GB439396A - Improvements in gripping and lifting devices for well casings, pipes and the like - Google Patents

Abstract

439,396. Gripping-devices for lifting well-casings &c. BYRON JACKSON CO., 2150, East Slauson Avenue, Los Angeles, U.S.A. Feb. 6, 1935, No. 3873. Convention date, Aug. 25, 1934. [Class 78 (iv)] [See also Group XXI] Gripping - devices, for raising well-casings, drill pipes, and the like, of the kind in which a pair of hinged members encircle the pipe or casing and are latched together at their free ends, are fitted with modified latching-mechanism arranged so that it cannot become unlatched by impact with the links of the lifting-chains, or otherwise by accident. Fig. 2 shows an elevation and Fig. 3 a plan of the front meeting edges of the appliance. The two hinged members each carry a supporting link 9 in a recess 8 ; the links being secured in position by turnup pivoted arms 10 secured by bolts 12. An interengaging lug and slot 36 on the two members prevent relative vertical movement under the strain of the load. The latch 33 is spring-pivoted on the shaft 17 on the one member and has a T-shaped front end provided with arcuate surfaces 15 engaging similar surfaces 16 on the walls of a recess in the other member. The spring 25 maintains the latch in its closed position unless it is opened forcibly by the handle 14<a>. The projecting ridge 30 prevents the link 9 from opening the latch by impact, while a projecting lug 32 prevents it from being struck by objects during its descent with the load. The projecting handles 5 protect it similarly during the raising of a load. In the main, the latch is mounted in recesses on the members so as not to project beyond the general contour of the apparatus. Specification 439,395 is referred to.