GB859753A - Wall scratcher for well bores - Google Patents

Abstract

859,753. Borehole scrapers. BORG-WARNER CORPORATION. Nov. 18, 1957 [Dec. 11, 1956; Oct. 22, 1957], No. 35908/57. Class 85. A well scraper such as described in Specification 701,540 comprises a collar 1 in two detachably connected sections 2, 3 to which wire fingers are secured at spaced intervals, the sections being slit at intervals to provide protruding ribs 5. These ribs 5 together with the intervening web portions 6 form slots receiving T-shaped elements 7, Fig. 5, to secure the fingers 12 in position. Bundles of wires 13 encased in a coil spring 14 with their ends protruding are bent to a U-shape to form the fingers 12, each pair of fingers so formed being held by a tab 20 struck out of the collar and bent over the web of the U. Each element 7 has a boss 10 which bears against a rib 5 and acts as a spacer for the fingers 12, while the head of the element flexes the fingers 12 outwardly of the collar. The elements 7, which have seats 21 for the fingers 12, are preferably of flexible material such as rubber or neoprene and preferably the ribs 5 have indents 17 to grip the stems 8 of the elements 7. In a modification Fig. 7 the sections 2, 3 have hinges 31, 32 connected together by means of pins 34 and tabs 35 struck out of the sections are bent over the fingers 12 to secure them in position. Openings 36 formed by the struck-out tabs are enlarged to receive the bent portions of the fingers 12 and extend to a rib 38, which may be continuous throughout the length of the periphery of the collar 1 or may be interrupted and in each case flexes the fingers outwardly. Depressed seats may be formed in the rib 38 to receive the fingers 12.