GB523992A - Improvements in and relating to rotary drawworks for well and like drilling plant - Google Patents

Abstract

523,992. Well &c. drilling, plant. NATIONAL SUPPLY CORPORATION, and OIL WELL ENGINEERING CO., Ltd. Jan. 18, 1939, No. 1807. Convention date, Jan. 18, 1938. [Class 85] In a rotary drawworks for well &c. drilling plant comprising a drum mounted on a shaft, and a countershaft parallel to the drum shaft and carrying means such as a sprocket adapted to drive the rotary machine, a driving and a driven member are mounted on the drum shaft and countershaft respectively, and clutch means are provided for releasably connecting said members to their shafts for driving either the drum shaft or the countershaft or both. A prime mover 2 drives a line shaft 10 adapted to drive a cat shaft 11 through chain gearing 15 and a clutch 16 on the cat shaft, and also adapted to drive the drum 20 through either of three variable-speed chain transmissions 12, 13, 14, and clutches 17, 18, 19, on the drum shaft; the drive 14 also drives a sprocket 27 on the drum shaft, which sprocket is adapted to drive a low countershaft 21 through chain gearing and a clutch 29 on the countershaft. A sprocket 30, adjustably keyed to the countershaft, drives the rotary table 3 through a chain. An extension shaft 35, carrying a sprocket 33, may be coupled to the countershaft 21 whereby the rotary table, after being moved laterally, may be driven to bore a " rat hole" for support of the Kelly and swivel. A multi-speed drive may be provided for the rotary table. Separate enclosures 38 ... 42 are provided for the various chain transmissions. In a modification, the drive 14, and the drive to the countershaft 21, are arranged between the drum 20 and the drawworks post 7.