ON THE EFFECTS OF CIRCULAR BOLT PATTERNS ON THE ...

The relation between applied torque, T, and pre-tensioning load is;
Tk.F .d
Where d is the nominal outside diameter of the bolt and k is the correction factor that depends on the
material, size, surface friction, and threading of the bolt. For most small to mid size bolts, k is between
0.15 and 0.3. For dry (un-lubricated) mid-size steel bolts the k is approximation k=0.2
Required torque for 0.5 in bolt:
Where;
d0.5 in
F 12 kips
k0.2
T 0.2 12 kips 0.5 in 1200 lb. in 100 lb. ft
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