EXPANSION BOLT Russian patent published in 2002 - IPC

FIELD: mechanical engineering; fasteners for spot split and non-split joints. SUBSTANCE: proposed expansion bolt has body with head and point. Body is made round, oval or elliptical in form. Length of body is chosen within 5 and 22.6 of its maximum diameter. Diameter of expansion bolt head is chosen within 1.2 and 3.6 of maximum diameter of body. Point of body is curvilinear, conical or pyramidal, or combination of indicated shapes. Length of point on expansion bolt body is chosen within 1.28 and 3.4 of maximum diameter of body at its point. Hardness of expansion bolt after thermal treatment is within HRC_s = 45-60. surface of expansion bolt body is knurled, length of knurling being 0.25-1.0 of body length and pitch, within 0.03 and 0.52 of maximum diameter of expansion bolt body with depth of knurling within 0.02-0.15 of maximum diameter of body. Washer is fitted on expansion bolt body. Outer diameter of washer is chosen from 2.2 to 5.4 of maximum diameter of expansion bolt body. EFFECT: provision of high reliability at driving into concrete, brick or sheet metal, improved load bearing capacity and strength. 4 cl, 3 dwg