Manufacture of bellows-type seals

摘要

1,060,955. Turning. COMMISSARIAT A L'ENERGIE ATOMIQUE. Dec. 6, 1965 [Dec. 29, 1964], No. 51665/65. Headings B3B and B3T. [Also in Division F2] Bellows for expansion joints or seals are machined from a thick-walled tubular member of e.g. polytetrafluoroethylene by mounting the tubular member (Fig. 3, not shown) upon a mandrel, turning a succession of grooves in the outer face by means of a tool (38), each groove being supported after turning by the insertion of two half-washers (40) surrounded by a bushing (42) until all the required grooves are machined in that face. The individual bushing elements are replaced by a single tube (44) (Fig. 4, not shown) and the complete assembly placed over a stub mandrel (46) and the grooves on the inner face machined by means of a tool (48).