Machine design; a manual of practical instruction in designing machinery for specific purposes, including specifications for belts, screws, pins, gears, etc., and many working hints as to operation and care of machines (1918)
Wallace, Ernest L · Chicago, American technical society · leaf 62
s F2nl = Pp (13) Friction, however, is always present; hence the ratio of the usefulwork (Pp) to the work applied (F2nl) is not unity as above re-lations assume. From numerous experiments on the friction of screwsand nuts, it has been found that the efficiency may be as low as 10per cent.… … Fig. 20. Square Thread pounds; or the initial tension is somewhat less than the tabular safeload shown for a 1-inch bolt, with S assumed at 10,000 pounds persquare inch. For shearing stresses the bolt should be fitted so that the bodyof the bolt, not the threads, resists the force tending to shear…
Machine design
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
