GB583187A - Improvements relating to the manufacture by rolling of annular articles - Google Patents

Abstract

583,187. Rolling annular bodies. BRASSERT & CO., Ltd., H. A., UDALL, W., and BOTTAMS, S. March 24, 1944, No. 5522. [Classes 83 (ii) and 83 (iv)] Making toothed gearing.-Annular articles such as wheels and the races of ball &c. bearings are produced by rolling blanks, having the grain extending parallel to the axis between internal and external rolls so shaped as to provide a closed pass at the end of the operation. In the production of hubs and rims for gearwheels, a blank cut transversely from the end of a circular section bar has a central hole punched and is then divided into two annular blanks, the inner being employed to produce the hub. This blank 24, Fig. 7, is mounted on the reduced end 28 of a roll 29 which is then advanced into the outer roll 35 and into spigot and socket engagement at 31 with a complementary roll part 30. The rolls are driven at related speeds and by relative lateral movement the blank is rolled out, the rolls forming a closed pass at the end of the operation. When the reduction of section commences, the drive to one roll is disconnected. A mill for carrying out the above operations is described in Specification 583,195. The roll 35 is in two sections 36, 37 to permit removal of the finished rings. Rings partly formed may be finished rolled or rings of finished shape may be rolled in the closed pass to alter the grain structure or produce surface hardening. In this case, the preliminary heating is carried out in an inert atmosphere. In rolling the outer blank, similar rolls are employed except that the neck 28 is grooved to form a rib instead of the roll 35. The wheel is completed by welding an annular web to the end ribs and is finished by cutting teeth and a keyway and by grinding. In a modification, when rolling the outer section, rolling is completed before the blank attains the diameter of the outer roll which is not then divided to permit removal ; centrifugal force being relied upon to maintain the circular shape.