Answer
Kamar yadda igiyar ruwa ke matsawa daga tsayinta kyauta zuwa tsayin aiki, raƙuman ruwa suna karkata, yana haifar da haɓakar diamita na waje ($ O.D.$). Wannan radial fadada $ Delta D$ za a iya kusantar da dabara $\Delta D = 0.02 \ cdot \ frac {(W_f - W_h) \cdot N^2}{D_m}$, inda $W_f$ ne free tsawo da kuma $W_h$ shine aikin tsawo. Idan bazara ta kasance a cikin rami tare da ƙarancin sharewa, zai ɗaure bango, yana haifar da karu mara layi a cikin yanayin bazara da lalacewa na gida. Dole ne masu ƙira su tabbatar da cewa $Bore_{min}> O.D._{max} + \Delta D$. A cikin yanayin zafi mai zafi ta amfani da $17-7PH$ bakin karfe, dole ne kuma a saka ma'aunin haɓakar haɓakar zafin jiki $\alpha$ zuwa lissafin faɗaɗawar radial don hana tsangwama ga bala'i a zafin aiki $T_{op}$.
