Method Of Handling Drill Pipe

Abstract

As each successive stand of drill pipe is pulled out of a well hole at the bottom of an oil well derrick, it is set back in the derrick until a multiple stand set back has been formed. Then the lower end of the setback is swung out of the derrick and away from it while the upper end of the setback is being lowered. Substantially at the same time the setback is moved bodily, lower end first, away from the derrick to lay the setback down on a support.

Parent Case Text

This application is a division of our copending patent application, Ser. No. 25,644, filed Apr. 6, 1970, now U.S. Pat. No. 3,613,905.

Description

During the drilling of an oil well it is necessary to move the drill pipe into upright position in a derrick so that successive stands can be connected together to form the drill string. When the string is pulled from the well, successive stands are stood up at one side of the hole to form a setback. If the well is a deep one, the derrick may not be able to accommodate all of the stands, so some of them must be moved out of the derrick and stacked in some manner beside it. In the past, this has involved moving each successive stand individually, thereby requiring a considerable amount of time. Laying pipe down outside of the derrick also reduces the physical effort otherwise required of the derrickman in handling the upper ends of the pipe stands. In case drilling is being done from a floor floating on a body of water, an additional advantage in laying down pipe is that it relieves the derrick from inertial forces induced by wave action and aggravated by the great weight of the usual pipe setback.

It is an object of this invention to provide a method of moving drill pipe back and forth between a reclining position beside a derrick and an upright position inside the derrick. Other objects are to accomplish this rapidly and in as simple a manner as possible.

The invention is illustrated in the accompanying drawings, in which

FIG. 1 is a side view of our pipe handling apparatus in its upper position;

FIG. 2 is a front view of the apparatus;

FIG. 3 is an enlarged horizontal section showing a setback before the pipe handling apparatus is attached to it;

FIG. 4 is an enlarged fragmentary plane view of the elevator used with the apparatus;

FIG. 5 is a cross-section taken on the line V--V of FIG 4;

FIG. 6 is a fragmentary front view of the lower end of the upright strongback;

FIG. 7 is a fragmentary horizontal section of the strongback before it is clamped onto the setback;

FIG. 8 is a similar view after clamping;

FIG. 9 is a side view, similar to FIG. 1, of a modification;

FIG. 10 is a horizontal section of the modification, similar to FIG. 3;

FIGS. 11, 12 and 13 are views similar to FIGS. 1, 2 and 3, of a further embodiment of the invention; and

FIG. 14 is a side view of a rack for receiving pipe that is laid down outside the derrick.

Referring to FIGS. 1 and 2, an oil well derrick 1 is shown in outline mounted on a substructure 2. FIG. 3 shows that several stands of drill pipe 3 have been pulled from the well by the traveling block 4 in the usual way and set back on the derrick floor in front of the well, with their upper ends leaning against the working platform 5. While in this position, a special elevator 7 is connected to their upper ends as a group. This elevator is suspended from a sheave 8 at the top of the derrick by means of a line 9 that extends down to a winch 10 on the derrick floor. As shown in FIGS. 4 and 5, the elevator is a crossbar provided with a row of laterally opening recesses 12 for receiving the upper ends of the pipes. The tool joints 13 on the upper ends of the pipes extend above the bar and rest on it. The bar is provided with upwardly extended lugs 14 between the outer ends of the recesses, and the distance between these lugs is less than the diameter of the tool joints. The elevator is applied to the pipes a short distance below the tool joints and then raised until the joints rest on it. The tool joints cannot escape between the lugs. When the elevator is raised, it suspends the group of pipes or setback from it in vertical position as shown in FIGS. 1 and 2.

Spaced in front of the bottom of the substructure there is a suitable support 16, on which the inner or lower end of a bifurcated boom 17 is pivotally mounted on a horizontal axis parallel to the front of the substructure. The upper or outer end of the boom can be swung through an arc by means of a fluid pressure cylinder 18 and piston 19 pivotally connected to the bottom of the substructure and lower part of the boom. The outer end of the boom is pivotally connected to the central part of a strongback 20 that takes the form of a rectangular frame between the two sides of the boom. The opposite ends of the strongback are provided with means for attaching or clamping it to the pipe setback. When the boom is up and strongback is in vertical position beside the setback, the attaching means, pivotally connected to the boom by the strongback, extend toward the setback as shown in FIGS. 1 and 3.

As shown in FIGS. 6, 7 and 8, the attaching means or pipe clamping means include a row of fingers 22 provided with stub shafts 23 rotatably mounted in the top and bottom of the upright strongback frame. These fingers extend toward the back of the derrick and are in the form of blocks that are considerably wider than they are thick. Their shafts project from the front of the strongback and are rigidly attached to levers 24 that extend away from them in parallel relation. The outer ends of the levers are pivotally connected to a cross link 25, one each of which is pivoted to a bell crank 26 mounted on the strongback. The crank is also connected to a piston rod 27 that extends into a cylinder 28 pivotally attached to the side of the strongback. When the piston rod is extended as shown in FIGS. 6 and 7, the fingers are disposed on edge and can be inserted between the pipes. The piston rod is then drawn into the cylinder and that swings the levers to rotate the fingers 90.degree. so that recesses 29 in their opposite edges will receive the adjoining pipes and thereby clamp them to the strongback, although the pipes can slide lengthwise relative to it.

After the strongback has been attached to the suspended pipe setback, the boom is swung outwardly away from the derrick by means of cylinder 18, which causes the lower end of the setback to likewise swing outwardly. At the same time, the elevator 7 is lowered so that the upper end of the setback swings downwardly as its outer end swings forward as shown in dotted lines in FIG. 1. If the strongback slides along the pipes, it will stop when the upper row of fingers 22 reach a tool joint. As the boom swings outwardly, the lower end of the setback swings out through its central slot and the setback approaches a horizontal position that is reached by the time the boom reaches its lowest position. As the strongback descends, it deposits the setback on a suitable pipe rack 31 on the ground. The strongback is disconnected from the horizontal setback and the boom returns the strongback to its upper position for attachment to the next setback. This is repeated until all of the setbacks have been deposited in the pipe rack.

Since the pipe stands are handled in groups, one trip of the strongback from the derrick to the pipe rack on the ground carries several stands, so the operation is greatly simplified and is speeded up. Another advantage of this apparatus is its simplicity. The strongback, being pivoted to the slotted boom in such a manner that it can swing through the boom, can deposit the reclining pipe setback on support 31 directly and then rise away from it. It is unnecessary to provide additional apparatus for lifting the setback from the strongback before the latter can be swung back up to upright position in front of the next setback.

When the pipe is to be run back into the hole to resume drilling, the pipe lay-down system described above is reversed. That is, the lowered strongback is attached to a row of pipe stands on the rack, and the special elevator is attached to the inner ends of the stands. Then the boom is raised as the winch raises the elevator, so the upper ends of the stands swing upwardly as their lower ends swing rearwardly until the stands are upright in the derrick. They are then lowered by the elevator 7 to set them on the derrick floor, after which the strongback clamps are released from them and then a manipulating arm 32 moves the upper end of the setback to the side of the platform 5 as indicated in FIG 3. The elevator then is disconnected from the setback.

In the embodiment of the invention just described the pipe stands that are carried by the strongback are disposed side by side in a straight row extending parallel to the strongback frame. In the modification shown in FIGS. 9 and 10, the setback 36, three rows of three stands each being shown. These rows are formed as each successive stand is pulled from the well by traveling block 37, set back on the floor of the substructure 38 and leaned against a working platform 39 by the derrickman. An elevator 42 similar to the one shown in FIG. 4, but having much deeper recesses, then is connected in the same way to the upper ends of the stands so that the group or setback can be lifted by line 43 from a winch 44 and suspended vertically directly in front of the well for gripping by a strongback 45. The strongback has a rectangular frame, the central portion of which is pivoted on a horizontal axis 47 to the upper end of a bifurcated boom 48. The lower end of the boom is pivoted on a support 49 projecting forward from the substructure, and the upper end of the boom can be swung out and away from the derrick by means of a fluid pressure cylinder 50 pivotally connected with the substructure and the boom.

The setback stands are moved by the elevator into slots between parallel fingers 52 extending rearwardly from the top and bottom of the strongback frame. These fingers are rotatably mounted in the frame in the same way as those shown in FIGS. 6 to 8 and also can be turned 90.degree. in the same manner to hold the pipe stands between them. After the strongback has been clamped onto the setback in this manner, the boom is swung outwardly and down as the elevator is lowered by the winch. This causes the lower end of the setback to swing out through the slot in the boom as the upper end of the setback is lowered, as shown in dotted lines in FIG. 9. The boom comes to rest when the setback is deposited on pipe racks 53 on the ground in front of the derrick. The fingers of the strongback then are turned 90.degree. to release the drill pipe, and the boom is raised to swing the strongback back up to upright position for attachment to another setback that can be formed while the first setback is being removed.

A still further arrangement is disclosed in FIGS. 11 to 13. Here the pipe stands 55 are arranged in a single row again, but the row is located in a vertical plane extending from front to back of the derrick 56. Another distinction is that instead of setting the pipe stands on the derrick floor as they are pulled from the well, they are set on a channel-like platform 57 at the lower end of a tall strongback 58. The platform extends toward the rotary table. Near the top of the strongback it is provided with a rearwardly extending long fork 59, as shown in FIG. 13, the sides of which are spaced apart just far enough to readily receive between them the row of pipe stands forming the setback. As each successive stand is placed in the fork, it is prevented from escaping by means of a latch 60 pivoted to one side of the fork and controlled in any suitable manner. There is a similar fork 61 and latch near the lower end of the strongback.

After the strongback has received a full load of pipe stands, it is swung forward away from the derrick by a bifurcated boom 63, to the upper end of which it is pivoted on a horizontal axis 64. The lower end of the boom is pivotally mounted in brackets 65 on the front of the substructure 66. As the upper end of the boom is swung away from the derrick by a fluid pressure cylinder 67, one way of controlling the position of the strongback is by a line 68 connected to the upper end of the strongback and passing over a sheave 69 at the top of the derrick and down to a winch 70 on the derrick floor as the line is let out, the upper end of the setback can swing rearwardly and down as its lower end swings up through the slotted boom. Everything moves downwardly until the strongback is horizontal and the setback is deposited by it in a pipe rack on the ground. The forks then are opened so that the strongback can be lifted away from the pipe in the rack.

The stands of pipe are fed into upper fork 59 when it is in its upper position shown in FIG. 13, by means of a hook 72 that is pivotally mounted on a slide 73 movable back and forth by a fluid pressure cylinder 74 connected to the strongback. When the slide is moved away from the strongback the hook strikes a stand suspended from the elevator 75 and the hook rotates to permit it to pass the stand. Then the hook swings out behind the stand and the slide is reversed to pull the hook and stand toward the fork until the stand can pass latch 60 and enter the fork.

Various kinds of supports or racks for the pipes can be used in front of the derrick, but a highly satisfactory one is shown in FIGS. 11, 12 and 14. Actually, there are two of these racks in spaced parallel relation. Only one needs to be described. It has a flat base 77 on which a carriage 78 provided with wheels 79 is mounted. The carriage can be moved along the base parallel to the front of the substructure by means of a screw 80 rotatably mounted in a stationary nut in the bottom of the carriage. The screw is driven by its outer end by means of a suitable motor 81. The carriage is provided with posts 82 arranged in two spaced rows extending lengthwise of the carriage. Most of the posts in each row are spaced apart only far enough to accommodate a drill pipe between them, the pipes between each pair of posts being stacked on top of one another. However, the spacing between the posts at one end of each row is wider in order to accommodate the larger diameter drill collars.

The carriage is moved along base 77 to line up the slot between a pair of posts with the center line of the strongback so that the strongback can deposit a row or stack or drill stands in the slot. As soon as the slot is filled, the carriage is moved a short distance to bring the slot into line with the strongback. This is repeated until all of the pipe stands have been deposited in the pipe racks. In returning the stands to the derrick for going back into the hole, it will be seen that each stack of stands in the pipe racks can be moved into a position to be straddled by the setback forks 59 and 61 so that the pipes can be picked up and returned to the derrick.

Claims

We claim:

1. The method of removing drill pipe from an oil well derrick and laying it down outside the derrick, comprising setting back in the derrick each successive stand of drill pipe as it is pulled from the wellhole until a multiple stand setback is formed, gripping the central portion of the setback, swinging said gripped portion of the setback out of the derrick and upwardly in an arc of a circle while lowering the upper end of the setback to cause the lower end to swing outwardly away from the derrick and upwardly, the center of said circle being below said arc, and continuing to swing said gripped portion of the setback away from the derrick and downwardly in a continuation of said arc while lowering the upper end of the setback faster than said gripped portion is lowered to thereby move the setback bodily away from the derrick and down into a substantially horizontal position outside the derrick, and receiving and supporting the substantially horizontal setback.

2. The method recited in claim 1, in which each successive stand of drill pipe pulled from the well hole is moved back between the preceding stand and the well hole to from a single row of setback pipe extending away from the hole.

3. The method recited in claim 1, in which each successive stand of drill pipe pulled from the well hole is moved back to form a row of pipe substantially perpendicular to a radius of the hole.

4. The method recited in claim 1, in which said stands of drill pipe pulled from the well hole are formed into a substantially rectangular setback.

5. The method recited in claim 1, in which said lowering of the upper end of the setback is controlled by a flexible line connected thereto and supported from the upper end of the derrick.