Answer
Ƙarfin shear $S_s$ na gawa na ƙarfe gabaɗaya yana da alaƙa da ƙarfin ɗaurensa na ƙarshe $S_u$. Bisa ga Ka'idar Ƙarfafa Makamashi (Von Mises standard), $S_s = 0.577 \cdot S_u$. Don SAE 1070 carbon karfe tare da $ S_u = 210,000$ psi, ka'idar karfi ƙarfi shine $ S_s \ kimanin 121,170$ psi. Lokacin ƙididdige ƙarfin ƙarfin axial $P_r$, muna amfani da $P_r = \ frac {D \ cdot t \ cdot \ pi \ cdot S_s}{K}$. Idan nauyin abin da ake buƙata shine $10,000$ lbs kuma diamita $D $ shine $2.0$ inci, ƙaramin kauri $t$ (a zaton $K=3$) zai zama $t = frac{10000 \cdot 3}{2.0 \cdot \pi \cdot 121170} \kimanin $0. Dole ne injiniyoyi su yi lissafin ƙarfin tsagi, wanda galibi yakan ragu sosai, musamman a cikin allunan aluminium kamar 6061-T6 ($ S_s \ kimanin 27,000$ psi).
