Patent GB-899600-A (GB)
Title: Apparatus for handling stands of well pipe
IPC: E21B19/20
Filed: 1960-04-29
Abstract: 899,600. Boring earth &c. DRESSER INDUSTRIES Inc. April 29, 1960 [May 25, 1959], No. 15127/60. Class 85. Apparatus for handling pipe to be lowered into or removed from well comprises a hoisting device, a pair of pipe elevators, supporting means at the base of the hoisting device adapted to support an elevator over the well, power operated means for moving the elevators alternately into or out of supporting engagement with a pipe section, and means for making and breaking connections between pipe sections. The invention is illustrated by a description of the handling of a drill string. Pulling of the string is commenced by lifting the string by the hoisting tackle 6 until the kelly (not shown) lifts the driving bush out of the master bush 41 of the turntable 4, and the first tool joint appears above the turntable. A stripper 69 and a plate 67 are seated on the bush 41 for rotation therewith, the plate carrying a movable portion 66 of tracks 56, 57. An elevator A with the gate 45 open is placed on the stationary part 68 of the tracks the seats 55 of the elevator engaging the faces 75 of the tracks. A latch 78 (Figs. 2, 9) is shifted by a ram 93 to engage a slot 77 in the plate 67 and prevent rotation of the plate and turntable. The elevator is shifted along the tracks under the surface 12 of the lower part 11 of the tool joint by a ram 84, the spring catch 90 of the ram engaging the cross-bar 65 of the elevator, and the gate automatically closing about the string. The ram 84 is contracted and the catch 90 disengaged. The string is lowered so that its entire weight is carried by (he elevator and the latch 78 is released. The kelly is held against rotation, the tool joint is broken by rotating the turntable, and the kelly and its bush are lifted out of the way by the swivel 18. Links 20, 21 of the swivel are engaged in slots 50 of an elevator B which is then lifted to lie on the axis of the elevator A The elevator B is lowered and guided by a runner 106 sliding on a cable 99. Whilst the elevator B is still a considerable distance above the table a ram 96 is contracted to operate an eccentric 101 to tighten the cable so that further lowering deposits the elevator B on the stationary part 68 of the tracks (see Fig. 1). The seating of the elevator B on the tracks removes detents 60 from the slots 50 as that further lowering of the links disengages them from the slots. The ram 96 is permitted to extend to turn the cam and loosen the cable (Fig. 9) so that the links swing into alignment with the elevator A. On lifting the links engage the slots 50 of the elevator A so that the string may be lifted until the shoulder 12 of the next tool joint is positioned above the table. The plate 67 is fixed by the latch 78 and the elevator B is moved by the ram 84 to engage the string. The upper section of the string is held by tongs and the latch is disengaged to allow the turntable to spin loose the upper section. The upper section is stacked and the elevator A removed and lowered to the stationary part 68 where the detents are disengaged and the links freed to engage the elevator B. The remaining sections of the string are pulled and racked in a similar manner. During lowering a string into a well the links freed from an elevator supporting the part of the string in the well are swung to engage an elevator on the stationary part of the tracks by tightening the cable. The elevator on the stationary part is then used to lift an additional section over the well, the pipe being spun on to the string by locking the plate against rotation. The string is lifted by the upper elevator to permit removal of the lower elevator to the stationary part of the tracks by the spring catch. The string is lowered into the well to be supported by the upper elevator until another section is added. In apparatus for dealing with small strings, all part of the tracks are rotary.