Guidelines for coefficients of frictions - steel fasteners

 
Standard finish of steel plated bolts
Surface condition µ total for lubricated condition
Screw Nut Oiled MoS2 paste
No subsequent treatment phosphated No subsequent treatment 0.12 - 0.18i 0.05 - 0.1
Electroplated approx 8U No subsequent treatment (electroplated 5U) 0.12 - 0.19i -
Dacromet coated 6-8u No subsequent treatment (electroplated 6-8U) 0.10 - 0.14 -
 

i For tightening with impact or mechanical screw driver µ total must be 0.125.