Abstract:
A mobile apparatus supported on a trailer measures, analyzes, and monitors drilling fluids on an oil &amp; gas site. The system includes a modular automated test unit having instruments for measuring and analyzing physical and chemical drilling fluid parameters including but not limited to viscosity, density, pH, electrical stability, fluid loss, rheological parameters, retort analysis, titrations for mF, pF, POM, chlorides, hardness, calcium, and chromatographic analysis. 
     The system further includes a manifold system situated between a drilling mud reservoir and a network of conduits, for distributing drilling fluid to be analyzed by the instruments. Also included is a system hub, coupled as an interface between a program-operated data processing and communication system and the manifold and system instruments, for communicating control and data information and routing storage in a database of the data outputs of the instruments.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority to U. S. Patent Application Ser. No. 62/356,042 entitled APPARATUS AND METHODS FOR AUTOMATED ON SITE COMPOSITION, ADMINISTRATION, AND ANALYSIS OF DRILLING FLUIDS and filed Jun. 29, 2016 by the same inventor. 
     
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
       [0002]    The present invention generally relates to the management of drilling fluid uses at an oil &amp; gas drilling site, and more particularly to a system, apparatus, and methods for automated analysis of drilling fluids at a drilling site. 
       2. Description of the Invention and Background of the Prior Art 
       [0003]    The process of drilling oil and gas wells typically includes the use of various compositions of drilling fluids to facilitate the process. Some of the purposes of drilling fluids or muds include but are not limited to remove cuttings of rock and other debris from the formation, to operate downhole tools using the power of hydraulic fluid, to control drilling parameters and cool and lubricate the drill bit, to control erosion in the borehole, to stabilize the formation, etc. Other purposes include controlling formation pressures, and to control substances embodied in the fluids encountered in the formation. Various chemicals, in liquid, solid, or gas form may be combined with water (aqueous-based) or mineral oil (non-aqueous-based) to meet specific needs of the drilling site. 
         [0004]    Drilling fluids are designed to embody a variety of properties depending on the particular needs of the drilling operation. These properties include weight and density, viscosity, chemical composition, pH, and hardness. In addition, rheological measurements are often needed to measure the flow characteristics of the drilling mud such as shear stress arising from the flow velocity and viscosity of the fluid within the well. Often it is necessary to know whether the fluid is liquid or a mixture of liquid and solids, or of liquid and gas, which are known respectively in the art as continuous, dis-continuous, and gas phases of the drilling fluid. Thus in general it is necessary to continually analyze and monitor the composition and parameters of the drilling fluids to ensure that they are functioning as designed. 
         [0005]    Facilities for measuring drilling fluids vary widely, and traditional services, which typically must be staffed by a mud technician or engineer, very often produce results of limited comprehensiveness, accuracy, or use. There are many and varied reasons that drilling fluid measurement and monitoring systems presently available fail to perform to optimum levels. Errors in calibration of the equipment and or transcription of results are commonplace. Safety is sometimes compromised by inattentiveness of operators or other personnel tasked with performing the required tests. Wasteful use of additives and other products to the fluid impairs cost efficiency. Tests run by inexperienced or unqualified personnel can negate the utility of results. The availability of test data is often not very timely or is subject to the judgment of the service provider. 
         [0006]    What is needed is an accurate, reliable, comprehensive system for measuring and monitoring drilling fluids that operates automatically, requires minimal attention after set up, and produces regular and timely reports of drilling fluid performance to rig operators so that the uses of drilling fluids may be optimized. 
       SUMMARY OF THE INVENTION 
       [0007]    A mobile, automated drilling fluid analysis system that continuously performs analysis tests in sequence and periodically at timed intervals, and stores the data in a database, is provided, comprising a housing disposed on a mobile frame and configured for connections to electrical power, and a fluid conduit system from and to a drilling fluid reservoir; a computer system disposed within the housing and configured with non-volatile storage, a communications interface to a network, and a suite of program software for controlling operations of the analysis system to measure, analyze, store, communicate, and compose output displays, summaries, and reports thereof through graphical peripherals and remote connections to the system; an automated test unit enclosed within the housing and coupled through a manifold to the fluid conduits system, the automated test unit having a dual, motor-driven turntable including a first turntable for measuring physical parameters and a second turntable for measuring chemical parameters; and a metering mechanism for depositing drilling fluid samples pumped through the fluid conduits from the drilling fluid reservoir into test containers on the first or second turntables; wherein the automated test unit provides for receiving, sensing, and measuring multiple physical and chemical parameters of the drilling fluid samples in a prescribed, continuous sequence according to analysis routines of the program software and compiling the analyzed parameters for storage or display. 
         [0008]    In one aspect the modular automated test unit may be constructed as a self-contained unit configured for operating in several alternative modes depending on the particular combination of tests the ADFA system  10  is set up to perform. As noted previously, the system may be configured to operate unattended, continuously according to a predetermined sequence of tests. 
         [0009]    In another aspect, the operating program applications comprise program sequences for controlling individual electric actuators to regulate the flow of fluid to and from each instrument; receiving and storing raw data in the system database; compiling data outputs provided from the instruments; sending the compiled data from the system database via wireless link to one or more external terminals on request; and organizing the timing and sequence of measurement and analysis operations on samples of drilling fluid distributed from the manifold according to information about the type of drilling fluid. 
         [0010]    In another aspect, the plurality of instruments comprises an assembly of instruments for measuring and analyzing viscosity, density, pH, electrical stability, fluid loss, rheological parameters, retort analysis, titrations for mF, pF, POM, chlorides, hardness, calcium, and chromatographic analysis. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  illustrates a system block diagram of the present invention according to one embodiment; 
           [0012]      FIG. 2  illustrates a pictorial drawing of a mobile automated drilling fluid analysis system installed on a trailer chassis and including its operative components, according to the one embodiment of  FIG. 1   
           [0013]      FIG. 3  illustrates a block diagram depicting the data processing and communications system operatively connected to the automated drilling fluid analysis system of  FIGS. 1 and 2 ; 
           [0014]      FIG. 4  illustrates a system block diagram with components arranged in a sequence for analyzing drilling fluid according to the embodiment of  FIGS. 1, 2 and 3 ; 
           [0015]      FIG. 5A  illustrates a plan view of first and third portions of the modular automated test unit of  FIG. 4  configured for a first mode of operation according to one embodiment of the invention; 
           [0016]      FIG. 5B  illustrates a side elevation view of a second (intermediate) portion of the modular automated test unit of  FIG. 4  configured for a first mode of operation according to the embodiment of  FIG. 5A ; 
           [0017]      FIG. 6A  illustrates a plan vie of first and third of portions of the modular automated test unit of  FIG. 4  configured for a second mode of operation according to another embodiment of the invention; and 
           [0018]      FIG. 6B  illustrates a side elevation view of a second (intermediate) portion of the modular automated test unit of  FIG. 4  configured for the second mode of operation according to the embodiment of  FIG. 6A . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    In an advance in the state of the art the present invention provides a comprehensive computer controlled laboratory analysis system contained in a mobile housing or trailer. The system includes all of the computer processing and measurement analysis instrumentation needed to measure all properties of interest of various types of drilling fluids (aka, drilling mud) in use at active oil &amp; gas drilling sites. The system performs the measurements, receives, compiles, and stores the data, prepares reports, and responds to requests to upload the data to external terminals both to on-site and to remote office locations. The system fully automates the tasks of taking to samples of the drilling fluid pumped through the system, performs physical and chemical measurement and analysis on the samples continuously or according to a predetermined schedule, reports the data, and monitors the condition of drilling fluid at the site of the drilling operations. 
         [0020]    The principle benefits of the system include the ability to provide measurements and analysis of all necessary drilling fluid parameters, a substantially improved accuracy of the measurements, reducing or eliminating the need for an on-site technician or engineer to perform the tests and prepare reports of the analyses, reporting the data on a continuous or periodic basis, and the ability to upload results responsive to requests from external locations. All of these advantages together provide increased productivity of the drilling operations. 
         [0021]    For example, precision measurements of mud weight, viscosity, density, whether liquids or slurries, can be measured by mass flowmeters coupled to the system. Accurate rheological measurements may be made using viscometers that automatically heat the sample fluid for measurement instead of using a simple thermometer to determine when the specified temperature of the sample is reached. The automated system described herein can create complete, API standardized drilling fluid reports at user-specified intervals and transmit them to mud and drilling engineers, who may be remotely located, and to rig operating personnel in the dog house according to the rig owner or operator&#39;s requirements. Calibrations of the system instruments can be carried out automatically and periodically to ensure accuracy. When the system to be described herein is understood, persons skilled in the art will realize the versatility of the concept, that a variety of instrumentation may be incorporated into the system. 
         [0022]    The system is mobile and thus can be towed to the customer&#39;s site, connected to the mud reservoir, and set up and calibrated with minimal downtime or interruption of rig functions. The system replaces the traditional limited monitoring facilities requiring a staff member&#39;s presence with a self-contained machine that provides periodic and comprehensive reports essentially in real time. 
         [0023]    A key and novel part of the mobile, automated drilling fluid analysis system described herein is a modular automated test unit for computer-controlled testing of both solid and fluid constituents of drilling fluid in a single device or test unit. This device includes first and second rotatable test container platforms (aka “turntables”) that are driven by a common drive shaft coupled to an electric motor. The first platform is in an upper portion of the test unit and the second platform is in a lower portion of the test unit. This upper platform may be provided in two or more interchangeable versions, depending on the suite of tests that must be performed. In the illustrated examples, there are two types of platforms used in the upper portion of the test unit, type A configured for filtration and filter cake tests, and type B configured for solids and fluid percentage tests. 
         [0024]    The second rotating platform of the modular automated test unit structure, which may be termed a type C platform, is located in a lower portion of the test unit device. This platform tests the filtrate and determines density and constituent percentage measurements, whether the filtrate is water based mud (WBM) or oil-based mud (OBM). For example, it can test whether the oil based mud in use contains water, a condition that should be documented. The density is tested by subjecting the filtrate to two different “floats” that have weights that correspond to the densities of water based and oil based drilling fluids (“muds”). DI (deionized) water alone has a density of 8.334 pounds per gallon (ppg). Oil alone may have a density between 6.7 to 7.5 ppg. Thus, a 5.0 ppg float will float on water or oil. A 8.3 ppg float will not float on water alone but may float on a mixture of water and oil. The use of the floats in the filtrate tests will be described herein below. 
         [0025]    The platforms or turntables in the upper portion of the modular automated test unit are filled by an automated titration system (aka “automated loader”). The test tubes in the lower rotating platform are filled by a vacuum pump and condenser system that receives drilling fluid from the outlet of the upper platform. A first version of the first or upper platform (type A) may be used for filtering the drilling fluid, testing fluid loss and filter cake of a drilling fluid sample titrated into a cup. The first platform, when alternately configured with beakers (type B), may also be used for testing solids and fluid percentage of a sample titrated into a beaker. The platforms are circular and contain a plurality of positions for holding the cups or beakers so that they may be rotated from one indexed position to another to test a series of samples, for example at timed intervals. 
         [0026]    The second rotatable test platform (type C) in the lower portion of the automated test unit, also circular, has a similar number of positions for test tubes containing samples of the fluid transferred from the first platform through the vacuum pump and condenser system disposed within the automated test unit. The tests performed by the second test platform may be called “chemical” tests, in contrast with the tests performed by the first platform, which may be called “physical” tests. 
         [0027]    There are at least two possible configurations of the modular automated test unit. A first configuration is to house interchangeable upper test platforms (either type A and B) and a lower test platform (type C) in a single housing. In this case the modular automated test unit may be operable in two modes—mode I and mode II—as will be described. In a second configuration, two separate automated test units may be each housed in a separate housing, one dedicated to mode I and the other dedicated to mode II. The entire system may be configured in a variety of ways without departing from the concept of a fully automated drilling mud analysis system assembled from the components to be described herein. 
         [0028]    This modular automated test unit is an important part of the entire system that will be described herein, as shown in block diagram form in  FIG. 4 . The entire system is capable of performing a comprehensive series of tests on drilling fluid on a continuous schedule. The schedule may include repetition of certain tests. The sequence of tests described herein may, for example, include funnel viscosity and density tests, an electric stability meter, and an in line rheometer, followed by the automated test unit for testing fluid loss, filter cake, solids and fluid percentage, etc. For convenience and portability, the system is self-contained and housed in a trailer that may be towed from location to location, connected to a source of electrical power and a drilling mud pit or reservoir, and set up for unattended operation with a minimum of time and attention to calibration, etc. The system includes interface devices for communication with remote offices or other facilities. 
         [0029]    The entire system, including the modular automated test unit module, is programmed for computer control to perform at least the following kinds of operations, in addition to the operation of each of the instruments in the system: (1) controlling individual valve actuators via a system manifold and a system hub or interface to regulate the flow of fluid to and from each instrument through a system of conduits coupled to the manifold; (2) activating sensors and other measurement devices to take samples; (3) compiling data outputs provided from the instruments; (4) receiving and storing raw data in a database both on-site and at a remote office; (5) sending the compiled data from the database via wireless link to one or more external terminals on request; and (6) organizing the timing and sequence of measurement and analysis operations on samples of drilling fluid distributed from the manifold according to information about the type of drilling fluid. 
         [0030]    The following detailed description of an exemplary embodiment, is illustrated in the accompanying drawings to depict and explain the concepts and operation of the present invention. Reference numbers appearing on more than one figure refer to the same structural feature. 
         [0031]      FIG. 1  illustrates a system block diagram of the present invention according to one embodiment. The mobile, automated drilling fluid analysis system (“ADFA”)  10  is connected between a drilling fluid reservoir  12  on an oil or gas drilling site and an external network  20  for communicating with a remote office or terminal (not shown). The reservoir  12  contains drilling fluid or mud  14  deposited after use during drilling a well. The drilling mud  14  is retained for reuse. The ADFA  10  is used for analyzing samples drawn through conduit  16  to determine various physical and chemical properties of the drilling mud. Fluid is returned to the reservoir  12  after analysis through the conduit  18 . 
         [0032]      FIG. 2  illustrates a pictorial drawing of a mobile, automated drilling fluid analysis system  30  installed on a trailer chassis  28  and including its operative components, according to the one embodiment. The trailer  28  may include a trailer hitch frame assembly  38  for towing the trailer from place to place or maneuvering it into position at a site of use. A trailer body to enclose the equipment is not shown to more clearly depict its contents. The diagram illustrates the relationships of the individual components with one another. However, their actual physical locations may vary according to a particular embodiment. A fluid line  32  from the reservoir  12  supplies drilling fluid  14  via a pump  34  to a manifold system  42  that may be located within a cabinet  40  on the trailer  28 . The manifold system  42 , a ubiquitous device well understood in the art, is contained within the cabinet  40 . The manifold system  42 , which has an inlet coupled the fluid line  32  and a plurality of actuator-controlled outlets to individual instruments, functions as a kind of distribution hub between the active pits and the various instruments of the system. 
         [0033]    A fluid line  36  provides a return path from the automated drilling fluid analysis system  10 , located generally on the trailer  28 , to the reservoir  12 . The fluid may be circulated through the system by a main pump  34  and by auxiliary pumps (not shown) operated by actuators (not shown) controlled by the workstation  90  or by a server operating by remote control. 
         [0034]    The instruments, including the modular automated test unit, may generally be housed in cabinets within the trailer  28 . In the illustrated example, a first cabinet  50 , supplied fluid for analysis by conduit  96 , may contain a first automated test unit  52  (or first ATU  52 ), not shown but may be located inside cabinet  50 , for example. The first ATU  52 , configured for Mode I analysis, may preferably include an automatic titrator  54  for feeding fluid samples to first and second rotating turntables  56 ,  58  respectively. The Mode I analysis includes tests for filter cake using turntable  56  and tests for fluid loss using turntable  58  as will be described with  FIG. 5 . A second ATU  62 , perhaps contained in a second cabinet  60  in this example and supplied fluid for analysis by the conduit  96 , may be configured for Mode II analysis. In Mode II the ATU  62  may also preferably include an automatic titrator  54  for feeding fluid samples to first and second rotating turntables  66 ,  68  respectively. The Mode II analysis includes tests for the solid content of the drilling fluid using turntable  66  and tests for fluid percentages using turntable  68  as will be described with  FIG. 6 . 
         [0035]    The trailer  28  may be configured for including a variety of other drilling fluid analysis instruments. For example, a third cabinet  70  may be used for housing a chromatography unit  72  (not shown) and conduits and actuators for controlling the movement of drilling fluids inlet via conduit  98  to the instrument. Similarly, a fourth cabinet  80  may be used for housing viscometer rheometers (not shown) or other instruments supplied drilling fluid for testing by automatic titrators (not shown). These components not shown are similar in general function to the instruments to be described in detail that are depicted in  FIGS. 4, 5 and 6  herein. Return paths for drilling fluids following the analysis tests performed within the cabinets  50 ,  60 ,  70 , and  80  may be provided through the conduits  96  and  98 . A workstation  90  such as a desktop computer (not visible in  FIG. 1 ) for use by an operator, such as for set up, or attended operation, etc., may be installed in a separate cabinet on the trailer  30  or on a small table within the body of the trailer  28 . 
         [0036]      FIG. 3  illustrates a block diagram depicting the data processing and communications system operatively connected to the automated drilling fluid analysis system of  FIGS. 1 and 2 . The automated drilling fluid analysis (ADFA) system  10  and the computer system  100  provided for its programmed control form an integral system  102 , although the physical units may be located within different cabinets on the trailer  28 . For example, the ADFA  10  may be located in second cabinet  50  while the computer system  100  mat be located in the first cabinet  40  with the manifold system  42 . The particular choice is left up to determination by the manufacturer. In the drawing, a CPU  104 , includes at least a program memory  106 , and a communication interface  108  for connection with an external network  20 . The CPU  104  may also be connected to a display  110  and a database  112 . The program memory  106  may contain software programs for operating the pumps and valve actuators disposed for controlling the flow of fluids through the instrumentation within the trailer  28  and for communicating with a remote office via the network  20 . Communication with the external network  20  may include signals for operating control, revision of testing sequences, reporting results or alarm indications and the like. The database  112  provides storage for test results and for supplying test data upon request. The acquisition and control signals are communicated to the ADFA  10  via the control lines  114 . 
         [0037]      FIG. 4  illustrates a system block diagram with components arranged in a sequence for analyzing drilling fluid according to the embodiment of  FIGS. 1, 2 and 3 . The ADFA  10  may be adapted to include a variety of instrumentation for measuring and analyzing the constituents and properties of drilling fluids. The example shown in  FIG. 4  is illustrative but should not be construed as limiting to the particular instruments and components included in the diagram. The Modular automated drilling fluid test unit  130  (also identified as “automated test unit” elsewhere in this description) is a new and novel component, designed specifically for this application because of the lack of any other currently available system with its capabilities. The test unit  130  combines facilities not previously available in a self-contained unit for testing and monitoring both physical and chemical properties automatically and continuously according to a predetermined sequence and schedule. This capability provides substantial operating efficiencies that result from the automated control, lack of need for an attendant to operate the system, record the data, change the sequence, initialize the equipment before each round of tests, etc. The result is a significant advance in the state of the art, providing improved accuracy of test data as well as reducing the need for—and the expense of—on-site personnel to operate the system. 
         [0038]    The entry point of the exemplary system  10  begins at the inlet from the drilling fluid reservoir  12 . Fluid is pumped from the reservoir by main pump  34  through a conduit  140  and a “junk basket”  150  to remove material that is likely to clog the instrumentation or contaminate the measurements. Several conventional instruments such as a funnel viscosity and density device  152 , an electric stability meter  160 , and an in-line rheometer  162 , all of which are well known in the art may be included within the system  10 . A second pump  170  may be used between the outlet of the in-line rheometer and the automated titrator  132  of the modular automated drilling fluid (“ADF) test unit  130 . Each of these individual test components may be connected in a bypass loop if it necessary to temporarily bypass a selected test unit because of malfunction, the need for service, or to bypass attest that is not required. The bypass configuration around the electric stability meter, for example, is provided by a pump and bypass valve  154  that routes the test fluid via a conduit  156  to a second pump and bypass valve  158 . Both bypass valves  154 ,  158  may be computer controlled via actuators provided with each valve. The same scheme may be used to bypass other components of the system. 
         [0039]    The modular ADF test unit  130  will be described in two versions, a type A as shown in  FIG. 5  and a type B as shown in  FIG. 6 . Type A operates Mode I, designated by reference number  134 A. The Mode I ( 134 A) test unit includes tests for fluid loss and filter cake, to be described in  FIG. 5 . Type B operates Mode II, reference number  134 B. The Mode II ( 134 B) test unit includes tests for solids and percentage fluids, to be described in  FIG. 6 . Both type A and B versions use an automated titrator  132  to supply drilling fluid samples to the respective test fluid containers in the modular ADF test unit  130 . Fluids for which tests are completed are sent to the reservoir  12  via a conduit  136 . The outputs of the modular ADF test unit  130  are transmitted to the computer system  104  for processing and storage, preparation of reports, communicating results and other information via the network  20  to a remote office or location. The computer system  104  may be connected to a display  110  and a database  112 , and also to the various instruments and components via cable  114  containing control and data lines for controlling the Modes I and II test units  134 A and  134 B and receiving data from the ADFA  10 . 
         [0040]    The computer system  104 , which may comprise a workstation such as a desktop computer configured with operating program software and communications and database components, may also be coupled through a system hub  116  to the manifold system  42 . The system hub  116  functions as an active interface between the computer system  104  that is controlled by comprehensive software and the hardware elements of the system. While the system hub  116  may be coupled to an on-site database, it may also be linked through the communications system to external databases or offices.  FIG. 4  thus includes the data control lines for controlling the instruments through actuators connected to the fluid lines. Persons skilled in the art will recognize that the data lines shown may actually resemble a system bus through which both control data and instrument data may be routed. 
         [0041]    As noted previously, the system hub  116  functions as an interface between the computer system  104  and the instruments depicted in  FIG. 4 . Thus, the combination of the computer system  104  and the system hub  116  comprise the main control section of the system  10 . The communications interface  108  operates with external elements to enable remote operation, control, and analysis. In most cases, an on-site mud engineer or technician is not required because the system is highly automated by software control. The architecture of the system permits a wide variety of measurement instruments to be controlled by the system. The instruments may be selected from devices specifically designed for high-accuracy measurements. 
         [0042]      FIGS. 5A and 5B  together illustrate a pictorial diagram of a first version, type A of the modular automated test unit  130  of  FIG. 4  configured for a first mode—Mode I—of operation according to one embodiment of the invention. This embodiment will be identified by reference number  200  in  FIGS. 5A and 5B , which is essentially the same unit referenced by number  134 A. The components of test unit  200  may preferably be contained in a single housing  202 . The test unit  200  includes first and second rotating turntables  204  and  206  that are coupled to a common drive shaft  210  driven by a motor (not shown) within a base  208  in the lower part of the housing  202 . The common shaft  210  is connected to a sub-base  212  at its upper end. The first (upper) rotating turntable  204  is supported by the sub-base  212 . The first rotating turntable  204  includes positions for eight test sample cups  220  equally spaced around the perimeter of the turntable  204 . The second rotating turntable  206  includes positions for eight test tubes  240  for fluid samples equally spaced around the perimeter of the turntable  206 . 
         [0043]    Continuing with  FIGS. 5A and 5B , a vacuum pump  260  mounted on the housing  202  withdraws fluid samples from the sample cups  220  through a passage  264  and routes it through a condenser  270  to be deposited into a test tube  242  positioned just below the condenser  270 . A gas jet  262  provides for blowing CO2/N2 into the test sample cup  220  placed in position below the gas jet  262 . This burst of gas is provided during Mode I to facilitate pressurizing the sample after it is heated to a predetermined temperature and before the test sample cup  220  is sealed and pressurized for testing. A density float sensor  250 , suspended within the housing  202  just above a test tube  244 , inserts first  246  and second  248  density floats into the test tube  244  to gage the density of the drilling fluid sample. Float  246  has a density of 5.0 ppg and float  248  has a density of 8.3 ppg. Drilling fluid samples are supplied to the test sample cups  220  in the first turntable  204  by an automated titrator  280  that may be positioned above the test sample cup  220  along rails supported by brackets  284  of the test unit  200 . The titrator  280  may be operated by a solenoid or other device (not shown) under control by the computer  104 . 
         [0044]    The first rotating turntable  204  of  FIGS. 5A and 5B  includes features for heating, insulating, spinning, and sealing a sample cup  220  after a sample container  290  is installed and a drilling fluid sample is deposited in the sample container  290 . The sample container  290  preferably includes squares of a filtration paper  294  placed within the sample container  290  and retained by clips or slots (not shown) provided for that purpose. The sample container  290  has walls with openings  292  arranged in a grid pattern to permit filtrate to pass from the sample container  290  when the test sample cup  220  is spun during testing. The test sample cups  220  are supported in the rotating turntable  204  in one of eight positions disposed around the perimeter of the turntable. The test sample cups  220  are each surrounded by insulation  222 . In the lower part of each sample cup  220  is a heating element  224  surrounding a driven magnet  226 . Surrounding the upper rim inside each sample cup  220  are one or more flexible rotary shaft seals for sealing the space within the sample cup  220  and the outside of the sample container  290  when it is installed within the sample cup  220 . The driven magnet  226  that is caused to spin by a motor mechanism (not shown). The motor may have a drive magnet  227  similar to the drive magnet  226  but attached to an output shaft so that spinning the drive magnet  227  causes the driven magnet  226  to rotate by the interacting magnetic fields as is well understood by persons skilled in the art. Alternatively, the output shaft of the motor may be attached to the driven magnet  226 , either directly or through a gear reduction assembly. 
         [0045]    Referring to  FIGS. 5A and 5B , the modular automated drilling fluid analysis unit  200  operates in Mode I as follows to perform the following tests: (1) filtration; (2) fluid test; (3) filter cake; (4) density; and (5) volume. 
         [0046]    Initializing the apparatus proceeds according to the following steps: (A) install a pre-sized filter paper element (for example, two squares of Whatman® #50 filter paper) into two sides of each test cup  290  of the first turntable  204  using the retaining clips or slots in the test cups, and load the prepared test cups  290  into the test cup chambers  220  disposed around the periphery of the rotating turntable  204 , making sure the periphery seals  228  are correctly sealing the test cups. (B) Install clean test tubes  240  into the receptacles of the second turntable  206 . (C) Enter the time and date, along with other data such as type of fluid, start time, operating temperature (typically 120 degrees for water based mud; 150 degrees for oil based mud), rotation speed, length of test, test volume, etc. on the workstation  90  or on a control pad (not shown) that may be coupled to the ADFA unit  200 . 
         [0047]    (D) Initiate filling of the test cups by the automated titrator  280  (or by hand if necessary). (E) Advance the turntable to align the test cup with the vacuum pump station  260  for heating the fluid to the preset temperature, followed by (F) “blow down” of the CO2/N2. Then, (G) pressurize the test cup up to 250 psi (pounds per square inch”) and (H) spin the test cup at a predetermined speed between 0 and 200 rpm. This completes the filtering step to produce the filtrate that leads to measuring the thickness of the filter cake deposited on the filter paper during the spinning operation. 
         [0048]    (I) Route the fluid after filtering through the vacuum pump  260  and the condenser  270  (to cool the fluid) and into the test tube to measure the density (J) and the volume (K) of fluid and solids in the second rotating turntable  206 . (L) When the tests on a test cup are completed, advance the turntables in the ADFA unit  200  to the next test position and repeat the sequence. The density (J) is measured in the test tube  244  that is supported below a density sensor  250 . Test tube  244  contains a 5.0 ppg float and a 8.3 ppg float, and the lift or position of the floats is sensed by the density sensor  250 . The sensor data for the density and depth in the test tube is analyzed by the computer  104  to convert the density measurements to proportions of water and oil in the density fluid to enable the calculation of the volume of the fluids and solids in the drilling fluid sample. When all tests are completed, the ADFA unit  200  is reset to a neutral condition in readiness for the next testing cycle. 
         [0049]      FIGS. 6A and 6B  together illustrate a pictorial diagram of a second version, type B of the modular automated test unit  130  of  FIG. 4  configured for a second mode—Mode II—of operation according to one embodiment of the invention. This embodiment will be identified by reference number  300  in  FIG. 6 , which is essentially the same unit referenced by number  134 B. The components of test unit  300  may preferably be contained in a single housing  202 . The test unit  300  includes first and second rotating turntables  304  and  306  that are coupled to a common drive shaft  210  driven by a motor (not shown) within a base  208  I the lower part of the housing  302 . The common shaft  210  is connected to a sub-base  312  at its upper end. The first (upper) rotating turntable  304  is supported by the sub-base  312 . The first rotating turntable  304  includes positions for eight test sample cups  320  equally spaced around the perimeter of the turntable  304 . The second rotating turntable  206  includes positions for eight test tubes  240  for fluid samples equally spaced around the perimeter of the turntable  206 . 
         [0050]    Continuing with  FIGS. 6A and 6B , a vacuum pump  360  mounted on the housing  202  withdraws fluid samples from the sample cups  320  through a passage  364  and routes it through a condenser  270  to be deposited into a test tube  242  positioned just below the condenser  270 . A gas conduit  362  provides for blowing CO2/N2 over the test sample cup  320  placed in position below the gas jet  362 . This burst of gas is provided during Mode II to facilitate evaporation of the air near the surface of the fluid sample after it is heated to a predetermined temperature and before the test sample cup  320  is evacuated for testing. A density float sensor  250 , suspended within the housing  202  just above a test tube  244 , inserts first  246  and second  248  density floats into the test tube  244  to gage the density of the drilling fluid sample. Float  246  has a density of 5.0 ppg and float  248  has a density of 8.3 ppg. Drilling fluid samples are supplied to the test sample cups  220  in the first turntable  204  by an automated titrator  280  that may be positioned above the test sample cup  320  along rails  282  supported by brackets  284  of the test unit  200 . The titrator  280  may be operated by a solenoid or other device (not shown) under control by the computer  104 . 
         [0051]    The first rotating turntable  304  of  FIGS. 6A and 6B  includes features for determining the volume amount of water, oil, and solids in the drilling fluid sample deposited in the beaker  320 . Each beaker  320 , preferably made of stainless steel, is supported at an angle—preferably approximately 55 degrees from vertical—to maximize the surface area of the drilling fluid exposed to a vacuum for increasing evaporation of the drilling fluid. The test sample cups  220  are supported in the rotating turntable  204  in one of eight positions disposed around the perimeter of the turntable. Each sample beaker  320  is surrounded by insulation  322  to minimize the effects of ambient temperatures on the sample drilling fluid. The sample fluid beaker is advanced into position to be enclosed within a test chamber (not shown for clarity), which can be evacuated by a vacuum pump  360 . The evaporation process can be facilitated or sped up by introducing CO2/N2 “blown down” via a gas conduit  362 . Following the evaporation steps, the evaporated drilling fluid is withdrawn by the vacuum pump  360  through passage  364  and into the condenser  270  to be cooled before depositing it into a test tube  240 . 
         [0052]    Referring to  FIGS. 6A and 6B , the modular automated drilling fluid analysis unit  300  operates in Mode II as follows to perform the following tests: (1) volume of water, (2) volume of oil; and (3) volume amount of solids. These tests are used to determine the percentages of fluids in the drilling fluid (mud) sample. The set up and initialization procedures are similar to the procedure for the Mode I operation depicted in  FIGS. 5A and 5B . 
         [0053]    Initializing the apparatus proceeds according to the following steps: (A) install a stainless steel beaker  320  into each angled chamber disposed around the periphery of the rotating turntable  304 . (B) Install clean test tubes  240  into the receptacles of the second turntable  206 . (C) Enter the time and date, along with other data such as type of fluid, start time, operating temperature (typically 120 degrees for water based mud; 150 degrees for oil based mud), rotation speed, length of test, test volume, etc. on the workstation  90  or on a control pad (not shown) that may be coupled to the ADFA unit  200 . 
         [0054]    (D) Initiate filling of the test beakers  320  by the automated titrator  280  (or by hand if necessary). (E) Advance the turntable to align the test beaker  320  with the vacuum pump station  260  for heating the fluid to the preset temperature, followed by (F) “blow down” of the CO2/N2. Then, (G) allow the evaporation to occur while (H) subjecting the sample in the beaker  320  to a vacuum to reduce the pressure. 
         [0055]    (I) Route the evaporated fluid through the vacuum pump  260  and the condenser  270  (to cool the fluid) and into the test tube to measure the density (J) and the volume (K) of fluid and solids in the second rotating turntable  206 . (L) When the tests on a test sample are completed, advance the turntables in the ADFA unit  200  to the next test position and repeat the sequence. The density (J) is measured in the test tube  244  that is supported below a density sensor  250 . Test tube  244  contains a 5.0 ppg float and a 8.3 ppg float, and the lift or position of the floats is sensed by the density sensor  250 . The sensor data for the density and depth of fluid in the test tube  244  is analyzed by the computer  104  to convert the density measurements to proportions of water and oil in the density fluid to enable calculation of the volumes of fluids and solids in the drilling fluid sample. When all tests are completed, the ADFA unit  200  is reset to a neutral condition in readiness for the next testing cycle. 
         [0056]    The foregoing description, read in reference to the accompanying drawings discloses a mobile, automated drilling fluid analysis system that continuously performs analysis tests in sequence and periodically at timed intervals, and stores the data in a database, comprising a housing disposed on a mobile frame that is configured for connections to electrical power, and a fluid conduit system from and to a drilling fluid reservoir. A computer system disposed within the housing and configured with non-volatile storage, a communications interface to a network, and a suite of program software for controlling operations of the analysis system is included to measure, analyze, store, communicate, and compose output displays, summaries, and reports thereof through graphical peripherals and remote connections to the system. The system further includes a modular automated test unit enclosed within the housing and coupled through a manifold to the fluid conduits system, the automated test unit having a dual, motor-driven turntable including a first turntable for measuring physical parameters and a second turntable for measuring chemical parameters. The automated test unit also includes a metering mechanism for depositing drilling fluid samples pumped through the fluid conduits from the drilling fluid reservoir into test containers on the first or second turntables; wherein the automated test unit provides for receiving, sensing, and measuring multiple physical and chemical parameters of the drilling fluid samples in a prescribed, continuous sequence according to analysis routines of the program software and compiling the analyzed parameters for storage or display. 
         [0057]    In one aspect the modular automated test unit may be constructed as a self-contained unit configured for operating in several alternative modes depending on the particular combination of tests the ADFA system  10  is set up to perform. As noted previously, the system may be configured to operate unattended, continuously according to a predetermined sequence of tests. 
         [0058]    While the invention has been shown in only one of its forms, it is not thus limited but is susceptible to various changes and modifications without departing from the spirit thereof.