Abstract:
A method of monitoring a fluid system of a mining machine. The method including sensing a pressure level of a fluid in the fluid system of the mining machine to generate pressure level data; analyzing the pressure level data to detect pressure level deviations; determining at least one selected from the group of when a frequency of the pressure level deviations exceeds a predetermined frequency, and when the fluid pressure level fails to reach a threshold within a predetermined reaction time period; and outputting an alert in response to the determination.

Description:
RELATED APPLICATION 
       [0001]    The present application claims priority to U.S. Provisional Application 61/766,080, filed Feb. 18, 2013, the entire contents of which are hereby incorporated. 
     
    
     BACKGROUND 
       [0002]    The present invention relates to an air and lubricant monitoring system for mining equipment, such as shovels. 
       SUMMARY 
       [0003]    Finely-tuned air and lubricant systems provide optimal productivity and operation of mining equipment, such as a shovel. Accordingly, embodiments of the present invention monitor air pressure using either a pressure transducer or pressure switch. If the air pressure in the system drops below original equipment manufacturer (“OEM”) specs for more than a predetermined period of time (e.g., approximately two seconds) during operation, a controller included in the shovel can initiate a delayed shutdown, which stops the shovel in approximately 30 seconds. Appropriate setting of the air pressure at the compressors and the behavior of the air system in combination with the shovel&#39;s brakes and lubricant systems help determine key performance indicators (“KPIs”) for the shovel that can be used to manage the operation of the shovel. 
         [0004]    In particular, specific trend behaviors of the air pressure system, brakes release indicators, brakes solenoids, brakes pressures, and lubricant systems can be recorded and analyzed. Oscillations or sizable drops in the air pressure are generally primary indicators of any anomaly in the air system or related components. The outliers are filtered while the machine is either in a shutdown sequence or in an idle mode that is determined by the machine&#39;s state digital signal codes. Essentially, the minimum setting is the first check point taken into consideration to begin with and prior to any digging into brakes and lubricant analytics. 
         [0005]    Although observing and analyzing the air pressure system and the related subsystems in approximately real-time provides benefits, automatic predictive failure analysis provides additional advantages. In particular, condition-based equipment models (“CBEMs”) can be used to predict and notify operators of any potential problems or failures. The condition based models look for specific changes in the functionality of the shovel and the related systems that might indicate the potential of a future problem or failure. 
         [0006]    For example, brake set and release times are some of the characteristics the predictive model programs can analyze. For example, correlating anomalies in the air pressure with the delayed brakes release mechanisms on the hoist and crowd motions can help determine if the brakes air supply regulator needs to be adjusted. Historical data analysis indicates that it could take approximately 0.7 seconds to 1.2 seconds from the time an operator initiates a brake release function until the motion is halted. During this time, brakes supply regulator is presumed to be set around 100 PSIs. Although it would be nearly impossible for an analyst to actively monitor the brake system set and release times for slight changes, indicating a potential failure, the predictive models are analyzing this data continuously. 
         [0007]    Similarly, the lubricant system, including the upper and lower open grease systems, are tied to the air system. Leaks in the lubricant system air supply, as well as, insufficient lubricant pressures and functionality can be analyzed and determined. As the time-series data is collected, statistical assessment with the historically-derived control parameters, help detect any deviation each time a dip or spike behavior is logged. For example, improper grease levels have been determined to be secondary indicators of improper functioning of the air and lubricant systems. 
         [0008]    Monitoring the above mentioned KPIs and processing them in approximately real-time can detect out-of-normal settings and indiscernible changes. Advanced and early prognostics supported by proven diagnostics (e.g., based on access to a large amount of data different mechanical settings) further intensify the analytics. All of this functionality helps rule out the obvious, and not so obvious, in a prompt fashion, which reduces unwanted downtime resulting in loss of production. 
         [0009]    Accordingly, one model (an air pressure model) is used to detect dips and spikes in pressure. An alert is generated based on both the amount of deviation from expected pressure level and the frequency of deviations in a timer period. Another model (a lubricant system pressure model) detects a dip in air pressure when lubricant action has activated. An alert is generated if the dip is excessive. Yet another model (a lubricant system cycle time model) determines if dips in air pressure occurring when lubricant action is activated remain for an excessive period of time. A further model (a lubricant system reaction time model) determines an amount of time it takes to reach appropriate pressure levels when lubricant action is activated. An alert is generated if the amount of time is excessive. 
         [0010]    In one embodiment, the invention provides a mining machine including fluid system. The mining machine including a fluid pressure sensor operable to sense a pressure level of a fluid in the fluid system of the mining machine and a controller. The controller operable to analyze the pressure level to detect pressure level deviations; determine at least one selected from the group of when a frequency of the pressure level deviations exceeds a predetermined frequency, and when the fluid pressure level fails to reach a threshold within a predetermined reaction time period; and output an alert in response to the determination. 
         [0011]    In another embodiment the invention provides a method of monitoring a fluid system of a mining machine. The method including sensing a pressure level of a fluid in the fluid system of the mining machine to generate pressure level data; analyzing the pressure level data to detect pressure level deviations; determining at least one selected from the group of when a frequency of the pressure level deviations exceeds a predetermined frequency, and when the fluid pressure level fails to reach a threshold within a predetermined reaction time period; and outputting an alert in response to the determination. 
         [0012]    Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  illustrates a mining shovel according to an embodiment of the invention. 
           [0014]      FIG. 2  illustrates a control system of the mining shovel of  FIG. 1 . 
           [0015]      FIG. 3  illustrates an air system of the mining shovel of  FIG. 1 . 
           [0016]      FIG. 4  illustrates a lubricant system of the mining shovel of  FIG. 1 . 
           [0017]      FIG. 5  illustrates an air pressure monitoring process or method according to an embodiment of the invention. 
           [0018]      FIG. 6  illustrates a lubricant pressure monitoring process or method according to an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein are meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. 
         [0020]    In addition, it should be understood that embodiments of the invention may include hardware, software, and electronic components or modules that, for purposes of discussion, may be illustrated and described as if the majority of the components were implemented solely in hardware. However, one of ordinary skill in the art, and based on a reading of this detailed description, would recognize that, in at least one embodiment, the electronic based aspects of the invention may be implemented in software (e.g., stored on non-transitory computer-readable medium). As such, it should be noted that a plurality of hardware and software based devices, as well as a plurality of different structural components may be utilized to implement the invention. Furthermore, and as described in subsequent paragraphs, the specific mechanical configurations illustrated in the drawings are intended to exemplify embodiments of the invention and that other alternative mechanical configurations are possible. 
         [0021]      FIG. 1  illustrates a mining shovel  100 , such as an electric mining shovel. The embodiment shown in  FIG. 1  illustrates the mining machine as a rope shovel, however, in other embodiments the mining shovel  100  is a different type of mining machine, such as for example, a hybrid mining shovel, a dragline excavator, etc. The mining shovel  100  includes tracks  105  for propelling the rope shovel  100  forward and backward, and for turning the rope shovel  100  (i.e., by varying the speed and/or direction of the left and right tracks relative to each other). The tracks  105  support a base  110  including a cab  115 . The base  110  is able to swing or swivel about a swing axis  125 , for instance, to move from a digging location to a dumping location. Movement of the tracks  105  is not necessary for the swing motion. The rope shovel further includes a dipper shaft  130  supporting a pivotable dipper handle  135  (handle  135 ) and dipper  140 . The dipper  140  includes a door  145  for dumping contents from within the dipper  140  into a dump location, such as a hopper or dump-truck. 
         [0022]    The rope shovel  100  also includes taut suspension cables  150  coupled between the base  110  and dipper shaft  130  for supporting the dipper shaft  130 ; a hoist cable  155  attached to a winch (not shown) within the base  110  for winding the cable  155  to raise and lower the dipper  140 ; and a dipper door cable  160  attached to another winch (not shown) for opening the door  145  of the dipper  140 . In some instances, the rope shovel  100  is a Joy Global Surface Mining® 4100 series shovel produced by Joy Global Inc., although the electric mining shovel  100  can be another type or model of mining equipment. 
         [0023]    When the tracks  105  of the mining shovel  100  are static, the dipper  140  is operable to move based on three control actions, hoist, crowd, and swing. The hoist control raises and lowers the dipper  140  by winding and unwinding hoist cable  155 . The crowd control extends and retracts the position of the handle  135  and dipper  140 . In one embodiment, the handle  135  and dipper  140  are crowded by using a rack and pinion system. In another embodiment, the handle  135  and dipper  140  are crowded using a hydraulic drive system. The swing control swivels the handle  135  relative to the swing axis  125 . Before dumping its contents, the dipper  140  is maneuvered to the appropriate hoist, crowd, and swing positions to 1) ensure the contents do not miss the dump location; 2) the door  145  does not hit the dump location when released; and 3) the dipper  140  is not too high such that the released contents would damage the dump location. 
         [0024]    As shown in  FIG. 2 , the mining shovel  100  includes a control system  200 . The control system  200  includes a controller  205 , operator controls  210 , mining shovel controls  215 , sensors  220 , a user-interface  225 , and other input/outputs  230 . The controller  205  includes a processor  235  and memory  240 . The memory  240  stores instructions executable by the processor  235  and various inputs/outputs for, e.g., allowing communication between the controller  205  and the operator or between the controller  205  and sensors  220 . The memory  240  includes, for example, a program storage area and a data storage area. The program storage area and the data storage area can include combinations of different types of memory, such as read-only memory (“ROM”), random access memory (“RAM”) (e.g.,, dynamic RAM [“DRAM”], synchronous DRAM [“SDRAM”], etc.), electrically erasable programmable read-only memory (“EEPROM”), flash memory, a hard disk, an SD cark, or other suitable magnetic, optical, physical, or electronic memory devices. The processor  235  is connected to the memory  240  and executes software instructions that are capable of being stored in the memory  240 . Software included in the implementation of the mining shovel  100  can be stored in the memory  240  of the controller  205 . The software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. The controller  205  is configured to retrieve from memory  240  and execute (with the processor  235 ), among other things, instructions related to the control processes and methods described herein. In some instances, the processor  235  includes one or more of a microprocessor, digital signal processor (DSP), field programmable gate array (FPGA), application specific integrated circuit (ASIC), or the like. In some embodiments, the controller  205  also includes one or more input/output interfaces for interfacing with the operator controls  210 , the mining shovel controls  215 , the sensors  220 , the user-interface  225 , and the other input/outputs  230 . 
         [0025]    The controller  205  receives input from the operator controls  210 . The operator controls  210  include a propel control  242 , a crowd control  245 , a swing control  250 , a hoist control  255 , and a door control  260 . The propel control  242 , crowd control  245 , swing control  250 , hoist control  255 , and door control  260  include, for instance, operator controlled input devices such as joysticks, levers, foot pedals, and other actuators. The operator controls  210  receive operator input via the input devices and output digital motion commands to the controller  205 . The motion commands include, for example, left track forward, left track reverse, right track forward, right track reverse, hoist up, hoist down, crowd extend, crowd retract, swing clockwise, swing counterclockwise, and dipper door release. 
         [0026]    Upon receiving a motion command, the controller  205  generally controls mining shovel controls  215  as commanded by the operator. The mining shovel controls  215  include one or more propel motors  262 , one or more crowd motors  265 , one or more swing motors  270 , and one or more hoist motors  275 . The mining shovel controls  215  further include one or more propel brakes  263 , one or more crowd brakes  266 , one or more swing brakes  271 , and one or more hoist brakes  276 , which are used to decelerate the respective movements of the mining shovel  100 . In some embodiments, the brakes are electrically controlled brakes (e.g., solenoid brakes). In embodiments where the brakes are solenoid brakes, a spring engages the brake when the solenoid is powered off, and the brake is disengaged, or released, when the solenoid is powered on. In other embodiments, the brakes are air brakes (e.g., compressed air brakes). In embodiments where the brakes are air brakes, compressed air is used to apply pressure to a brake pad. In other embodiments, the brakes include one or more solenoid brakes and one or more air brakes. For instance, if the operator indicates via swing control  250  to rotate the handle  135  counterclockwise, the controller  205  will generally control the swing motor  270  to rotate the handle  135  counterclockwise. Once the operator indicates via swing control  250  to decelerate the handle  135 , the controller  205  will generally control the swing brake  271  to decelerate the handle  135 . However, in some embodiments, the controller  205  is configured to limit the operator motion commands and generate motion commands independent of the operator input. 
         [0027]    The controller  205  is also in communication with the sensors  220  to monitor the location and status of the dipper  140 . For example, the controller  205  is in communication with one or more propel sensors  278 , one or more crowd sensors  280 , one or more swing sensors  285 , and one or more hoist sensors  290 . The propel sensors  278  indicate to the controller  205  data (e.g., position, speed, directions, etc.) concerning the tracks  105 . The crowd sensors  280  indicate to the controller  205  the level of extension or retraction of the dipper  140 . The swing sensors  285  indicate to the controller  205  the swing angle of the handle  135 . The hoist sensors  290  indicate to the controller  205  the height of the dipper  140  based on the hoist cable  155  position. In other embodiments there are door latch sensors which, among other things, indicate whether the dipper door  145  is open or closed and measure the weight of a load contained in the dipper  140 . 
         [0028]    The mining shovel  100  further includes one or more fluid systems used to control, or maintain, machine health or functionality. For example, an air system  300  ( FIG. 3 ) supplies compressed air to various areas or components of the mining shovel  100 . Another example of a fluid system is a lubricant system  400  ( FIG. 4 ), which supplies lubricant to various areas or components of the mining shovel  100 . In some embodiments, the fluid systems pressurize fluid and supply the pressurized fluid to various components of the mining shovel  100 . In other embodiments, the fluid system may include an air, oil, or water based cooling or hydraulic control system. 
         [0029]    As shown in  FIG. 3 , the controller  205  is further in communication with an air system  300  (e.g., as one of the other input/outputs  230 ). The air system  300  supplies filtered, dried, and lubricated compressed air, as required, to all the air operated components of the mining shovel  100  (e.g., operator cab seat, air horns, air stair, lubricant pump air motors, lubricant system air sprayers, air brakes, air driven cable reel, a filtration system, etc.). 
         [0030]    The air system  300  includes a compressor  305 , an air dryer  310 , an air receiver  315 , one or more air valves  320 , a lubricator  325 , an air manifold  330 , one or more air regulators  335 , and a swivel  340 . The variety of elements of the air system  300  are connected via a plurality of air lines. For example, in operation, the compressed air flows through the air system  300  to the various components via the air lines. The air lines and the direction of the flow therethrough are represented by the arrows connecting the plurality of elements of the air system  300  in  FIG. 3 . It should be understood that, in some embodiments, the air system  300  includes more or less elements. 
         [0031]    The compressor  305  is an air compressor used to supply air to the air system  300 . In some embodiments, the compressor  305  is a single compressor system. In other embodiments, the compressor  305  is a dual compressor system. The air dryer  310  removes moisture from the air supplied by the compressor  305  to prevent contamination within the air system  300 . The air receiver  315  is a pressure vessel, or tank, used to store the air supplied by the compressor  305 . 
         [0032]    The one or more air valves  320  can include a variety of air valves, such as diaphragm valves, flow control valves, isolator valves, pilot valves, shutoff valves, or solenoid valves. Diaphragm valves contain a diaphragm, or membrane, that opens/closes the valve. Flow control valves are used to regulate the flow or pressure of air within the air system  300 . Isolator valves are used to separate various components from the rest of the air system  300 , in the case of failure or when maintenance is required on a component. Pilot valves allow high pressure or high flow systems to be controlled at a lower pressure or low flow. The shutoff valve is a valve that controls the on/off supply to the air system  300 . In some embodiments, the mining shovel  100  includes more or less valves. 
         [0033]    The lubricator  325  is used to add lubricant to the air, which is necessary for the moving parts of the various air valves and cylinders in the air system  300 . The air manifold  330  branches the air from the air receiver  315  to various components of the mining shovel  100 . The air regulators  335  are used to lower the air pressure from the air receiver  315  before the air is sent downstream to the various components. The swivel  340  is a mechanical joint that allows the upper portion of the mining shovel  100  to rotate about the lower portion of the mining shovel  100  without damaging various air hoses as well as electrical cabling running between the lower portion and the upper portion. 
         [0034]    In operation, the compressor  305  compresses and pressurizes air into the air receiver  315 . As the air is supplied to the air receiver  315 , the air dryer  310  removes moisture from the air. The dry air is then supplied through the one or more valves  320 . In some embodiments, there are other valves  320  placed in various positions of the air system  300 . The dry air is then supplied through the lubricator  325 , which adds lubricant to the air. The air is then branched out to the various components by the air manifold  330 . If a component requires a lower air pressure, the air is sent through an air regulator  335  before reaching the component. If a component is located in the upper portion of the mining shovel  100 , the air is passed through the swivel  340 . If a component is located in the lower portion of the mining shovel  100 , the air is not passed through the swivel  340 . It should be understood that, in some embodiments, the various components of the air system  300  can be arranged in various configurations, and thus perform functionality in a different order that as noted above. For example,  FIG. 3  illustrates air being transported to a component, a component through a regulator  335 , a component through a regulator  335  and the swivel  340 , and a component through the swivel  340 . 
         [0035]    The air system  300  further includes one or more air sensors  350  placed at various positions within the air system  300 . In some embodiments, the air sensors  350  are transducers, which measure pressure levels and convert the pressure levels to electrical signals. For example, an air sensor  350  measures the air pressure of the air system  300 . Although shown in  FIG. 3  as being located between the air receiver  315  and air valves  320 , in some embodiments, there are multiple air sensors  350  placed throughout the air system  300 . 
         [0036]    In some embodiments, the air sensors  350  are electrically connected to the controller  205  (e.g., as one of the other input/outputs  230 ). The controller  205  receives the electrical signal from the air sensors  350 . In some embodiments, the controller  205  detects dips and spikes in the sensed air pressure of the air system  300  (e.g., using one or more condition-based equipment models (“CBEMs”) noted above). The controller  205  determines if there is an issue, or a fault, with the sensed air pressure. If the controller  205  determines that there is an issue with the sensed air pressure, such as a current failure, or a possible future failure, the controller  205  indicates the issue to the operator via the user-interface  225 . 
         [0037]    In some embodiments, the controller  205  is further connected to a server  360  via a network (e.g., a local area network, a wide area network, a wireless network, the Internet, etc. or combinations thereof). The controller  205  outputs the sensed air pressure to the server  360 . The server  360  detects dips and spikes in the sensed air pressure (e.g., using one or more CBEM) to determine if there is an issue. If there is an issue, the server  360  indicates the issue to the operator. In some embodiments the issue is indicated to the operator via the user-interface  225 . In other embodiments, the server  360  indicates an issue to the operator via remote messaging (e.g., electronic mail). In other embodiments, the server  360  indicates an issue to a remote user-interface. In some embodiments, the issue is indicated to the operator via a variety of methods discussed above. 
         [0038]    As an example, in some embodiments, the main air pressure of the air system  300  is detected via the air sensor  350 . In such an embodiment, the controller  205  detects dips and spikes in the main air pressure of the air system  300 . The controller  205  determines if there is an issue by calculating the deviation of the sensed air pressure from a first predetermined air pressure threshold (e.g., the OEM specs, approximately 110 psi for AC shovels, approximately 100 psi for DC shovels, etc.) along with the frequency of deviations in a predetermined air pressure time period. For example, the main air pressure is sensed every two seconds, if the sensed air pressure is below the first predetermined air pressure threshold over two consecutive readings an issue is detected. As another example, the main air pressure is sensed every two seconds, if the sensed air pressure falls below the first predetermined air pressure threshold a predetermined amount of times in a predetermined time period, an issue is detected. If the controller  205  determines that there is an issue with the main air pressure, the controller  205  outputs an indication, or an alert. 
         [0039]    In some embodiments, the controller  205  determines if there is an issue, or fault, based on a plurality of factors. The factors include, but are not limited to: air system pressure, air system cycle time, and air system reaction time. The controller  205  may determine there is an issue if the sensed air pressure of the air system  300  goes above or below the first predetermined air pressure threshold. The controller  205  may further determine there is an issue if the air pressure of the air system  300  goes above or below a second predetermined air pressure threshold for a predetermined air pressure time period. The controller  205  may further determine there is an issue if, at the beginning of a lubricant cycle, the air pressure does not reach a third predetermined air pressure threshold within a predetermined air pressure reaction time period. 
         [0040]    As shown in  FIG. 4 , the controller  205  is further in communication with a lubricant system  400 . In some embodiments, the controller  205  is electrically connected to the lubricant system  400  via the other input/output  230 . The lubricant system  400  supplies lubricating grease (e.g., lubricant, etc.) to various components of the mining shovel  100  (e.g., boom point sheave, fleeting sheave, shipper shaft bushings, saddle block bushings, center gudgeon bushings and washers, swing shaft bearings, hoist drum sidestand bearings, boom foot pins, front and rear idler bushings, lower roller bushings, final drive shaft bearings and washers, handle rack and pinion, saddle block wear plates, boom wear plates, roller circle, ring gear, etc.). The lubricant flows through the lubricant system  400  to the various components of the mining shovel  100  via a plurality of grease, or lubricant lines. The lubricant lines and the direction of the flow therethrough are represented by the arrows connecting the plurality of elements of the lubricant system  400  in  FIG. 4 . 
         [0041]    The lubricant system  400  includes one or more grease tanks  405 , one or more lubricant pumps  410 , one or more lubricant valves  415 , and the swivel  340 . In the embodiment shown in  FIG. 4 , the lubricant system  400  provides lubricant to an upper grease system  430  and a lower grease system  435 . The upper grease system  430  includes the components of the mining shovel  100  that are located in the upper portion of the mining shovel  100 . The lower grease system  435  includes components of the mining shovel  100  that are located in the lower portion of the mining shovel  100 . In some embodiments, the lubricant system  400  includes more or less components. 
         [0042]    The grease tank  405  is a vessel, or tank, for storing the lubricant of the lubricant system  400 . The lubricant pump  410  is a pump for moving the lubricant from the grease tank  405  through the lubricant system  400 . The one or more lubricant valves  415  include a variety of lubricant valves, such as, flow control valves, solenoid valves, vent valves, and zone control valves. The flow control valves are used to regulate the flow or pressure of the lubricant. The solenoid valves are valves that are controlled by electrical signals. The vent valves are solenoid valves that allow pressure in the lubrication zones to exhaust back to the grease tank  405 . The zone control valves are solenoid valves that allow lubricant to flow to specific areas of the mining shovel  100 . In some embodiments, the mining shovel includes four zones: the four zones including the upper grease zone, the lower grease zone, the upper open gear zone, and the lower open gear zone. 
         [0043]    In some embodiments, each zone is lubricated according to a lubrication cycle. The lubrication cycle for each zone is set to run automatically as the timer for each cycle reaches its set point and additional prerequisites are met based on logic of the control system  200 . The time between each cycle can be set according to a predetermined cycle time (e.g., one minute, three minutes, five minutes, ten minutes, fifteen minutes, thirty minutes, etc.). In some embodiments, the predetermined cycle time varies from zone to zone. 
         [0044]    In operation, when a lubricant cycle begins, lubricant is pumped from the grease tank  405  by the lubricant pump  410 . Various lubricant valves  415  are opened, for example but not limited to, by an electrical signal from the controller  200 . In some embodiments, the lubricant valve  415  is one of the zone control valves, which open in order to allow lubricant to flow to the corresponding zone. In such an embodiment, the other zone control valves are normally closed and remain closed. The lubricant pump  410  then pumps the lubricant to the corresponding zone for the predetermined cycle time. The lubricant is then provided to the various components of the mining shovel  100  in the corresponding zone of upper grease system  430  or the lower grease system  435 . In some embodiments, compressed air from the air system  300  is pushed through the opened lubricant valve  415  prior to lubricant being pumped through the corresponding opened lubricant valve  415 . In some embodiments, after lubricant is provided to the various components, the lubricant is purged from the lubricant system  400  via compressed air from the air system  300 . Excess lubricant from the various components flows through a vent valve back to the grease tank  405 . A similar lubricant cycle for the remaining zones is then performed. 
         [0045]    The lubricant system  400  further includes lubricant sensors  450  placed at various positions within the lubricant system  400 . In some embodiments, the lubricant sensors  450  are transducers that measure pressure levels and convert the pressure levels to electrical signals. In some embodiments, the lubricant sensors  450  are ultrasonic transducers, which are used to measure distances. In some embodiments, lubricant sensor  450  measures a lubricant pressure of the lubricant system  400 . Although shown in  FIG. 4  as being located between the lubricant pump  410  and lubricant valves  415 , in some embodiments, there are multiple air sensors  450  placed throughout the lubricant system  400 . 
         [0046]    In some embodiments, the lubricant sensors  450  are electrically connected to the controller  205  (e.g., as one of the other input/outputs  230 ). The controller  205  receives the electrical signal from the lubricant sensors  450 . In some embodiments, the controller  205  detects dips and spikes in the sensed lubricant pressure of the lubricant system  400 . 
         [0047]    The controller  205  determines if there is an issue with the sensed lubricant pressure by monitoring the lubricant pressure, the lubricant system cycle time, and the lubricant system reaction time (e.g., using one or more CBEMs). The lubricant pressure is monitored for excessive dips or spikes, which may indicate an issue. The lubricant system cycle time is the period of time of a dip. If the time period of the dip is excessive, there may be an issue. The lubricant system reaction time is the amount of time for the lubricant system  400  to reach appropriate pressure levels. If the time is excessive there may be an issue. If the controller  205  determines that there is an issue with the sensed lubricant pressure, such as a current failure, or a possible future failure, the controller  205  indicates to the operator via the user-interface  225 . 
         [0048]    As noted above, in some embodiments, the controller  205  is further connected to the server  360 . The controller  205  can output the sensed lubricant pressure to the server  360 . The server  360  detects (e.g., using one or more CBEMs) dips and spikes in the sensed lubricant pressure to determine if there is an issue. If there is an issue, the server  360  indicates the issue to the operator. In some embodiments the issue is indicated to the operator via the user-interface  225 . In other embodiments, the server  360  indicates an issue to the operator via remote messaging (e.g., electronic mail). In other embodiments, the server  360  indicates an issue to a remote user-interface. In some embodiments, the issue is indicated to the operator via a variety of methods discussed above. 
         [0049]    As an example, in some embodiments, the lubricant pressure of the lubricant system  400  is detected via one or more lubricant sensors  450 . In some embodiments, the lubricant pressure is not detected until after a predetermined time period (e.g., one minute, two minutes, three minutes, etc.) has surpassed after the start of a lubrication cycle. This allows for the lubricant pressure in the system to reach an upper limit set point (i.e., the OEM specs, approximately 1800 psi to 2400 psi for AC shovels). 
         [0050]    Once the predetermined time period has surpassed, the controller  205  monitors the sensed lubricant pressure of the lubricant system  400 . The controller  205  determines if there is an issue, or fault, based on a plurality of factors. The factors include, but are not limited to: lubricant system pressure, lubricant system cycle time, and lubricant system reaction time. The controller  205  may determine there is an issue if the sensed lubricant pressure of the lubricant system  400  goes above or below a first predetermined lubricant pressure threshold (i.e., lubricant system pressure). The controller  205  may further determine there is an issue if the lubricant pressure of the lubricant system  400  goes above or below a second predetermined lubricant pressure threshold for a predetermined lubricant cycle time period (i.e., lubricant pressure cycle time). The controller  205  may further determine there is an issue if, at the beginning of a lubricant cycle, the lubricant pressure does not reach the upper limit set point, discussed above, within a predetermined reaction time period (i.e., lubricant system reaction time). 
         [0051]    In some embodiments, the controller  200  monitors the various issues at various states of the lubricant cycle. For example, upon starting the cycle, the controller  200  monitors at least the lubricant system reaction time. If the reaction time is unacceptable (i.e., it is determined that there is an issue) the mining shovel  100  shuts down, or the mining shovel  100  finishes the lubricant cycle and then shuts down. 
         [0052]    If the reaction time is acceptable (i.e., it is determined there is not an issue), the controller  200  then monitors at least the lubricant system pressure and lubricant pressure cycle time. If three is an issue, the mining shovel  100  shuts down, or the mining shovel  100  finishes the lubricant cycle and then shuts down. If there is not an issue, the mining shovel  100  continues operation. 
         [0053]      FIG. 5  illustrates an embodiment of an air pressure monitoring process or method  500 . One or more air sensors  350  monitor the air pressure of the air system  300  (step  505 ). The air sensors  350  output the sensed data to the controller  205  (step  510 ). The controller  205  detects dips and spikes in the sensed air pressure (step  515 ). The controller  205  determines if there is an issue with the air pressure (step  520 ). If there is an issue, the controller  205  indicates the issue to the operator. After indicating the issue to the operator, or if there is not an issue, the controller  205  continues to monitor the air pressure of the air system  300  (at step  505 ). 
         [0054]      FIG. 6  illustrates an embodiment of a lubricant pressure monitoring process or method  600 . One or more lubricant sensors  450  monitor the lubricant pressure of the lubricant system  400  (step  605 ). The lubricant sensors  450  output the sensed data to the controller  205  (step  610 ). The controller  205  monitors the lubricant pressure, the lubricant system cycle time, and the lubricant system reaction time (step  615 ). The controller  205  determines if there is an issue with the air pressure (step  620 ). If there is an issue, the controller  205  indicates the issue to the operator. After indicating the issue to the operator, or if there is not an issue, the controller  205  continues to monitor the lubricant pressure of the lubricant system  400  (at step  605 ). 
         [0055]    Thus, the invention provides, among other things, an air and lubricant monitoring system for a mining machine, such as a mining shovel. In particular, embodiments of the invention use CBEMs to predict and notify an operator of potential problems or failures. The condition-based models look for specific changes in the functionality of the shovel and the related systems that might indicate the potential of a future problem or failure. It should be understood that the CBEMs can be executed by the controller  205  included in the shovel  100  or can be executed by the server  360  in communication with the controller  205  over one or more wired or wireless connections. Accordingly, the monitoring and predictive functionality can be provided through the controller  205 , the server  360 , or a combination thereof. 
         [0056]    In some embodiments, upon detection of an issue or fault, the controller  205  outputs an indication, or alert, which shuts down the mining shovel  100 . In some embodiments, if a lubricant cycle is currently happening, the controller  205  waits until a lubricant cycle has completed before shutting down the mining shovel  100 . In some embodiments, if a lubricant cycle has not started and the controller  205  detects an issue, the lubricant cycle will not begin. 
         [0057]    Thus, the invention provides, among other things, a system and method of monitoring an air and lubricant system. Various features and advantages of the invention are set forth in the following claims.