Bolt with necked-down portion - has grooves running longitudinally through shaft and thread and has reduced cross=sectional area at shaft.

摘要

A necked-down bolt comprises a threaded section and a necked down shaft, whose load carrying cross-sectional surface is less than that of the threaded area. The cross-sectional area reduction includes reduction of several longitudinal or spiral grooves extending over the shaft and thread areas. The bottoms of the grooves are at a constant distance from the centreline and the top portions of the grooves are cut away at the neck. An odd number of grooves is symmetrically arranged around the circumference, so that each groove lies diametrically opposite a non-grooved area. USE/ADVANTAGE - Cost-effective mfr. of grooved bolt with necked-down portion.