Required stress area screw

Eqn. 1

Stress area

A_S

609

mm²

Bolts total force	F_SG	=	100	kN
Clamping length	l_k	=	50	mm
Yield strength	R_{p 0,2}	=	640	MPa

100

Calc 1

Stress area screw connection80

The total bolts force F_SG is determined from the operating force and the required clamping force.

The clamping length l_k denotes the total thickness of the parts connected under pressure. To optimize a screw connection, the clamping length should be three to five times the screw diameter.

The following simplified assumptions apply8084

only applicable for shaft screws and not for expansion screws
Friction coefficient μ_G = 0.12 in the thread
Tightening factor k_A = 2.5 for tightening with a torque wrench

The clamp connection is successful if the selected stress area A_S of all bolts is larger than calculated.

Yield strength R_{p 0.2}

Strength class 8.8 640 MPa

Strength class 10.9 900 MPa

Strength class 12.9 1080 MPa

Muhs, D, et al. / Roloff Matek Maschinenelemente / Vieweg / Wiesbaden / 2005 / 17. Auflage

Muhs, D, et al. / Roloff Matek Maschinenelemente, Tabellen / Vieweg / Wiesbaden / 2005 / 17. Auflage

Required stress area screw

Yield strength Rp 0.2

Yield strength R_{p 0.2}