Abstract:
A portable drilling rig including a carousel housing several drill pipe sections used in drilling oil, gas, or other wells into the earth. The carousel indexes the drill pipe sections as a mast raises and lowers a kelly, rotated by a top head. The kelly temporarily attaches to a stored drill pipe section and lowers it into the earth where the drill pipe section is connected to an existing drill string. This entire process is automated so that no human interaction with the actual drill pipe section is necessary. The entire carousel rig may be loaded onto a truck bed or other transportation device to be delivered to a site where drilling is to occur.

Description:
[0001]    This application claims priority in U.S. Provisional Patent Application No. 61/318,133, filed Mar. 26, 2010, which is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates generally drilling rig design as used in well drilling and in the production (e.g. oil and gas) industry, and more specifically to an automated drill-through carousel rig. 
         [0004]    2. Description of the Related Art 
         [0005]    As is generally known, underground petroleum reserves, water, and soluble minerals are accessed through vertical bores which extend downwardly through the earth. To create a vertical bore, a rotating metal tube having a leading bit or cutting element is penetrated through the crust of the earth&#39;s surface and is advanced downwardly until the tube reaches a bearing formation. The drilling string is then withdrawn from the bore and oil or other desired substances are pumped upwardly from the formation and through the bore with known extraction techniques. 
         [0006]    Generally, a flexible, rotary drill string is inserted through the vertical portion of an existing straight well bore. When the leading end of the drill string reaches the maximum available depth, a new length of drill pipe must be added to the drill string. The drill string is continuously advanced in this way by adding additional lengths of drill pipe. 
         [0007]    It may be understood from the foregoing that in order to create a suitable well bore a drill string must be advanced until the drill reaches a subterranean target, i.e. a bearing formation. Typically, additional drill pipe sections are secured onto the existing drill string using manual labor. Metal drill pipe sections are very heavy and awkward to handle, making the installation and operation of the drill pipe both cumbersome and dangerous. The extreme weight of metal drill pipe sections produces large friction forces when the pipe is rotated about an axis off vertical, such as when the pipe is used to drill a horizontal bore. This can create safety risks to the workers securing the drill pipe sections to the existing drill string. 
         [0008]    During the drilling of water, oil and gas wells, an elongated “string” of pipe is made up of separate sections of pipe. For example, drill pipe sections can be in lengths of 30 feet (9.1 meters) and casing is typically in lengths of 40 feet (12.2 meters) that are connected end to end as drill progresses into the earth. The lower end of the string carries a drill bit. These same sections of pipe are separated from the drill string one joint at a time when the drill string is removed from the well bore. 
         [0009]    Drill pipe sections can be stored (e.g. horizontally) on pipe racks next to the drill rig cat walk. Typically, the drill rig floor is at a considerably higher elevation than the pipe racks and cat walk. Drillers often face the problem of transferring drill pipe from the pipe rack to the elevated rig deck. 
         [0010]    One of the problems with the transportation of drill pipe is that of maintaining a proper orientation of the section of the drill pipe relative to the rig floor, especially when it is about to be either removed from the pipe transportation unit to the rig floor or transferred from the rig floor back to the pipe transportation unit. For example, it is important that the pipe be oriented in the correct position so that it can be elevated to lower the collar of the pipe directly into waiting pipe elevators. 
         [0011]    Another problem with the transportation of pipe racks to the drill floor is that the pipe is typically stacked in layers. This means that each layer must be unstacked one layer at a time. Pipe can be stacked many layers thick especially if the drilling operation is going very deep into the earth. 
         [0012]    A third problem with pipe transportation devices is that the drill pipe used in drill strings comes in a variety of widths and lengths. Systems that transport, store, and handle drill pipe sections must effectively support a wide range of drill pipe sizes. Heretofore there has not been available an automated carousel drill pipe storing and handling system and method with the advantages and features present in the current invention. 
       SUMMARY OF THE INVENTION 
       [0013]    It is an object of the present invention to increase the efficiency and safety aspects of typical terrestrial drilling rig applications. The present invention utilizes a carousel housing several drill pipe sections used in drilling oil, gas, or other wells into the earth. The carousel indexes the drill pipe sections as a mast raises and lowers a kelly, rotated by a top head. The kelly temporarily attaches to a stored drill pipe section and lowers it into the earth where the drill pipe section is connected to an existing drill string. This entire process is automated so that no human interaction with the actual drill pipe section is necessary. 
         [0014]    In the preferred embodiment of the present invention, the drilling carousel rig is compact enough to be loaded onto a flat bed truck or other transportation device. The rig is easily transported to the site where drilling is to commence. The rig may be righted on the back of the truck and drilling may proceed while the rig is still situated on the back of the truck, or the rig alternatively may be removed from the truck and positioned in a desired location. 
         [0015]    The carousel drilling rig is intended to be a unitary drilling rig containing the necessary drill pipe sections within the carousel housing itself The act of increasing the drill string, and thus the depth of the will, is automated. The only human interaction with the entire rig is with the control device that commands the mast, top head assembly, and hydraulic or electric motors driving the device. 
         [0016]    Typical drill strings are advanced by laborers manually adding a drill pipe section between the kelly and the advanced drill string. This is inefficient because the drill string must be hauled into position and safety concerns dictate that the drilling process proceed slowly to protect the laborers. By automating the drilling process, drilling is more efficient because safety concerns are not an issue and the drill pipe sections located in the carousel housing are automatically lined up to be added to the drill string. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    In the accompanying drawings, which illustrate the principles of the present invention and an exemplary embodiment thereof: 
           [0018]      FIG. 1  is an elevation view of an embodiment of the present invention shown in a starting position during a cycle. 
           [0019]      FIG. 2  is an elevation view of an embodiment of the present invention shown in action during a cycle. 
           [0020]      FIG. 3  is an elevation view of an embodiment of the present invention shown in an ending position of a cycle. 
           [0021]      FIG. 4A  is a plan view showing the carousel element of the present invention including the plurality of drilling pipe slots. 
           [0022]      FIG. 4B  is an enlarged elevation view showing the details of a single drilling pipe. 
           [0023]      FIG. 5  is an elevation view showing an embodiment of the present invention as being transported via truck. 
           [0024]      FIG. 6  is an elevation view showing an embodiment of the present invention as being deployed on a truck rigged for transport. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     I. Introduction and Environment 
       [0025]    As required, detailed aspects of the disclosed subject matter are disclosed herein; however, it is to be understood that the disclosed aspects are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art how to variously employ the present invention in virtually any appropriately detailed structure. 
         [0026]    Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, up, down, front, back, right and left refer to the invention as orientated in the view being referred to. The words, “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the aspect being described and designated parts thereof. Forwardly and rearwardly are generally in reference to the direction of travel, if appropriate. Said terminology will include the words specifically mentioned, derivatives thereof and words of similar meaning. 
       II. Embodiment of a Carousel Drill Pipe Handling Rig (Carousel Rig)  2   
       [0027]    Generally, the present embodiment is a carousel drill pipe handling rig  2  also referred to herein as a carousel rig. The present embodiment is generally preferable over the prior art because it requires less human labor, thus increasing safety and efficiency simultaneously. 
         [0028]    As shown in  FIGS. 1-3 , the carousel rig  2  is generally comprised of a carousel  4  housing a plurality of drill pipes  6 , a mast  7  separating the carousel from the tophead  8 , a floating sub  10 , a kelly  12  with a threaded connection end  14 , and a feed cylinder  16 . 
         [0029]    The carousel  4  holds several pieces of drill pipe  6  in a quasi-circular drum. The carousel  4  is rotated by mechanical means, such as a hydraulic or electric motor. The carousel is a “drill-through” carousel. The carousel rotates around the mast  7 , but otherwise does not move. Unlike previously used drill pipe carousels, the present embodiment does not include a carousel that swings in or out when making connections between pipe sections. The feed cylinder  16  is a hydraulic cylinder which provides pull-down and pull-back for the carousel rig  2 . The mast  7  passes through the cylinder and raises the tophead  8 , kelly 12 , and floating sub  10 . The kelly  12  is a drill pipe section that is semi-permanently affixed to the tophead  8 . The tophead provides rotation to the kelly  12  allowing the threaded connection end  14  to connect to proximal end  20  of drill pipe sections  6  contained in the carousel  4 , forming the kelly connection  30  between the drill pipe section  6  and the kelly  12 . 
         [0030]      FIG. 4A  is a top-down view of the carousel  4  showing the mast  7  passing through the center of the carousel  4  cylinder. Each of the several drill pipe sections  6  are contained within a number of drill pipe section storage chambers  9 . These storage chambers must be long enough and wide enough to contain a variety of different drill pipe section lengths and diameters.  FIG. 4B  shows a detailed view of a drill pipe section  6  including a proximal end  20  and a distal end  22 . In the preferred embodiment, the proximal end contains a threaded female connection and the distal end contains a threaded male connection identical to that of the threaded connection end  14  of the kelly  12 . 
         [0031]      FIGS. 1 through 3  represent the progression of the carousel rig  2  as the mast  7  raises, a new pipe section  6  is loaded onto the kelly  12 , and the new pipe section  6  is attached to an existing drill string and drilling continues, extended by the new pipe section.  FIG. 1  shows the mast  7  fully extended above the carousel  4 . The mast is raised by extending the feed cylinder  7 . The carousel  4  indexes, rotating to the next available drill pipe section  6 , and aligns the proximal end  20  with the threaded connection end  14  of the kelly  12 . From here, the mast lowers, bringing the threaded connection end  14  into contact with the proximal end  20  of the indexed drill pipe section  6 . The tophead  8  provides rotation which connects the kelly  12  to the drill pipe section  6  by threading the connection end  14  of the kelly  12  into the proximal end  20  of the drill pipe section. 
         [0032]      FIG. 2  demonstrates the mast  7  when it is halfway through the cycle down, bringing the new drill pipe section  6  into connection with an existing drill string (not shown) comprising a number of drill pipe sections connected together end-to-end. At this point, the advanced drill pipe section  18  has likely entered an existing drill hole (not shown). When the advanced drill pipe section  18  comes into contact with the existing drill string, the tophead  8  will again provide rotation, threading the distal end  22  of the drill pipe section into the receiving end of the drill string  26 , forming a drill string joint  28 . 
         [0033]      FIG. 3  demonstrates the mast  7  when it is fully through the cycle. At this point in the cycle, the advanced drill pipe section  18  has connected to the drill string  26  or a drill head and has progressed further into the earth. During connection to the drill string  26  and drilling into the earth, the floating sub  10  protects the tophead  8  by absorbing some of the shock associated with drilling and drill pipe make-up. The advanced drill pipe section 18  is advanced into the earth until the feed cylinder  7  is fully collapsed. From here, the tophead  8  rotates, breaking the Kelly connection  30  and detaching the kelly  12  from the advanced drill pipe section  18 , which is now part of the drill string  26 . The kelly can then be raised by raising the mast  7 , returning the system to the original starting position shown in  FIG. 1 , where the carousel  4  is then indexed and the process begins anew. 
         [0034]      FIG. 5  demonstrates an embodiment of the invention wherein the carousel rig  2  being transported by truck  24  in what is called the “road position.” In this position, the rig  2  is fully compacted, with the feed cylinder  7  fully compressed and the kelly  12  extending through an empty storage chamber  9  within the carousel  4 . This allows the entire drilling rig  2  to be transported to a desired location with ease.  FIG. 6  demonstrates the carousel rig  2  in an upright and ready position deployed on the back of a transport truck  24 . From here the carousel rig  2  can perform its job without being loaded onto additional equipment. The rig  2  may be raised on the back of the truck  24  by a hydraulic lift, an electric lift, or any suitable means. The rig may have to be rotated out over the end of the truck bed once it is lifted upright. 
         [0035]    The advantages of the present invention are made possible by the automation of the most dangerous elements of the drilling process. The drill pipe section connection process is technically difficult and may be dangerous to laborers who must handle the drill pipe sections as they kelly connects to them. Manually connecting the spinning drill pipe sections typically has been inefficient due to the necessity on human interaction and the concerns for human safety. With the present invention, the only necessary human interaction is with the controls of the mechanical elements. The connection of the top head and kelly, the kelly and the drill pipe, and the drill pipe and drill string are all done using the rotation of the top head as controlled remotely. Thus no human laborer must be near or in contact with the drill pipe as the drilling process is being engaged. 
         [0036]    It is to be understood that while certain aspects of the disclosed subject matter have been shown and described, the disclosed subject matter is not limited thereto and encompasses various other embodiments and aspects. The above-mentioned steps and components are not meant to limit the use or organization of the present invention. The steps for performing the method may be performed in any logical method and in any logical order.