Official Answer
Answer
Yin amfani da madaidaicin faɗaɗa wanda ya wuce girman zoben karkace ya wuce iyakarsa na roba zai haifar da nakasu na dindindin, wanda aka sani da 'saita'. Zoben ba zai dawo zuwa diamita na asali ba, wanda zai haifar da asarar 'manne' a kan tsagi. A ilimin lissafi, matsakaicin faɗaɗa $E_{max}$ kafin bayarwa ana sarrafa shi ta hanyar dabara $\sigma = \frac{E \cdot t \cdot \Delta D}{D_m^2} <S_y$. Idan zoben bai kama gindin tsagi ba, zai iya girgiza ko juyawa yayin aiki, wanda zai haifar da lalacewa (fretting) da gazawar ƙarshe. Don rage wannan, yakamata a ƙera mandrels tare da tasha mai wuya ko girman daidai da diamita na shaft tare da mafi ƙarancin izinin da ake buƙata don shigarwa.
