C don lissafin yanki na haƙarƙari.
Sandunan ƙarfe na ribbed yawanci suna da haƙarƙari na tsayi, amma kuma ba tare da haƙarƙari na tsayi ba;
3) Tsawon tsayi da karkatacciyar hanya
A. Tsawon:
Ana ba da sandunan ƙarfe yawanci a cikin tsayayyen tsayi, kuma takamaiman tsayin isarwa ya kamata a nuna a cikin kwangilar;
Ana iya isar da sanduna masu ƙarfafawa a cikin coils, kuma kowane reel yakamata ya zama rebar guda ɗaya, yana barin 5% na adadin reels a cikin kowane tsari (reels biyu idan ƙasa da biyu) ya ƙunshi rebars biyu.An ƙayyade nauyin faifai da diamita na diski ta hanyar shawarwari tsakanin mai siyarwa da mai siye.
B. Tsawon haƙuri:
Bambancin da aka yarda da tsayin sandar karfe lokacin da aka isar da shi zuwa tsayayyen tsayi bazai zama mafi girma ± 25mm;
Lokacin da ake buƙatar mafi ƙarancin tsayi, karkacewar sa shine + 50mm;
Lokacin da matsakaicin tsayin da ake buƙata, karkacewar shine -50mm.
C. curvature da ƙarewa:
Ƙarshen sandar ƙarfe ya kamata a yanke shi tsaye, kuma nakasar gida kada ta shafi amfani.
