Patent GB-603641-A (GB)
Title: Improvements in and relating to consolidated rigs for drilling wells or boreholes
IPC: E21B3/06
Filed: 1945-07-30
Abstract: 603,641. Drilling wells &c. NATIONAL. SUPPLY CORPORATION, and OIL WELL ENGINEERING CO., Ltd. July 30, 1945, No. 19491. Convention date, July 29, 1944. [Class 85] [Also in Group XXIV] Plant for drilling wells or boreholes comprising a draw-works, including a driven line shaft driving a drum shaft, a brake, and clutch means providing a releasable coupling between the line shaft and the brake such that the brake is selectively operable to resist rotation of the drum shaft independently of the line shaft. Drilling plant.-The draw-works B comprises a line shaft 5 carrying a sand reel 11 and driven through a multi-chain drive 14 ; the line shaft may drive a drum shaft 4 at low speed through a multi-chain drive 17 and loose sprocket 18, or it may drive through a pneumatic clutch 23 and a multi-chain drive 20 a loose sprocket 21 which, through a clutch 22, may either impart a high-speed drive to the drum shaft or drive the rotary machine A. A hydraulic brake 25 may be connected by a clutch 98 to the housing of the clutch 23 to resist rotation of the drum shaft ; the clutch 98 has sufficient displacement provided to permit repairs and renewals of the clutch 23 without removing the brake. A cathead shaft 6 is driven through chain gearing 27, 28. The draw-works is driven through a transmission unit C comprising a driven shaft 29, an intermediate shaft 30 and a drive shaft 31, low, medium and high speed drives 36, 37, 38, and a reverse drive 39 being provided. The shaft 29 may be driven by any or all of the internal combustion engines 33 . . .35 through a pneumatic clutch 32, the engine 33 being detachably connected to the clutch housing which is fixed to a sprocket 45 to which the drive from engines 34, 35 is communicated through multi-chain gearings 43, 44, and clutches 54, 59. The engines also drive mud pumps 48, 49, through pneumatic clutches 59, 64, and multi-belt transmissions 66, 67 ; if high pressure is required, pump 49 is driven at low speed through chains 69 and pneumatic clutch 71. Clutches.-The clutch 23 comprises a housing 72, Fig. 7, supported on bearings 74 on the shaft 5 and carrying clutch rings 80, 81, co-operating with faced clutch rings 84, 85, carried by a spider 77 fixed to the shaft 5 ; the clutch is applied by fluid supplied through a conduit 94 extending through the shaft 95 of brake 25 and acting on a piston 82 bearing on the clutch rings. The clutch 32 comprises a spider 103, Fig. 4, held to the tapered end of the shaft 29 by a ring 104 and splined to clutch rings 129 arranged on opposite sides of a clutch ring 125 which, with a piston 115, slidably engages bolts 124 connecting the housing ends 122, 126. Air is supplied through a port 121 in shaft 29 to act on piston 115 to apply the clutch, while springs 128, arranged on pins 127, urge the clutch into disengaged position ; if the air supply fails, the clutch may be applied by threaded studs 136. The piston 115 has a removable central part 118 giving access to packings &c. in the clutch. The clutch housing is detachably connected to the engine shaft 40 through splined coupling collars 107, 108, and a spacer ring 113 of such width that, when removed, repair &c. of the clutch may be effected.