Spherical washers / Conical seats are used as washers in a screw connection to compensate non-parallel surfaces.
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1) Torques of screws 8.8, eventual pre-loads to be conisdered, coefficient of friction µtotal 0,14.
2) DIN standards do not include these dimensions.
3) Figures theoretically determined
Conical seats form D are to be used only for plain, closed round areas.
For larger holes only use form G!