US 3857450 A
A rotary drilling rig has the traveling block suspended from the crown block. A gear case is connected to a hydraulic swivel, a sub extended from the swivel through the gear case and connected to a sprocket which at the end of a gear chain extended from a drawworks. The gear case and swivel are both suspended from the traveling block to remain aligned with the bore hole during drilling and tripping. An elevator is suspended from the gear case at the end of pivoted bails to pick up pipe from a rack and move it to the bore and remove pipe from the string for racking. The elevator, suspended from bails is positioned with piston-cylinder motive means with which the action of the elevator can be automated.
Description (OCR text may contain errors)
Guier Dec. 31, 1974 DRTLLTNG APPARATUS  Filed: Aug. 2, 1973  Appl. No.: 384,802
 US. Cl 1.75/85, 175/207, 173/163  Int. Cl E211) 119/06, E2lb 19/16  lField of Search 175/85, 52, 207, 203;
 References Cited UNITED STATES PATENTS 8/1951 Binney 175/85 10/1960 Mistrot 175/85 X 3,776,320 12/1973 Brown 175/85 X Primary ExaminerDavid H. Brown Attorney, Agent, or Firm-Arthur L. Wade 5 7] ABSTRAUT A rotary drilling rig has the traveling block suspended from the crown block. A gear case is connected to a hydraulic swivel, a sub extended from the swivel through the gear case and connected to a sprocket which at the end of a gear chain extended from a drawworks. The gear case and swivel are both suspended from the traveling block to remain aligned with the bore hole during drilling, and tripping. An elevator is suspended from the gear case at the end of pivoted bails to pick up pipe from a rack and move it to the bore and remove pipe from the string for racking. The elevator, suspended from balls is positioned with piston-cylinder motive means with which the action of the elevator can be automated.
6 Claims, 11 Drawing Figures Patented Deco 31, 19M 3,857,450
4 Sheets-Sheet l Patented Dec. 31, 1974 I 3,857,450
4 Sheets-Sheet 2 Patented Dec. 31, 174 3,857,450
4 Sheets-Sheet 3 Patented Dec. 31, 1934 31,857,450
4 Sheets-Sheet 4 DR/L L lNG SEQUENCE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to positioning drill pipe in relation to the bore hole during the drilling and tripping operations. More particularly, the invention relates to the structure, the arrangement and the operation of the hoist equipment, hydraulic equipment and rotative power source for the string so this equipment will be kept in bore alignment while the pipe is moved to the bore, positioned in the bore and removed from the bore.
2. Description of the Prior Art The rotary drilling of wells began about the turn of the century. The motive power in and about the rig centered in a drawworks. The rotary table was geared to the drawworks to turn the drill pipe having the bit on its lower end. Tongs were manually operated to make and break the pipe joints. A rope was wound about the pipe, and a cathead, to spin the pipe.
After the pin was stabbed in the box, during the sequence of adding pipe to the string, the rope was used for the fast initial make-up of the pipe, preliminary to tonging. In the break-out sequence, the pipes were usually spun out with the rotary table after the tongs broke the joint. These tools were first used in this combination to drill a well in the Spindletop Field near Beaumont, Texas in 1901.
By 1912 the kelly, kelly drive bushing and tapered slips had been added to the rotary table. The amount of manpower, and methods of handling the tools, had been established. The number of men regarded as necessary on the drilling rig, and their way of operating the tools, has remained basically unchanged to this day.
The equipment, and methods of using the equipment, have fundamentally remained static from the early l900s. The inherent dangers to which the roughneck is exposed are now legend. The combination of movements in the cluttered and mud-slick environment must be highly disciplined. The slightest relaxation of attention, posture or timing will result in a wide variety of injuries, or even loss of life. The spinning chain, which was introduced in the early 1920s as a replacement for the rope of Spindletop, has prevailed to this day. It is infamous for the injuries it has caused and the lives it has cost.
All of the equipment of the rig has grown in size and complexity as well as having been sunk deeper. Drilling has become more costly. The wages of the manpower have increased. All the costs of making holes have literally soared. In the face of mounting expenses, wells are drilled in much the same way they were when rotary drilling first started.
There have been some elaborate plans to improve the tools and methods. Slips have been powered. Tongs have been mechanized. In addition to individual tool automation, giant machines have been developed under experimental conditions to bring all the operations together. By and large, these machines have been too complicated and sophisticated for the oil field conditions outside the experimental environment in which they must be operated and serviced.
Now the so-called Energy Crisis has captured contemporary news, and activity related to fossil fuels is being given attention. Drilling for these fuels is under investigation. The pressure is on to upgrade the drilling-make it less costly. There is even evidence of panic.
The drilling problem should not be aggravated by hurried and superficial assessment of the tools now in use. Careful attention should still be given to all present equipment before a decision is made to obsolete and replace any tool or combination of tools. The old tools should still be given every respect. They may be far from ideal, but they are standard on all rigs today. They are simple, rugged and require little servicing. They, and their parts, are standard throughout the world. F urther, they are operated in ways common to all regions.
From examples of the old equipment, some logical steps will be examined which have already been taken to improve the equipment. Guier U.S. Pat. No. 2,946,464 either discloses, or indicates, some of the original tool combinations with the standard hoisting equipment. Also, this disclosure represents early struggles to keep the pipe lined up with the bore while tripping in and out of the hole.
Guier U.S. Pat. No. 3,063,519 discloses a means of substituting pipe-handling elevators for slips to support the pipe while it is wrenched. The dual-elevator system is in current use on the Glomar Challenger" research vessel. This vessel is used for the deep sea drilling project of the Scripps-Howard Institute of Oceanography which is under contract to the National Science Foundation. This activity is what remains of the wellpublicized Project Mohole.
These developments evidence the unique and logical approach to improvments in drilling. The design parameter followed is to first use a sub-system approach. Thus tools can be saved or altered that are presently in service on 99 percent of all on and off-shore rigs. Second, there is eliminated all those dangerous and superfluous tools that crowd, or clutter, the congested working area where the activity is intensearound the well bore during drilling and tripping the pipe.
Another example of this common sense approach to improvement is disclosed in Guier U.S. Pat. No. 3,514,822. The transporter disclosed covered by the patent is to cooperate with the existing, traditional form of manual slips. This transporter reduces manpower on the rig floor and increases safety while greatly simplifying the use of a tool familiar to the rig worker.
The great leap forward in this sequence of events came with the GUlER-O-MATIC S-S-T-R (Stabber- Spinner-Tonger-Racker). The basic sub-assemblies of this system are disclosed in Guier U.S. Pat. No. 3,308,691; Guier U.S. Pat. No. 3,533,516 and Guier U.S. Pat. No. 3,703,l l 1. This machine breaks the longstanding accident cycle which has existed on the floor of the rig. Real progress has been made in reduced manpower, improved efficiency and increased safety.
The S-S-T-R fits neatly into the long familiar pattern of the rotary drilling system. It can be used with manual slips, with or without the transporter. It can also be used with completely powered forms of slips as well as the dual elevators. Whatever form of pipe handling system is used, the SS-T-R makes and breaks the joints, spins the pipe together and apart and helps to move the pipes toward and from their rack.
The S-S-T-R has made such marked advance in the drilling art, it deserves the emphasis of listing the equipment replaced.
1. Spinning chain.
2. Spinning cathead and breakout cathead.
3. Manual tongs (back-up and lead).
4. Tong back-up posts and snublines.
Further, in offshore drilling, additional equipment is replaced.
5. Kelly spinner and associated air equipment and hoses.
6. Attachments for mouse holes.
7. Two or more deck hoists (air tuggers) which are an aid in handling drill collars and in making mouse hole connections when seas are high.
8. Tong latch posts.
It is true that other machines have been developed which purport to carry out the functions of the 5-5-- T-R. However, none of these other machines has proved to be as compact and compatible with existing rig equipment. Further, none opens the door and lays the background for the next breakthrough achievement which will simplify the handling of drill pipe and associated functions. Now the art is ready for the next problem. It can now solve the problem of eliminating:
I. The rotary table.
2. The kelly.
3. The kelly drive bushing.
4. The mouse hole and rat hole.
SUMMARY OF THE INVENTION A principal object of the invention is to handle and transport pipe to the bore and from the bore hole in rotary drilling so as to eliminate the need for both a rat hole and a mouse hole.
Another object is to keep the source of rotative power and the hydraulic swivel in line with the bore hole and below the traveling block which pipe is added to, and removed from, the drill string during both drilling and tripping.
Another object is to combine the hydraulic swivel and gear train from the drawworks so the combination can be suspended below the traveling block and permit the pipe elevator to be suspended below the combination.
Another object is to support the elevator suspension below the swivel-gear train and automate the suspension so the elevator can pick pipe from the rack and return pipe to the rack without vertical deviation of the swivel-gear train.
The invention contemplates mounting the hydraulic swivel below the traveling block and extending its sub through a lower connection with a gear train to make up and break off with the drill string when desired during drilling and tripping. An elevator is suspended below the gear casing of the train connection with the sub so it may be pivoted out of line with the bore hole to transport pipe to and from a rack position.
The invention further contemplates the elevator suspended from bails pivoted from the gear casing and controlled by hydraulic piston-cylinder combinations in transport of pipe.
The invention further contemplates the drawworks connected to the swivel sub through a vertical bar having a sliding fit with a sprocket in the gear chain, which arrangement permits vertical in-line travel of the swivel and gear case linked to the vertical bar.
Other objects, advantages and features of this invention will become apparent to one skilled in the art upon consideration of the written specifications, appended claims, and attached drawings, wherein;
FIG. 1 is a perspective elevation of hoist apparatus about and above a bore hole and within a derrick in which the invention is embodied;
FIG. 2 a front elevation of a portion of the structure of FIG. 1;
FIG. 3 is a sectioned plan view of structure of FIG. 2 along 3-3 of FIG. 2;
FIG. 4 is an enlarged sectioned elevation of part of the structure of FIG. 3 along 44 of FIG. 3;
FIGS. 5A,'5B and 5C are somewhat diagrammatic representations of the drilling connections sequence; and
FIGS. 6A, 6B, 6C and 6D are representations of the tripping sequence.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, there is shown drilling apparatus as it is mounted within a derrick and over a bore hole. All of this structure has the drill pipe as its focal point. The end function is to rotate the drill pipe to make hole and remove and insert the drill pipe in sections as may be required.
The upper end of the drill pipe sections is shown at 1, extending up from the bore hole. Slips 2 are wedged between the pipe and slip spider 3 to suspend the pipe in a fixed position when it is disconnected from the hoist.
All of this drilling structure is oriented about vertical rails which are extended up from the floor of the derrick. Specifically, rail 4 and rail 5 are mounted solidly on the floor, parallel to each other, and with the bore hole between them. The upper ends of these rails are deliberately not shown, extending up beyond the view of FIG. 1. Of course, those upper ends are solidly supported in the overhead derrick structure.
None of the derrick structure is shown, but it is capped by the usual crown block through which cables run down to suspend traveling block 6 above the bore hole. Traveling block 6 is attached to a frame 7, journalled to travel vertically between rails 4 and 5. The hoist, formed by a draw works attached to the cable and the blocks of the derrick, raises and lowers the guided frame 7 to desired vertical positions.
FRAME 7 The frame is guided by the rails to travel vertically, directly in alignment with the bore hole. Particular note is made of this fact that all of the equipment to manipulate the drill pipe is mounted on the frame 7. By manipulation is meant the pipe is removed from its racks and inserted into the bore hole,'or removed from the bore hole and placed on its racks. Included is the suspending of the pipe sections while they are spun together and tonged or their connections broken and spun apart. All of these operations are carried out while the equipment mounted on the frame is kept in precision alignment with the bore hole. The equipment movement is very efficient and very few personnel are required to handle the drill pipe with this embodiment of the invention.
The frame 7 could be given several different specific forms within the scope of the invention. In the drawings it is shown to have upper and lower platforms. Platforms 8 and 9 can be defined as horizontal beams extended between the rails.
The platforms are in a common vertical plane. They are tied to each other by links 10 and 11 which are vertical and parallel to the rails and pivoted in their connections to the platform-beams. The pins of the pivot connections can be readily removed when it is desired to separate the platforms to service, repair and replace equipment mounted on the platforms.
The traveling block 6 is connected to the upper platform, supporting it from the crown block above. Therefore, the entire frame 7 is depended from the crown block: As the cable sheaved over the blocks is taken up and let out by the drawworks the frame is moved up and down to require positions between the rails.
On lower platform 9 is mounted swivel 12 through which drilling mud is supplied the drill pipe. The hose connection from the slush pump is only indicated to a limited extent. This system is only accessory to the embodiment of the invention and is sufficiently represented by the swivel. However, sub 13 is shown extending from the swivel down through platform 9 and into alignment with drill pipe 1.
Essentially, sub 13 is a sectioned conduit, or pipe, mounted to rotate within swivel 12. The lower end of the sub 13 connects to the drill pipe and conveys drilling mud from the swivel into the drill pipe. In the drawings, the threaded lower end of sub 13 is kept in precise alignment with the box 14 of drill pipe 1. Moved vertically on the rails, the swivel sub is made up to, and broken from, the box on the upper end of drill pipe represented at l as required in the drilling operations.
POWER TRAIN In addition to conveying drilling mud to the drill pipe, the sub is a part of the power train extending from the drawworks with which the drill pipe is rotated. The gear train terminates at an intermediate section of the sub 13, and the power of the drawwork is applied through the train to rotate the sub and the drill pipe connected to the sub at any point in the vertical travel of the sub over the bore hole.
FIG. 2 is an elevation which depicts the structure of FIG. 1 from an angle which shows the sub 13, swivel 12 and drill pipe 1 more clearly in their relationships. The sub 13 extends up into the swivel and comprises a number of sections. At an intermediate section, this sub is connected to the end of the gear train within platform 9.
FIG. 3 is a section of FIG. 2. This plan view shows more of the gear train. A sprocket is mounted on the sub 13. A similar sprocket 21 is mounted on power bar 22. Power bar 22 is rotated by the drawworks and results in sub 13 rotating at the end of this gear train.
FIG. 4 is a greatly enlarged, partially sectioned, elevation of platform 9 in the direction of 4-4 in FIG. 3. This view shows chain 23 in position over sprockets 20 and 21. Sprocket 20 is keyed to its intermediate section of sub 13. Sprocket 21 is vertically slideable along bar 22 and rotated by bar 22 to drive sub 13 through chain 23 and sprocket 20.
All of this gear train is mounted within platform 9 which has the specific form of a shell-like structure. The chain 23 extends out into an attached side section to reach sprocket 21. This extension is referred to as gear case 24. It is essentially a sub-shell of platform 9 to house the chain and support the sprocket 21 of bar 22.
UNDISCLOSED STRUCTURE The disclosure does not include many of the devices, implements, tools, etc. which are desirable and necessary to the drilling operations. For example, the tongs and spinners required to make up, and break, connections between sections of drill pipe have not been shown. All such structure has no direct bearing on embodying the present invention.
DISC LOSED STRUCTURE The present invention centers about those tools moved vertically over the bore hole. The frame 7 carries these tools in precision alignment with the bore hole and includes a portion of the power train from the drawworks to the drill pipe. Invention is then embodied in the structure which brings drill pipe into alignment with the bore hole. The invention carries out these functions by swinging only an elevator in an are from a pivot on the frame 7. All other equipment mounted on the frame is maintained in bore hole alignment. This arrangement results in very simple movements about the bore hole, on the floor of the drilling rig. Also, a result is an almost completely automated drilling operation requiring a minimum of personnel. Both drilling and tripping times are greatly reduced, compared with the times required by prior art equipment.
DRILLING CONNECTION SEQUENCE Referring to all of the drawings, but more specifically FIGS. 5A, 5B and 5C, the drilling connection sequence with the invention is disclosed. The elevator 30, as a tool suspended from frame 7, is carried through an arc in performing its function. FIGS. 5A, 5B and 5C are views selected to drammatize the relationship between the elevator and the drill pipe as a section of the pipe is removed from a rack and attached to the end of the drill pipe in the bore hole.
Elevator 30 is pivoted from bracket 31 on the underside of lower platform 9. In FIGS. 1 and 2 a pair of bails 32, 33 are disclosed as pivoted from platform 9 to support elevator 30 from opposite sides. Each bail is provided a separate pivot point and a separate motive means in the form of a fluid powered cylinder and piston. Other arrangements are practical. A cross link between the two bails could be provided and a single piston-cylinder link extended from the platform to the cross link. Therefore, both bails could be pivoted by a single pistoncylinder combination.
It is in view of these modifications which could be made to the specific arrangements of FIGS. 1 and 2 that the disclosure of FIGS. 5A, SB and 5C has been formed. Bail 32 is in view, linking bracket 31 to elevator 30. Bail 33 is behind bail 32 in this view. Pistoncylinder 34 is viewed extending from bracket 35 on platform 9 to bail 32. A second piston-cylinder could be directly behind 34 or piston-cylinder 34 could be cross-linked to both bail 32 and 33 as contemplated supra. In either event, piston-cylinder 34 is viewed as controlling the are through which elevator 30 is pivoted from bracket 31.
In FIG. 5B bail 32 is represented in dashed line. This simplification gives more of a sight of sub 13 and pipe 1 which are aligned behind bail 32.
Bail 32 actually includes a piston-cylinder 36. It is the actuation of this piston-cylinder which establishes the effective length of bail 32. Bail 33 has a similar pistoncylinder which can be viewed in FIG. 1 and FIG. 2.
The conduits for power fluid to each of the pistoncylinder units are not disclosed. It is evident that a source of hydraulic fluid under pressure can be readily provided and connected to the cylinders to position the pistons as desired. To clutter the drawings with these conduits might actually obscure the invention.
We can now return to the function of the embodied invention disclosed in FIGS. 5A, 5B and 5C. Frame 7 platform 9 moves elevator 30 to the vertical positions required to add drill pipe sections in the drilling operation. At the same time elevator 30 is carried through its are about the pivot point of bracket 31.
The elevator is suspended from its bails so it can be faced to open to left or to the right as viewed in FIGS. 5 and 6. In the drilling sequence of FIGS. 5A, 5B and 5C, the latch 37 faces to the right and hinge 38 to the left. In the tripping sequence of FIGS. 6A 6D the elevator 30 is turned over to face the latch 37 to the left, the hinge being to the right.
FIG. 5A can now be readily understood in the context of the following sequence FIGS. 5B and 5C. Sub 13 is made up to the drill string and has rotated the string and drill bit down to where it is time to add another section of pipe to the string in the hole. Pipe section 1 has been available on a rack not shown, but which held the pipe section 1 at the angle shown in FIG. 5A.
As the platform 9 has been lowered, the open elevator 30 has descended upon pipe 1 below its box 14. Slips are set about the string. Sub l3 and the string are ready to be broken and spun apart. Latch 37 has been manually actuated to close elevator 30.
Upward movement of frame 7 will now lift pipe 1 from its rack. When the lower end of pipe section 1 has been lifted above the upper end of the drill string in the bore hole, piston-cylinder 34 is powered to swing section 1 into vertical alignment with the string. FIG. 5B shows this vertical alignment.
Piston-cylinder 36 is then actuated to shorten the effective length of bail 32, stabbing the pin of sub 13 into the box 14. At the same time, the lower pin end of pipe section 1 is stabbed into the box at the upper end of the string. The sub 13 is then rotated to make up both joints. The elevator 30 is then unlatched and swung out of the way, to the left, away from pipe 1. The slips are removed and drilling resumes as shown in FIG. 5C. When the bore hole is again deepened the length of the newly-added pipe section 1, the sequence, beginning with that portion of the sequence represented by FIG. 5A, is repeated.
TRIPPING It is necessary, from time to time, to remove the drill pipe from the bore hole. The string is removed in sections of pipe and stored on a rack.
The string is then replaced in the bore hole. Its sections of pipe are removed from their rack and made up to each other to complete the string. The string, complete and replaced, drilling is resumed.
The removal of pipe is referred to as coming out of the hole. The replacement of the pipe is referred to as going in the hole. Together, the complete operation is termed Tripping." The pipe is tripped out the pipe is then tripped in. FIGS. 6A 6D are established to disclose the invention as it is used to carry out the complete tripping sequence.
The concept of the invention enables the embodiment to shift from the drilling mode to the tripping mode simply by turning the elevator 30 over in its bails. As a practical matter it is at this switchover that the prior art is defective. Many add-on tools to conventional drilling practices have been touted by their developers as saving drilling connection time and tripping time. However, the preparation of placing the tools to start each sequence often takes up more time than is saved by the add-on tools. With the present invention, all tools are in place for both drilling and tripping. Only elevator 30 must be rotated to face in the proper direction.
As in FIG. 5, the elevator 30 is simply carried through an are about the pivot of bracket 31 during all the sequences of tripping shown in FIG. 6. Carried through its arc by piston-cylinder 34 and vertically adjusted by the hoist of frame 7, elevator 30 is used to remove pipe sections from the string in the bore hole, rack them, unrack them and return them to the bore hole.
FIG. 6A shows pipe section 1 in position within the bore hole, ready to be removed and racked. Frame 7 has lowered elevator 30 to the position where it can be swung back to pipe 1 under its box 14. FIG. 6B shows section 1 after it has been raised high enough to clear the bore hole and been broken from the lower string. In FIG. 6B elevator 30 is being swung, with its pipe section, to rack the section. Elevator 30 will next be unlatched and pipe 1 ejected toward its rack. Other structure not in view may take over to specifically rack the pipe.
FIG. 6C is technically a duplicate of FIG. 6B. However, it shows the drill pipe section 1 having been removed from its rack and moved into the grasp of elevator 30. The elevator is latched and swung into bore hole alignment. The pipe 1 is then spun and tonged in make up to the drill string.
The slips are next removed from holding this pipe and frame 7 lowered as shown in FIG. 6D. Bail 32, and included piston-cylinder 36, are represented by a single dashed line, the better to view the alignment of the sub with the drill string. When the trip is complete, the sub will be made up to the upper end of the string and drilling resumed.
SUMMATION The foregoing disclosure of hoisted frame 7 and controlled elevator 30 from frame 7 embody a central core of the inventive concept. This handling, or manipulation, of the drill pipe in making drilling connections, and tripping, is a revolutionary development when the evolution of present day drilling techniques is understood.
Both rat hole and mouse hole have been eliminated. The swivel and kelly no longer swing dangerously over the derrick floor, pushed and pulled inefficiently by numerous personnel. The swivel is mounted on the stable frame 7 and carried in precise vertical alignment with the bore hole during drilling and as all connections are made and broken. Only the elevator swings out of bore hole alignment to bring pipe to the bore hole and remove pipe to a rack.
The off-set power train including bar 22 keeps the drawworks linked to the drill string while the swivel and its sub is positioned vertically over the bore hole. The kelly and rotary table are gone, the off-set power train substituted, with increased efficiency and great simplicity. The result is reduction in personnel and greater safety for the remaining personnel. Futher, great intervals of time have been saved throughout the drilling and tripping sequences.
HOISTING In addition to the use of frame 7 as part of the hoist required for drilling connections and tripping, there is its utility in moving other equipment at the site of the bore hole. This utility is a bonus which inherently descends to the user of the invention.
Equipment used to spin and make-up and break-out pipe connections needs to be hoisted for repair, service and replacement. The prior art arrangements have contemplated use of the traveling block for this function.
Frame '7 is always available as a sturdy link between the traveling block 7 and any lower equipment requiring vertical hoisting. The heavy slip spider 3 and any or all of the spinning and tonging equipment are examples of equipment which can be lifted by attachment to frame 7. Mounting brackets 40 represents structure which can readily be fixed to the underside of platform 9 for attachment to the equipment to be hoisted. Thus the structure embodying the present invention demonstrates another fit into the general pattern of functions required on the derrick floor. Rather than introduce the complications of so many add-on tools developed in recent years, the present invention either simplifies the required functions on the rig or does not further complicate them.
From the foregoing, it can be seen that this invention is one well adapted to attain all of the ends and objects set forth, together with other advantages which then become obvious and inherent to the apparatus in which the invention is embodied.
As there are many possible embodiments of the invention without departing from the scope thereof, it is to be understood that all matter set forth or shown in the drawings is to be interpreted in an illustrative and not in a limited sense.
The invention, having been described, what is claimed is:
1. A drilling rig structure, including,
a rail extended vertically adjacent a bore,
a frame arranged to be guided in vertical travel on the rail and over the bore,
a traveling block attached to the frame,
a drawworks connected to the traveling block so the drawworks can raise and lower the frame over the bore,
a swivel mounted on the frame and below the traveling block, the swivel arranged to be connected to receive drilling fluid from a source and deliver the fluid to a hollow sub,
a sub in the form of a hollow driving shaft mounted on the swivel so as to extend down into alignment with the bore and connect with drill pipe to deliver drilling fluid to the drill pipe while rotating the drill plpe,
a gear train extended to connect: the sub to the drawworks for selective rotation of the sub,
a bail pivoted by one end from and extending below the frame,
a power means connected to the frame and to the bail below its pivot point to move the other end of the bail through a predetermined arc,
and an elevator mounted on the lower end of the bail so the elevator is pivoted to latch about pipe and move the pipe into and out of vertical alignment with the bore for connection and disconnection with the sub without the remaining structure on the frame being moved from its vertical alignment with the bore.
2. The drilling rig of claim 1 in which,
the frame included an upper platform to which the traveling block is attached and a lower platform on which the swivel is mounted and from which the bail is pivoted and to which the power means is connected and on which the gear train is mounted to connect the sub to the drawworks.
3. The drilling rig of claim 2 in which,
support structure is mounted on the lower platform and arranged to coupled to any equipment about the bore which equipment requires hoisting by the power of the drawworks through the frame as a link.
4. The drilling rig of claim 2 in which,
links are provided to connect and pivot between the upper and lower platforms,
and the power means comprises a piston-cylinder combination connected between the lower platform of the frame and a pivot point intermediate the ends of the bail.
5. The drilling rig of claim 4 in which,
a second bail is pivoted from and extends below the frame,
and a connection is provided between the second bail and the power means to that both bails are pivoted together by the power means with the elevator mounted on the lower ends of both bails.
6. The drilling rig of claim 5 including,
a piston-cylinder as a part of each bail so the distance between the ends of the bails may be changed to separate the sub and drill pipe after their connection has been broken.