You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention generally pertains to service vehicles used in performing work at a well site, and more specifically to a method of monitoring the operations of multiple service vehicles. 
     2. Description of Related Art 
     After a well is set up and operating to draw petroleum, water or other fluid up from within the ground, various replacement parts and services are periodically provided to maintain the well. Such parts and services may include replacing worn parts such as a pump, sucker rods, inner tubing, and packer glands; pumping chemical treatments or hot oil down into the well bore; and pumping cement into the well bore to partially close off a portion of the well (or to shut it down entirely). Since wells are often miles apart from each other, the maintenance or service operations are usually performed by a mobile unit or service vehicle having special onboard servicing equipment suited to perform the work. Some examples of service vehicles include a chemical tank truck or trailer, a cement truck or trailer, a hot-oiler tank truck or trailer, and a portable work-over service rig having a hoist to remove and install well components (e.g., sucker rods, tubing, etc.). 
     Service vehicles are often owned by independent contractors that well companies (e.g., well owner or operator) hire to service the wells. For a single well servicing project, a well company may hire several different contractors, each having their own special equipment and areas of expertise. Each contractor may perform several different service operations. For example, one contractor with a work-over rig may replace tubing, sucker rods, and perforate casing. Another contractor, with a tank truck, may stimulate the well and provide a hot oil treatment Yet, another contractor may deliver parts or provide rental equipment. With several independent contractors each doing several different jobs, the oil company may find it difficult to keep track of everything that is going on at the well site. 
     Consequently, some service operations may be done improperly or may be overlooked entirely. The oil company may receive invoices for work that was never performed. If an accident or some other notable incident occurs at the well site, it may be difficult to determine the cause or who was involved. If the various contractors each prepare their own service report, the well company may still need to sort through all the reports to determine what was done, who did it, and when it was done. Sorting through the various reports can be especially difficult and time consuming if each report follows a different format, which may be unique to each individual contractor. 
     SUMMARY OF THE INVENTION 
     To avoid the problems and limitations of current methods of monitoring operations at a well site, it is an object of the invention is to collect data directly at the well site, wherein the data identifies what was done and who did it. 
     A second object is to allow a contractor to specify what service operation is about to be performed by providing the contractor with a menu of service operations from which to choose. 
     A third object is to generate directly at the well site a cohesive report that identifies which service operation is supposedly being performed, a transducer reading that substantiates the service operation was actually being carried out, and which contractor was involved in doing the work. 
     A fourth object is to generate directly at the well site a cohesive report that identifies several service operations supposedly being performed, several transducer readings that substantiate that the service operations were actually being carried out, and which contractor was involved in doing the work. 
     A fifth object is to generate directly at the well site a cohesive report that identifies several service operations supposedly being performed, several transducer readings that substantiate that the service operations were actually being carried out, and a list of several independent contractors that were involved in doing the work. 
     A sixth object is to generate directly at the well site a cohesive report that identifies facts about an accident or an environmental incident that occurred at the well site. 
     A sixth object is to generate directly at the well site a cohesive report that identifies which service operation is supposedly being performed, a transducer reading that substantiates the service operation was actually being carried out, which contractor was involved in doing the work, and a time stamp that identifies when the service operation was being performed. 
     A seventh object is to generate directly at the well site a cohesive report that identifies which service operation is supposedly being performed, a transducer reading that substantiates the service operation was actually being carried out, and which employee was involved in doing the work. 
     An eighth object is to generate directly at the well site a cohesive report that identifies which service operation is supposedly being performed, a transducer reading that substantiates the service operation was actually being carried out, which contractor was involved in doing the work, and at which well site the work occurred. 
     A ninth object is to generates a report that summarizes the work performed by one or more contractors using one or more special service vehicles designed specifically to assist in performing certain service operations at a well site. 
     A tenth object is to further use such a service vehicle to transport a computer to the well site, wherein the computer is used to create a report that identifies the activities at the well site. 
     An eleventh object is to provide a wireless communication link between a first computer at a home base location and a second computer at a remote well site, so that report information collected on the second computer can be almost immediately communicated to the first computer, thereby providing a well company with timely access to the report. 
     A twelfth object is to validate that a service operation is actually being performed by sensing pressure or rotational speed of a motor associated with the service operation. 
     These and other objects of the invention are provided by a method of monitoring operations at a well site that involves collecting data directly at the well site, wherein the data identifies which service operation is supposedly being performed, a transducer reading that substantiates that the service operation was actually being carried out with the assistance of a service vehicle, and which contractor was involved in doing the work. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic diagram illustrating a method of monitoring operations at a well site according to a currently preferred embodiment of the invention. 
     FIG. 2 schematically illustrates the basic elements of a report created by the method of FIG. 1, wherein the report is displayed on a monitor of a computer. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1 and 2 schematically illustrate a method  28  of monitoring activities pertaining to a well  30  at a well site  32 , and summarizing the results in a cohesive report  34 . Report  34  covers a variety of service operations performed by one or more contractors using one or more service vehicles. 
     Well  30  is schematically illustrated to encompass any apparatus for drawing a fluid (e.g., oil, gas, water, etc.) from the ground. In some embodiments of the invention, well  30  includes a string of outer piping known as casing  36 . When perforated, casing  36  provides a conduit that conveys fluid from within the ground to the inlet of a submerged reciprocating pump  38 . An inner string of pipe, known as tubing  40 , provides a discharge conduit that conveys the fluid from the outlet of pump  38  to the surface. A powered pivoting beam (not shown) moves a string of sucker rods  42  up and down, which in turn moves the pump&#39;s piston up and down to pump the fluid. 
     To service or maintain well  30 , an oil company  44  (e.g., well owner, operator, or representative thereof) hires one or more contractors  46  and  48  to provide the necessary goods and services. Examples of common parts that contractors  46  or  48  may replace at well site  32  include, but are not limited to, casing  36 ; tubing  40 ; sucker rods  42 ; pump  38  or its components, such as seals and valves; casing couplings  50 ; tubing couplings  52 ; sucker rod couplings  54 ; packer glands; and various parts associated with the pivoting beam, such as its drive motor. Examples of various consumable and non-consumable fluids  56  that may be added to the well bore include, but are not limited to hot oil, acid, or cement. Examples of common services operations that contractors  46  or  48  may perform at well site  32  include, but are not limited to, delivering parts; manipulating sucker rods (e.g., installing, torquing, or replacing rods  42 , as indicated by arrow  58 ); manipulating tubing (e.g., installing, torquing, or replacing tubing  40 , as indicated by arrow  60 ); perforating casing  36 , as indicated by a perforating gun  62  suspended from a cable or wireline  64 ; down hole logging, as indicated by a transducer  7  also suspended from a wireline; pumping fluid  56  (e.g., cement, acid, steam, hot oil, etc.) into well  30 , as indicated by pump  68  and arrow  70 ; welding; fracture treatments, testing; drilling; providing rental equipment; and various other work that is familiar to those skilled in the art. The list of possible goods (e.g., consumable and non-consumable parts and fluids) and services could be considered endless, as new components and services are continually being developed. 
     To provide the various goods and services, contractors  46  and  48  preferably use a service vehicle. The term, “service vehicle” refers to any vehicle used to facilitate delivering parts and/or performing one or more service operations on well  30 . Examples of a service vehicle include, but are not limited to, mobile work-over unit  72  and a tanker  74 . Work-over unit  72  includes a variety of equipment including, but not limited to, tongs  76  (e.g., rod tongs or tubing tongs), and a wireline winch and/or a hoist  78 . Work-over unit  72  is particularly suited for removing and installing well components, such as sucker rods, tubing, etc.; lowering instruments into the well bore via a cable or wireline; and may even be used in actually drilling the well bore itself Tanker  74  is schematically illustrated to encompass all other types of service vehicles including, but not limited to, pumping vehicles, such as a chemical tank truck or trailer, a cement truck or trailer, and a hot-oiler tank truck or trailer. 
     One of the service vehicles, such as vehicle  72 , also transports a computer  80  to well site  32 , as depicted by arrow  82 . The term, “computer” used herein and below refers to any device for storing and/or possessing digital information. Examples of a computer include, but are not limited to, personal computers, PC, desktop computer, laptop, notebook, PLC (programmable logic controller), data logger, etc. Computer  80  with common software (e.g., Microsoft Word, Excel, Access; Visual Basic; C++; etc.) allows contractor  46  to begin creating report  34  right at the well site. 
     For example, contractor  46  may begin by entering into computer  80  a well site identifier  84 , such as an alphanumeric name, number, address or code that identifies (e.g., by name or location) well  30  or well site  32 . The step of entering or identifying well site identifier  84  is schematically depicted by arrow  86 , and can be accomplished manually by using a keyboard  88  or can be entered in some other conventional manner, such as scanning a bar code label, sensing a radio frequency identification device, or selecting from a menu of well site identifiers displayed on computer  80 . 
     In a similar manner, contractor  46  may enter a contractor identifier  90 , which identifies contractor  46  by name, number, or some other code that distinguishes one contractor from another. If desired, contractor identifier  90  may comprise an employee identifier  92 , such as a name, number, or some other code that distinguishes one employee from another. 
     Contractor  46  may also enter or identify a service operation  94  (FIG. 2) that is about to be performed with the assistance of service vehicle  72 . Identifying service operation  94  is preferably done by selecting from a menu of several service operations  96 . For illustration, contractor  46  identifies or selects “Pulling Rods” (i.e., removing sucker rods) from menu  96 . Menu  96  may include other service operations, such as Installing Rods, Pulling Tubing, Installing Tubing, Pumping, Testing, and Delivery (e.g., delivery of parts or rental equipment). Other examples of service operations that are well known to those skilled in the art and could be listed in menu  96  include, but are not limited to, perforating, stimulating, swabbing, drilling, and bailing. Upon selecting a particular service operation, computer  80  begins collecting data pertaining to that operation as the operation is being performed. 
     In the case of pulling rods, computer  80  may record several transducer readings, one of which may be the change in load carried by hoist  78 . To do this, a transducer  1  senses the weight which hoist  76  applies to vehicle  72 . In response to the applied weight or load, transducer  1  generates an electrical signal  11 . A conventional A/D converter associated with or incorporated within computer  80  converts electrical signal  11  (or any other electrical signal) to a digital value  21 , which is then stored on computer  80 . Computer  80  then creates and/or displays report  34  which, in this simplified example, comprises contractor identifier  90 , service operation identifier  94 , and digital value  21 . 
     Computer  80  may collect and record numerous other transducer readings that help substantiate various service operations are actually being performed. For example, when pumping fluid  56  (e.g., hot oil, chemical, acid, gas, water, steam, cement, etc.) a transducer  2  can monitor things such as the fluid&#39;s volume or mass flow rate, pressure, temperature, acidity, or concentration. In some service operations, such as the removal and replacement of sucker rods  42 , packer glands, tubing  40 , etc., a transducer  3  (e.g., a proximity switch) could determine whether parts are being removed or installed. When replacing sucker rods  42  or other well components, transducer  1  could monitor the load carried by hoist  78  while another transducer  4  could monitor a hoist engine speed. Together, transducers  1  and  4  could monitor the power required to pull rods  42  or tubing  40  from the well bore. For tongs  76 , which are powered by a hydraulic system on vehicle  72 , a transducer  5  can be used to monitor or control the tong&#39;s hydraulic pressure or torque. Another transducer  6  can be used to monitor or control the tong&#39;s rotational speed. Transducer  7  can indicate the density of the ground surrounding casing  36  or can indicate the integrity or wall thickness of casing  36 . The term, “transducer” refers to any device that provides an electrical signal in response to sensing a condition or status of a service operation. Examples of a transducer include, but are not limited to, a pressure switch, a strain gage, a temperature sensor, a flow meter, a tachometer, a limit switch, a proximity switch, etc. For the embodiment of FIG. 1, transducers  1 ,  2 ,  3 ,  4 ,  5 ,  6  and  7  respectively provide electrical signals  11 ,  12 ,  13 ,  14 ,  15 ,  16  and  17 , which in turn are converted to digital values such as signals  11  and  12  being converted to digital values  21  and  22  respectively. Of the digital values generated from transducers  1 - 7 , any or all may be recorded as part of report  34 . Report  34  may include several samplings of several transducers, several samplings of just one transducer, or just one reading of just one transducer. 
     Other information may also be included in report  34 . For example, report  34  may include one or more time stamps  98  that indicate the time of day that one or more particular service operations, such as pulling rods, were being performed. Time stamp  98  can be provided by an internal clock of computer  80  and can appear in various formats, including, but not limited to, a chart, graph, single entry, etc. Report  34  may also include a journal entry  101  (e.g., in a text format) that identifies or describes an accident or some other adverse incident (injury, oil spill, damage to equipment, etc.) that may have occurred at well site  32 . 
     Report  34  may store or document much more information and may span several days. For example, later in the day or on another day, contactor  46  may perform another service operation, such as “Pulling Tubing.” Computer  80  would then collect another set of data pertaining to the removal of tubing. 
     In some cases, a second contractor  48  operating vehicle  74  may perform yet another service operation. In this case, contractor  48  would enter (indicated by arrow her contractor identifier  102 , which may identify the contractor&#39;s name or identify an employee of the contractor, as indicated by employee identifier  104 . If contractor  48  selects “Pumping” as a service operation, computer  80  may collect and store data pertaining to a pumping operation. For instance, report  34  may include one or more time stamps  100  and one or more values  22  that correspond to readings from transducer  12 . 
     It should be noted that the format of report  34 , as shown in FIG. 2, is for illustrative purposes to clarify the overall idea of the invention. The actual format of report  34  could vary widely and still remain well within the scope of the invention. For example, in some embodiments of the invention, report  34  is displayed on computer  80  through several different screens that a user can view by scrolling or paging up or down through the various screens (wherein a screen is a one-page display on a computer monitor). If desired, well site identifier  84 , contractor identifiers  90  and  102 , employee identifiers  92  and  104 , digital values  21  and  22 , time stamps  98  and  100 , one or more service operation identifiers of menu  96 , and journal entry  101  can each appear on a different screen. Likewise, a printed version of report  34  may also be on one or more pages. 
     From computer  80 , report  34  (i.e., in its entirety or portions of it) can be communicated by way of a wireless communication link  106  to another computer  108  at a remote location  110 , such as a home base from which company  44  operates. The term, “remote location” refers to a location that is beyond the immediate property or land on which well  30  is contained or one mile away from well  30 , whichever is greater. The term “wireless communication link” refers to data being transmitted over a certain distance, wherein over that certain distance the data is transmitted through a medium of air and/or space rather than wires. Wireless communication link  106  is schematically illustrated to represent a wide variety of systems that are well known to those skilled in the art of wireless communication. For example, with a modem  112  and an antenna  114  associated with computer  108 , and another modem  116  and an antenna  118  for computer  80 , data of report  34  can be exchanged between computers  80  and  108  using the Internet and any one of a variety of common formats including, but not limited to, HTML, e-mail, etc. Thus, company  44  is provided with access to report  34  as the report is being created or soon after one or all of the service operations are complete. 
     It should be noted that method  28  is particularly useful when contractors  46  and  48  are independent contractors, and vehicles  72  and  74  each assist in performing a different service operation. The term, “independent contractors” refers to contractors that are not employees of company  44 , wherein each contractor has their own employees. 
     Although the invention is described with reference to a preferred embodiment, it should be appreciated by those skilled in the art that various modifications are well within the scope of the invention. Therefore, the scope of the invention is to be determined by reference to the claims that follow.

Summary:
A method of monitoring service operations performed on a well involves creating, directly at the well site, a cohesive report of what work was done to the well and which of several contractors did the work. The report includes supporting data generated by one or more transducers. The transducers sense various conditions of a process or service operation, which is being performed by a contractor with the assistance of a special service vehicle. The report is computer generated and can be conveyed from a remote well site to a home base location using two computers communicating across a wireless communication link. The method is particularly useful when the work at the well involves several independent contractors using different service vehicles to perform different service operations.