Patent GB-560024-A (GB)
Title: Improvements in and relating to well drilling apparatus
IPC: E21B3/06
Filed: 1942-06-19
Abstract: 560,024. Valves. OIL WELL ENGINEERING CO., Ltd., and NATIONAL SUPPLY CORPORATION (National Supply Co.). June 19, 1942, No. 8460. [Class 135] [Also in Group XXI] Relates to rotary well-drilling rigs and comprises mainly control means for the drawworks winding drum and the rotary machine to facilitate high speed operation in making up or breaking down the drill string. The plant comprises a motor C, Fig. 1, a drawworks B and the rotary machine A ; the motor drives a drive shaft 22 from which a jack-shaft 21 is driven at high speed through clutch 35 and chain gearing 27, 33, at inter-, mediate speed through chain gearing 26, 32, and clutch 34, at low speed through chain gearing 25, 31, and clutch 34, or in the opposite direction through gears 28, 29 and clutch 30. The jackshaft 21 drives the line shaft 4 through high and low speed chain gearings 36, 38, and 37, 39, controlled'by a common spline clutch 40. The line shaft may drive the winding drum 11 at low speed through a spline clutch 46, chain gearing 41, 43 and a friction clutch 9 ; alternatively, through a friction clutch 8 comprising a spider 54, Fig. 10, with a fixed wall 55 and a disc 56 adapted to be engaged with friction discs 53 by means of a clutch plate 57, the line shaft may drive chain gearing 42, 44, driving a sleeve 48,. Fig. 11, carrying a spline clutch member 10 adapted for engagement either with a clutch member 75 to drive the winding drum 11 at high speed, or with a clutch member 72 connected by drivers 71 to a sprocket 49 from which the rotary machine A is driven. The winding drum 11 is provided with band brakes'14 and is also connectible through a self-aligning coupling with a fluid brake 16. The line shaft may also, through clutch 86 and chain gearing 85, 84, drive a catshaft 12 carrying an automatic cathead 83 and an ordinary cathead 13. Interlocking controls for the clutches 8, 9, and coupling 10 comprise a bell crank lever 101, Fig. 7, operated by a lever 92 and connected to the coupling 10 and also, through links 104, 105, to a valve 106. In the position shown, the coupling 10 connects the clutch 8 to the drum 11, depression of a treadle 87 admits air from a main 93 through valve box 95 and valve 106 to cylinder 94 to actuate clutch 8, while depression of treadle 89 admits air through pipe 111 to operate clutch 9, and depression of treadle 88 acts through co-operating lugs on the treadles to return the valves in box 95 to closed position. On moving lever 92 to put coupling 10 into driving engagement with the rotary machine A, the valve 106 is cut off from box 95 and opened up to box 96 with treadles 90, 91, adapted respectively to admit air to cylinder 94 'to operate clutch 8, and to cut off said air supply. The valve box 95 comprises valves 123; Fig. 16, slidable on members 131, 132, to control communication between the air supply pipe 93 and outlets 108, 111, the valves having grooves 122 engaged by fingers carried by a pivoted member 119, Fig. 15, the member 119 being rocked by fingers 115, 116, actuated by the treadles 87, 89, to open one or other of the valves 123, and being held in adjusted position by a spring-pressed plunger 124 co-operating with notches 125. The valve box 96 contains a single valve similar to valves 123 and actuated by treadles 90, 91, through a pivoted member similar to member 119.