Abstract:
This invention provides a self-contained mobile repair unit having a universal set of hydraulic and pneumatic tooling for servicing well equipment such as an inner pipe string, a sucker rod, or a pump. One or more transducers sense and collect data indicative of one or more parameters measured by the mobile repair unit, such as hook load, engine RPM, or tongue torque. The data is collected and saved in a non-volatile memory device, which is then physically transferred from the mobile repair unit to a central office location, where the data can be compiled, analyzed, and/or posted on a network such as the Internet.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    After an oil rig drills a well and installs a well casing, the rig is dismantled and removed from the site. From that point on, a mobile repair unit is typically used to service the well. Servicing includes installing and/or removing inner tubing strings, sucker rods, and pumps, and also requires various other monitoring functions such as detecting dangerous hydrogen sulfide gas. Such work requires a myriad of tools which are provided by the mobile repair unit, and these tools in turn provide a myriad of measured parameters such as torque turn, engine RPM, hook load, hydrogen sulfide concentration, etc. It is important to understand and interpret these measured parameters, as they can be important to assessing the quality, reliability, and safety of the work being accomplished at the mobile repair unit.  
           [0002]    The prior art discloses various ways in which these measured parameters can become known to mobile repair unit operators and/or their supervisors. For example, in U.S. Pat. No. 6,079,490, which is hereby incorporated by reference, the mobile repair units are fitted with modems for wirelessly sending the measured parameter data to a centralized data analysis location. While the use of a modem can be useful, it suffers from shortcomings that can hamper its usefulness in the context of a mobile repair unit. For example, wireless or modem transmission techniques are relatively expensive to implement and may be subject to lost or corrupted data during transmission.  
         SUMMARY OF THE INVENTION  
         [0003]    This invention provides a self-contained mobile repair unit having a universal set of hydraulic and pneumatic tooling for servicing well equipment such as an inner pipe string, a sucker rod, or a pump. One or more transducers sense and collect data indicative of one or more parameters measured by the mobile repair unit, such as hook load, engine RPM, or tongue torque. The data is collected and saved in a non-volatile memory device, which is then physically transferred from the mobile repair unit to a central office location, where the data can be compiled, analyzed, and/or posted on a network such as the Internet. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0004]    [0004]FIG. 1 is a side view of a mobile repair unit with its derrick extended.  
         [0005]    [0005]FIG. 2 is a schematic view of a pneumatic slip in a locked position.  
         [0006]    [0006]FIG. 3 is a schematic view of a pneumatic slip in an open position.  
         [0007]    [0007]FIG. 4 is a schematic illustration of a set of hydraulic tongs.  
         [0008]    [0008]FIG. 5 is a side view of a mobile repair unit with its derrick retracted.  
         [0009]    [0009]FIG. 6 illustrates the raising and lowering of an inner tubing string.  
         [0010]    [0010]FIG. 7 describes one embodiment of the design of a data acquisition monitor as described herein. 
     
    
     DESCRIPTION OF THE INVENTION  
       [0011]    This disclosure first details some of the basic tools present on a mobile repair unit and manner in which various measurements are made by these tools. Thereafter, the disclosure discusses the ways in which these measurements are stored and processed in accordance with embodiments of the invention.  
         [0012]    Referring to FIG. 1, a retractable, self-contained mobile repair unit  20  is shown to include a truck frame  22  supported on wheels  24 , an engine  26 , a hydraulic pump  28 , an air compressor  30 , a first transmission  32 , a second transmission  34 , a variable speed hoist  36 , a block  38 , an extendible derrick  40 , a first hydraulic cylinder  42 , a second hydraulic, cylinder  44 , a first transducer  46 , a monitor  48 , and retractable feet  50 . Monitor  48 , of special importance to the disclosed invention, receives amongst other things various parameters measured during the mobile repair unit&#39;s operation.  
         [0013]    Engine  26  selectively couples to wheels  24  and hoist  36  by way of transmissions  34  and  32 , respectively. Engine  26  also drives hydraulic pump  28  via line  29  and air compressor  30  via line  31 . Compressor  30  powers a pneumatic slip  84  (FIGS. 2 and 3), and pump  28  powers a set of hydraulic tongs  66  (FIG. 4). Pump  28  also powers cylinders  42  and  44  that respectively extend and pivot derrick  40  to selectively place derrick  40  in a working position (FIG. 1) and in a retracted position (FIG. 5). In the working position, derrick  40  is pointed upward, but its longitudinal centerline  54  is angularly offset from vertical as indicated by angle  56 . This angular offset  56  provides block  38  access to a well bore  58  without interference from the derrick framework and allows for rapid installation and removal of inner pipe segments (i.e., inner pipe strings  62 ) and sucker rods (FIG. 6).  
         [0014]    Individual pipe segments (of string  62 ) and sucker rods  64  are screwed together using hydraulic tongs  66  (FIG. 4). Hydraulic tongs are known in the art, and refer to any hydraulic tool that can screw together two pipes or sucker rods, such as those provided by B.J. Hughes company of Houston, Tex. In operation, pump  28  drives a hydraulic motor  68  in either forward or reverse directions by way of valve  70 . Motor  68  drives pinions  72  that turn a wrench element  74  relative to clamp  76 . Wrench element  74  and clamp  76  engage flats  81  on mating couplings  78  of a sucker rod or inner pipe string. However, rotational jaws or grippers that hydraulically clamp on to a round pipe (i.e., with no flats) can also be used in place of the disclosed wrench element  74 . The rotational direction of motor  68  determines whether the couplings  78  are assembled or disassembled.  
         [0015]    The transducer  80  of FIG. 4 detects by feedback the amount of torque that is used to assemble or disassemble the string  62  or sucker rods  64 , and provides an analog signal  82  (e.g., from 0-5 Volts DC) indicative of that torque value. This signal  82  is provided to monitor  48  and is stored in a manner to be described shortly.  
         [0016]    Referring to FIGS. 2 and 3, when installing inner pipe string segments  62 , pneumatic slip  84  is used to hold the pipe string  62  while the next segment  62 ′ is screwed on using tongs  66  as just described. Compressor  30  provides pressurized air through valve  86  to rapidly clamp and release slip  84 , as shown in FIGS. 2 and 3 respectively. A tank  88  helps maintain constant air pressure. Pressure switch  90 , a type of transducer, provides monitor  48  with a signal that indirectly indicates that repair unit  20  is in operation.  
         [0017]    Referring back to FIG. 1, weight applied to block  38  is sensed by way of a hydraulic pad  92  that supports the weight of derrick  40 . Hydraulic pad  92  is basically a piston within a cylinder such as those provided M. D. Totco company of Cedar Park, Tex., but can alternatively constitute a diaphragm. Hydraulic pressure in pad  92  increases with increasing weight on block  38 , and this pressure can accordingly be monitored to assess the weight of the block. Thus, pad  92  constitutes another type of transducer, and it too transmits a signal (not shown) to the monitor  48 .  
         [0018]    In short, and as is well known, the mobile repair unit contains numerous tools for performing various repair tasks, and most of these tools contain some sort of transducer for providing an indication of the work being performed. (As used herein, “transducer” should be understood as any sort of detector, sensor, or measuring device for providing a signal indicative of the work being performed by a particular tool). Using such transducers, important parameters can be measured or monitored, such as hook load, tong torque, engine RPM, hydrogen sulfide concentration.  
         [0019]    As noted, of the signals provide by the various transducers associates with the tools are sent to data acquisition monitor  48 . The primary objective of monitor  48  is to gather well maintenance data and save it so that it can be transferred and subsequently monitored at a site other than the location of the mobile repair unit, such as a central office site. Monitor  48  is generally installed in an openly accessible location on the mobile repair unit. For example, on a mobile repair unit, monitor  48  is installed somewhere outside the cab for easy access by human operators who may walk up to the mobile repair unit to interface with the system and collect data. In addition to storing the measured data from the tools, the monitor  48  may also include a screen display for displaying the data.  
         [0020]    In one embodiment, monitor  48  contains specialized circuits that are programmed to process the measured signals and store that data, either in raw or processed form, on a removable storage media containing nonvolatile semiconductor memory chips. A human operator physically interfaces with the system on site and removes the storage media from its plug in port on the monitor  48  and then physically transports the storage media from the mobile repair unit to a predetermined, central location, such as a central office site, for processing and analysis.  
         [0021]    In a preferred embodiment, the removable storage media constitutes a memory stick, as will be disclosed in further detail herein. Alternatively, the storage media may constitute another device containing nonvolatile memory chips, such as a hand-held computing device, for example, a Palm Pilot™, a Pocket PC, or a laptop computer. The hand-held computing device may be connected to monitor  48  via a wire connection using an available Ethernet port or an RS-232 port on the monitor  48 . Alternatively, the hand-held computing device can connect with monitor  48  using radio frequency (RF), infrared, or some other type of wireless means for the transferring the data to the hand-held computing device. As with the memory stick, the hand-held computing device can be physically transported from the mobile repair unit in the field to the central office site for processing and analysis.  
         [0022]    Once the processed data has been physically transported to the central location, it will be coupled to a computing station having a port similar to the port on the monitor for reading the data out of the storage media. In a preferred embodiment, the computing station will comprise or include computers or web servers capable of storing and if necessary processing the data into a format more readily useful to those at the central location who are responsible for monitoring the operation of the various mobile repair units deployed in the field. In a preferred embodiment, the computing station is connected to web servers so that oil well owners or others can access the mobile repair unit operation data using standard web browsers from any computer in the world via the Internet.  
         [0023]    [0023]FIG. 7 illustrates one embodiment of monitor  48 . Monitor  48  consists of sensor and interface module  210 , data acquisition module  220 , communication module  230 , user console  240 , and data storage module  250 . Generally, sensor and interface module  210  receives analog and digital signals from various transducers present on the mobile repair unit. For example, the hook load, tong torque, pressure, and temperature transducers might provide analog data to module  210 , while the engine RPM, block position, rotary RPM, and pump strokes transducers might provide digital data. In any event, sensor and interface module  210  is equipped to handle one or more analog input signals  212  and one or more digital input signals  214 . Module  210  is also capable of producing one or more analog output signals  216  and one or more digital output signals  218 . One skilled in the art will recognize that module  210  includes other electrical circuitry, such as amplifiers, multiplexers, and analog-digital converters, which are used to condition the input signals and if necessary to convert them to digital signals to facilitate further processing.  
         [0024]    Sensor and interface module  210  sends the digitized signals to data acquisition module  220 . Applications programs in Data Acquisition Module  220  process the signals and send processed data to Communication Module  230 . Data Acquisition Module  220  comprises CPU  222 , firmware  224 , clock  226  and memory  228 . Firmware  224  contains application programs that are designed to process the input signals received from sensor and interface module  210 . Clock  226  (like clock  236  present in the communication module  230 ) is preferably a real-time clock with battery back up and allows the data to be time stamped. Memory  228  is preferably a non-volatile one-megabyte flash ROM storage device, but can be any type of suitable memory device. Memory  228  is used to store calibration parameters and other user parameters. The address space of memory  228  is distinct and separate from the memory address space in CPU  222  and CPU  232 . The application programs in firmware  224  are executed in CPU  222  to process the mobile repair unit sensor measurement signals received from sensor and interface module  210 . For example, the CPU  222  might process the hydrogen sulfide transducer data to determine the concentration of hydrogen sulfide, or process the hook load and tong torque data to provide a measurement indicative of the completeness of the connection of two sucker rods.  
         [0025]    The processed data results are then transferred from the data acquisition module  220  to the communication module  230  to facilitate storage of the data and communication to the operators. Bus  229  is preferably an 8-wire parallel data bus, and preferably connects to an 8-bit parallel slave port on CPU  232  in module  230 . Firmware  234  contains application programs executable by the CPU  232  that are designed to: enable presentation of the processed data results (graphical and text) on a user console  240 ; enable storage of the processed data results in data storage module  250 ; and/or enable communication with a hand-held computing device such as those disclosed earlier and in the manners disclosed earlier. As noted earlier, user console  240  is integrated into monitor  48  via a direct-wired connection  242  through the Ethernet port in interfaces  238  of communication module  230 . A human operator preferably interacts with monitor  48  via user console&#39;s  240  touch-screen interface or keyboard, which allows the operator to run application programs in module  230  and to view graphical or textual representations of the processed data results. The operator may also use the interface to enter data into monitor  48  (such as job ticket information) or to manipulate calibration parameters stored in memory  228  of module  220 .  
         [0026]    Communication module  230  also stores the processed data results in data storage module  250 . In one embodiment, data storage module  250  consists of a fixed memory device  252  and the removable storage media device  254  alluded to earlier (e.g., the memory stick). On one embodiment, fixed memory device  252  comprises a flash ROM memory device or a magnetic disk drive. The removable storage media device  254  can comprise any number of portable non-volatile means for storing data, such as a floppy disc, a CD (compact disk), or a magnetic tape, but preferably constitutes a memory stick as will be disclosed in further detail herein. In any event, both memory devices interface with communication module  230  by any suitable means, such as by direct wire connections via separate 2-wire serial data buses  256  and  258  respectively. When module  230  receives the processed data from module  220 , one complete copy of the data results is stored in the fixed memory device  252  and a separate but identical complete copy of the data results is stored in the removable storage media device  254 . When a human operator uses console  240  to view processed data results, the application programs in firmware  234  of module  230  access the data stored in fixed flash ROM  252 .  
         [0027]    As previously explained, a copy of the processed data results that are stored in the fixed memory device  252  must be physically transported to the central office site. To accomplish this result, the operator has two options: the removable storage media option or the hand-held computing device option.  
         [0028]    Pursuant to the first option, the removable storage media device  254  is accessible to an operator from the outside of monitor  48 . Preferably, removable storage device  254  comprises a small, weatherproof cylinder containing a non-volatile memory chip (such as a Flash EEPROM) or memory module containing numerous such chips. The cylinder of device  254  is preferably filled with a suitable epoxy to stabilize the chip(s) and to protect them from moisture and mechanical shock. Pins connected to the chip(s) project from the epoxy along one end of the device and are insertable into the port on the monitor  48 . Care should be taken when choosing an epoxy to ensure that the chips will not overheat when they are operating. A human operator manually removes the removable storage media device  254  by physically removing the storage media from the data storage module  250  of the monitor  48  after it has been written with data. The operator then physically transports the removable storage media device  254  to the central office site. The operator then transfers the data to computers or web servers at the central office site by placing the removable storage media  254  into a memory reader that is connected to the web servers (e.g., via a local area network or a wide area network).  
         [0029]    Pursuant to the second option for transporting the data, the operator can connect a hand-held computing device  260  such as those disclosed herein to a port on monitor  48 . As mentioned earlier and as FIG. 7 contemplates, this can be accomplished via a physical wired connection using an available Ethernet port or RS 232 port, or can be accomplished via a wireless connection such as a RF or infrared connection. Computer application programs residing in the hand-held device  260  and firmware  234  work together to transfer a copy of the processed data results from fixed memory device  252  to the memory storage space of the hand-held computing device  260 . Once a copy of the processed data results has been stored in the hand-held device  260 , the operator then disconnects the hand-held device  260  from the port (if any) on the monitor  48  and physically transports the hand-held device from the remote mobile repair unit in the field to the central office site. Once the hand-held device  260  has been physically transported to the central office site, the operator transfers the data to web servers by connecting the hand-held device  260  to a computer at the central office site which is itself connected to central office site web servers (e.g. via a local area network or a wide area network).  
         [0030]    Once the processed data is transferred to web servers using either one of the two foregoing options, oil well owners and customers may access the processed operations data using standard web browsers from any computer in the world via the Internet or other more limited network, such as a intranet. Preferably, this is accomplished using secure UNIX-based web servers that require customers to enter a username and password at a login prompt before they are granted access to the processed data results. In this manner, mobile repair unit operations data may remotely assessed.  
         [0031]    Although the invention is described with respect to a preferred embodiment, modifications thereto will be apparent to those skilled in the art. Therefore, the scope of the invention is to be determined by reference to the claims that follow.