23-1.Axis thickness calculation formula

23-1. Axis thickness calculation formula Symbol description and unit
(1) Shaft subject to bending Maru-jiku Round shaft:
d=(32*M/(ƒÎ*ƒÐa))1/3 kmml
d=

Hollow shaft:
d2=(32*M/(ƒÎ*ƒÐa*(1-k4))1/3 kmml
d2=
k: Ratio of inner diameter to outer diameter of the shaft
(k=d1/d2)
d1F Inner diameter of hollow shaftkmml
d2F Outer diameter of hollow shaftkmml

MF Maximum bending moment acting on the shaft kkgf¥mml
ƒÐaF Allowable bending stress of the shaft kkgf/mm2l
(2) Shaft receiving twist Round shaft:
d=(16*T/(ƒÎ*ƒÑa))1/3 kmml
d=

Hollow shaft:
d2=(16*T/(ƒÎ*ƒÑa*(1-k4))1/3 kmml
d2=
k: Ratio of inner diameter to outer diameter of the shaft
(k=d1/d2)
d1FInner diameter of hollow shaftkmml
d2F Outer diameter of hollow shaftkmml

TFMaximum torsional moment acting on the shaft kkgf¥mml
ƒÑaF Allowable torsional stress of the shaft kkgf/mm2l
References: "Machine Official Collection" (co-authored by Masaaki Oishi / Tatsuo Inami) Mechanical Design Shaft Thickness Page 86 Refer to the shaft that receives bending and the shaft that receives twisting.