GB219370A - Improvements in or relating to means for raising casings, boring rods or tubes and the like from wells - Google Patents

Abstract

219,370. Marks, E. C. R., (Dunn Manufacturing Co.). April 16, 1923. Bore-hole apparatus. - Means for use in wells for lifting casings, tubing, or rods comprises hinged members adapted to embrace the casing &c. and connected to suspension means, and a spring-operated latch to lock the hinged members together, the spring tending to force the hinged members apart before they reach their fully closed position. In Fig. 1, members 1, 2, connected by a hinge 3, are locked by a latch 22 pivoted to the member 1 and engaging a nose 28 on the member 2 under pressure from a spring 26. The nose 28 has a curved part 31 engaging a part 32 of the latch when the members 1, 2 are only partially closed, the reaction between these surfaces, under the pressure of the spring 26, tending to force the members 1. 2 apart. Handles 29, 30 are provided on the latch and member 2 respectively. In Fig. 3, the members h, j, are connected by a pivot pin 39 which may carry a spring tending to force the members h, j apart. A latch 42 pivoted to the member j is pressed by a spring 47 into a recess 40 in the member h; when the members h, j are only partly closed, the spring 47, forcing the latch against the member h, tends to force the members h, j apart. A shaft carries a projecting arm 55 and may be turned by a pivoted handle 62 to cause the arm 55 to move the latch out of locking position; the pivoted handle 62 may be held in inoperative position by engagement with a projection on the part h.