Patent Grant
9726017
The present invention relates to monitoring pan-line and cut horizon and shearer position of a longwall mining system.
In one embodiment, the invention provides a method of monitoring a longwall shearing mining machine in a longwall mining system, wherein the shearing mining machine includes a shearer having a first cutter drum and a second cutter drum, the method including receiving, by a processor, horizon profile data over a shear cycle. The horizon profile data includes information regarding at least one of the group comprising of a position of the shearer, a position of the first cutter drum, a position of the second cutter drum, and the pitch and roll angles of the shearer body. The method also includes analyzing the horizon profile data, by the processor, to determine whether a position failure occurred during the shear cycle based on whether the horizon profile data was within normal operational parameters during the shear cycle, and generating an alert upon determining that the position failure occurred during the shear cycle.
In another embodiment the invention provides a monitoring device for a longwall mining system including a shearer having a first cutter drum, a second cutter drum, and a first sensor to determine a position of at least one of the shearer, the first cutter drum, the second cutter drum, and the pitch and roll angles of the shearer body through-out a shear cycle. The monitoring device includes a monitoring module implemented on a processor in communication with the shearer to receive horizon profile data including information regarding at least one of the group comprising of the position of the shearer, the position of the first cutter drum, and the position of the second cutter drum. The monitoring module includes an analysis module configured to analyze the horizon profile data and to determine whether a position failure occurred during the shear cycle based on whether the horizon profile data was within normal operational parameters during the shear cycle; and an alert module configured to generate an alert upon determining that the position failure occurred during the shear cycle.
Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
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.
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) executable by one or more processors. As such, it would 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. However, other alternative mechanical configurations are possible. For example, “controllers” and “modules” described in the specification can include standard processing components, such as one or more processors, one or more computer-readable medium modules, one or more input/output interfaces, and various connections (e.g., a system bus) connecting the components. In some instances, the controllers and modules may be implemented as one or more of general purpose processors, digital signal processors DSPs), application specific integrated circuits (ASICs), and field programmable gate arrays (FPGAs) that execute instructions or otherwise implement their functions described herein.
Longwall mining begins with identifying a coal seam to be mined, then “blocking out” the seam into coal panels by excavating roadways around the perimeter of each panel. During excavation of the seam (i.e., extraction of coal), select pillars of coal can be left unexcavated between adjacent coal panels to assist in supporting the overlying geological strata. The coal panels are excavated by the longwall mining system 100, which includes components such as automated electro-hydraulic roof supports, a coal shearing machine (i.e., a longwall shearer), and an armored face conveyor (i.e., AFC) parallel to the coal face. As the shearer travels the width of the coal face, removing a layer of coal (e.g., a web of coal), the roof supports automatically advance to support the roof of the newly exposed section of strata. The AFC is then advanced by the roof supports toward the coal face by a distance equal to the depth of the coal layer previously removed by the shearer. Advancing the AFC toward the coal face in such a manner allows the shearer to engage with the coal face and continue shearing coal away from the coal face.
The health monitoring system 700 monitors shearer position data of the longwall mining system 100 to ensure that the longwall mining system 100 does not experience a loss of horizon. Controlling the horizon in a longwall mining system allows a more efficient extraction of coal by extracting a maximum amount of coal without weakening support for overlying geological strata. For example, loss of horizon in the longwall mining system 100 can cause a degradation of coal quality (e.g., when other non-coal material is being extracted along with coal), deterioration of face alignment, formation of cavities by compromising overlying seam strata, and in some instances, loss of horizon may cause damage to the longwall mining system 100 (e.g., if a roof support canopy collides with a shearer). In some embodiments, the health monitoring system 700 monitors roof support data, AFC data, and other longwall mining system data, additionally or alternatively to the shearer position data.
The system 100 also includes a beam stage loader (BSL) 125 arranged perpendicularly at the maingate end of the AFC 115.
The shearer 110 also includes various sensors, to enable automatic control of the shearer 110. For example, the shearer 110 includes a left ranging arm inclinometer 260, a right ranging arm inclinometer 265, left haulage gear sensors 270, right haulage gear sensors 275, and a pitch angle and roll angle sensor 280.
As coal is sheared away from the coal face 303, the geological strata overlying the excavated regions are allowed to collapse behind the mining system 100 as the mining system 100 advances through the coal seam.
Cavity formation can be caused by a loss of horizon. The loss of horizon refers to an instance in which alignment and/or position of the longwall mining system 100, including the shearer 110, AFC 115, and the roof support 105, deviates significantly from the true topography of the coal seam (e.g., when the left and right cutter drums 240, 235 cut outside the coal seam roof and floor boundaries). When this occurs the mining system 100 does not extract coal in an efficient manner. For example, the shearer 110 may not be properly aligned with the coal seam and therefore, extract non-coal material causing the quality of coal to degrade. Loss of horizon can also introduce unnecessary articulation in the AFC 115 and roof supports 105, which may result in equipment damage and increased wear, and may restrict the roof supports 105 from providing sufficient strata control. The health monitoring system 700 receives information from the various sensors 260, 265, 270, 275, 280 included in the shearer 110 to monitor the alignment and position of the shearer 110 and the cutter drums 235, 240. The health monitoring system 700 generates a pan-line, a floor cut, and a roof cut profile including information regarding the angular position (i.e., pitch and roll) of the shearer 110, which is then used to predict a possible loss of horizon and generates alerts when a possible loss of horizon is predicted.
Thus, outputs of the remote monitoring system 720 can include alerts (events) or other warnings pertinent to specific components of the longwall mining system 100, based on the control logic executed by the system 720. These warnings can be sent to designated participants (e.g., via email, SMS messaging, internet, or intranet based dashboard interface, etc.), such as service personnel at a service center 725 with which the monitoring system 720 is in communication, and personnel underground or above ground at the mine site of the underground longwall control systems 705. It should be noted that the remote monitoring system 720 can also output, based on the control logic executed, information that can be used to compile reports on the mining procedure and the health of involved equipment. Accordingly, some outputs may be communicated with the service center 725, while others may be archived in the monitoring system 720 or communicated with the surface computer 710.
Each of the components in the health monitoring system 700 is communicatively coupled for bi-directional communication. The communication paths between any two components of the system 700 may be wired (e.g., via Ethernet cables or otherwise), wireless (e.g., via a WiFi®, cellular, Bluetooth® protocols), or a combination thereof. Although only an underground longwall mining system and a single network switch is depicted in
The controller 775 can aggregate the shearer position data (e.g., the data collected by the sensors 260, 265, 270, 275, 280) and store the aggregated data in a memory, including a memory dedicated to the controller 775. Periodically, the aggregated data is output as a data file via the network switch 715 to the surface computer 710. From the surface computer 710, the data is communicated to the remote monitoring system 720, where the data is processed and stored according to control logic particular for analyzing data from the shearer control system 750. Generally, the shearer position data file includes the sensor data aggregated since the previous data file was sent. The aggregated shearer position data is also time-stamped based on the time that the sensors 260, 265, 270, 275, 280 obtained the data. The shearer position data can then be organized based on the time it was obtained. For example, a new data file with sensor data may be sent every five minutes, the data file including sensor data aggregated over the previous five minute window. In some embodiments, the time window for aggregating data can correspond to the time required to complete one shear cycle (e.g., time required to extract one web of coal). In some embodiments, the controller 775 does not aggregate sensor data and the remote monitoring system 720 is configured to aggregate the data as it is received in real-time (streamed) from the controller 775. In other words, the remote monitoring system 720 streams and aggregates the data from the controller 775. The remote monitoring system 720 can also be configured to store the aggregated sensor data. The remote monitoring system 720 can then analyze the shearer position data based on stored aggregated data, or based on shearer position data received in real-time from the controller 775.
In the illustrated embodiment, the remote monitoring system 720 analyzes the shearer position data both on a per shear cycle basis and on an instantaneous basis. When the remote monitoring system 720 analyzes the shearer position data on a shear cycle basis, the processor 721 first identifies shearer position data corresponding to a shear cycle, computes horizon profile data based on the raw shearer position data, and then applies specific rules to the horizon profile data within the shear cycle. When the remote monitoring system 720 analyzes the shearer position data on an instantaneous basis, the processor 721 analyzes the shearer position data on an on-going basis by comparing the shearer position data to predetermined operating parameters. This continuous analysis generally does not require first identifying shearer position data corresponding to the same shear cycle. In some embodiments, the analysis of the shearer position data can be implemented locally at the mine site (e.g., on the controller 775).
At step 824, the processor 721 analyzes the horizon profile data to determine whether the pan-line profile, the floor cut profile, and the roof cut profile are within normal operational ranges. Normal operational ranges can refer to, for example, a maximum or minimum pitch angle for the shearer 110, a maximum or minimum height for the floor cut profile, a maximum or minimum height for the roof cut profile, a maximum or minimum extraction (difference between floor and roof cut profiles), a maximum or minimum roll angle for the shearer 110, and the like. At step 826, the processor 721 determines if a position failure has occurred due to the shearer 110, the right cutter drum 235, or the left cutter drum 240 operating outside of the normal operational ranges. For example, a failure occurs when the relative floor cut profile is below a minimum height. If the processor 721 determines that a position failure has not occurred during the shear cycle, the horizon profile data is stored and organized based on the shear cycle (at step 828), and an index number is assigned to the shear cycle (at step 832). In some embodiments, an index number is first assigned to the shear cycle and then the horizon profile data is stored according to the assigned index number, such that it can be readily accessed and analyzed against past or future profile data. If, on the other hand, the processor 721 determines that a position failure has occurred, the processor 721 generates an alert at step 836. Once the alert is generated, the horizon profile data is stored according to the shear cycle (at step 828) and the shear cycle is assigned an index number (at step 832). Again, in some embodiments, the shear cycle is assigned an index number first and then the data is stored according to the index number.
The alert includes information about what components (i.e., the shearer, the right cutter, or the left cutter, or a combination) triggered the alert. The alert can be archived in the remote monitoring system 720 or exported to the service center 725 or elsewhere. For example, the remote monitoring system 720 can archive alerts to later be exported for reporting purposes. The information transmitted by the alert can include identifying information of the particular components, as well as the corresponding time point, the corresponding position of the components, and the corresponding positional bins. The alert can take several forms (e.g., e-mail, SMS messaging, etc.). As discussed above referring to the health monitoring system 700, the alert is communicated to appropriate participants near or remote to the mine.
As also discussed above, the processor 721 identifies a start point and an end point of a shear cycle based on the shearer position data. To identify the start and end of a shear cycle, the processor 721 first determines whether the shearer 110 cuts in a unidirectional manner or in a bidirectional manner. When the shearer 110 cuts in a unidirectional manner, the shearer 110 takes two shearer passes of the coal face to extract one web of coal. When the shearer 110 cuts in a bidirectional manner, the shearer 110 takes one shearer pass of the coal face to extract a web of coal.
In a unidirectional shear cycle, the shearer 110 partially cuts a web of coal while traveling in one direction (e.g., from the tailgate to the maingate) and cuts the remainder of the web when travelling in the reverse direction. In unidirectional operation, the roof supports 105 advance as the shearer 110 passes in one direction and push the AFC 115 as the shearer 110 passes in the opposite direction. In unidirectional operation the shearer 110 and pan-line generally snake into the next web of coal at either the tailgate or maingate ends of the coal face. Unidirectional operation can be configured for forward snake, in which the shearer 110 follows a pan-line snake into the next web as it enters the gate (e.g., maingate or tailgate), or backward snake, where the shearer 110 follows a pan-line snake into the next web as it leaves the gate (e.g., maingate or tailgate).
The roof supports 105 advance as the shearer 110 passes to support the newly exposed strata, but the roof supports 105 do not propel the AFC 115 forward at this point. When the shearer 110 reaches the maingate (point C), the leading cutter drum 240 closest to the maingate lowers to floor level and the cutter drum 235 closest to the tailgate is raised so it is above floor level, but below roof level. The shearer 110 then begins moving back toward the tailgate to cut the lower section of the coal face near the maingate that could not be reached by the cutter drum 235 closest to the tailgate as the shearer 110 entered the maingate. Once the lower section of the coal face is extracted by the cutter drum 240 closest to the maingate, the shearer 110 then continues movement back toward the tailgate cleaning any spilled floor coal. The roof supports 105 push the AFC 115 pans forward as the shearer 110 travels back to the tailgate. As the shearer 110 follows the pan-line into the tailgate it will again enter a forward snake at point D. At point D, the shearer 110 raises the now leading cutter drum 235 (e.g., the cutter drum closest to the tailgate) and starts to cut the next web to begin a new shear cycle. Thus, the start and end of the unidirection shear cycle is marked and identified by the raising of the lead cutter drum 235, 240 as the shearer snakes into next web of coal. In some embodiments, the shearer 110 trams into the tailgate and trams out (e.g., shuffles) before raising the lead cutter drum 235, 240.
In a bidirection shear cycle, the shearer 110 cuts a web of coal both on the pass from the maingate to the tailgate and from the tailgate to the maingate. For example, the shearer 110 takes a complete seam extraction as the shearer 110 cuts from the maingate to the tailgate and another complete seam extraction as the shearer 110 cuts from the tailgate to the maingate. In the bidirectional shear cycle, the roof supports 105 advance and push the AFC 115 after the shearer 110 passes in one direction. In bidirectional operation, the shearer 110 completes a gate-end shuffle when the shearer 110 reaches the opposite gate.
In some embodiments, and as discussed above, the horizon profile and/or the shearer position data is received by the processor 721 in a regular time interval (e.g., every 5 minutes). The time interval, however, does not necessarily align with a single shear cycle. Accordingly, the processor 721 analyzes the shearer position data to identify key points indicative of start and end points of a shear cycle. For instance, the processor 721 identifies one or more of the following key points: turn points of the shearer 110 at both the maingate and the tailgate, changes of direction of the shearer 110 (i.e., shuffle points), and raising of the cutter drums 235, 240 within close proximity to the maingate or to the tailgate. The processor 721 identifies the key points by searching the position data for the shearer 110 for minima and maxima, which correspond to both the gate turn points and the shuffle points. The processor 721 also determines if the cutter drums 235, 240 raise above a predetermined height threshold near the maingate or the tailgate. Once the shear cycle is identified, the processor 721 determines the time region (i.e., a start time and an end time) corresponding to the shear cycle. The processor 721 also determines the start and end points (e.g., a data point indicative of the start of the shear cycle and a data point indicative of the end of the shear cycle) corresponding to the shear cycle.
Once the processor 721 identifies the shear cycle, the processor 721 generates a pan-line profile, a roof cut profile, a floor cut profile, a pitch profile, and an elevation profile associated with the shearer's path through the shear cycle. As discussed above, the shearer 110 travels from the maingate to the tailgate (or vice versa). The shearer 110 supports a right cutter drum 235 and a left cutter drum 240. As the shearer 110 travels in one direction, one of the cutter drums 235, 240 is positioned higher than the other cutter drum such that the height of the coal seam is sheared. In one example, while the shearer 110 travels from the maingate to the tailgate, the right cutter drum 235 is raised and cuts the upper half of the coal face and the left cutter drum 240 cuts the bottom half of the coal face. On the return path, the shearer 110 travels from the tailgate to the maingate, the left and right cutter drums 240, 235 may maintain the same upper and bottom position as on the forward pass or may switch positions.
The pan-line represents the floor plane of the AFC 115 and corresponds to the path followed by the shearer 110 as it traverses the AFC 115. The pan-line is calculated using the angular (e.g., roll and pitch angles) and lateral (e.g., position along the coal face 303 determined using the haulage sensors 270, 275) position measurements of the shearer 110. The roof cut profile corresponds to the position of the cutter drum 235, 240 cutting the upper half of the coal face, and the floor cut profile corresponds to the position of the cutter drum 235, 240 cutting the bottom half of the coal face. The position of the cutter drums 235, 240 to generate the roof cut and floor cut profiles may be calculated based on the center of the cutter drums 235, 240, a top edge of the cutter drums 235 including or excluding the mining bits, a bottom edge of the cutter drums 235, 240 including or excluding the mining bits, or other similar location of the cutter drums 235, 240. Additionally, the position of the cutter drums 235, 240 to generate the floor and roof cut profiles are calculated with reference to the pan-line
To generate the roof cut profile and the floor cut profile, the path of each of the cutter drums 235, 240 is estimated relative to the pan line. The shearer position is added to the relative cutter center's position to convert the relative cutter centers' position into an absolute cutter centers' position relative to the pan-line. Once the cutters' path has been computed, each center position (for the right cutter drum 235 and the left cutter drum 240) is binned within discrete position intervals. In some embodiments, the discrete position intervals correspond to a roof support index as described above, or a group of roof supports (i.e., each position index corresponds to 6 roof supports), or a fraction of a roof support. The roof cut is then computed as the maximum center height within each position bin plus the radius of the cutter drum 235, 240. Similarly, the floor cut is computed as the minimum center height within each position bin minus the radius of the cutter 235, 240. The pitch and elevation profiles are calculated using the average of the pitch data and the roll data, respectively, in each of the position bins.
Once the roof cut profile, the pan-line profile, the floor cut profile, the pitch profile, and the elevation profile have been computed for a given shear cycle, the processor 721 determines whether each of the profiles is within normal operational parameter ranges. An exemplary plot of a shear cycle is shown in
The analysis module 954 analyzes the floor cut profile, the roof cut profile, the pan-line profile, the pitch profile, and the elevation profile in relation to the floor step parameter, the extraction parameter, the pitch parameter, and the roll rate parameter. The floor step parameter refers to a difference between the pan line profile and the floor cut profile. If the floor step exceeds a threshold, the longwall mining system 100 may have an adverse pan pitching response when the system 100 (i.e., the roof supports 105 and the AFC 115) advances. For example, large step changes in the floor profile can lead to sudden changes in pan pitch attitude, which can cause the horizon to quickly deviate off the coal seam. Large step changes can also impact the ability of the roof supports 105 to advance cleanly, which can further impact the ability to control the horizon along the coal face. In some instances, large floor steps can cause the shearer 110 to collide with the canopies 315.
The floor cut profile is divided up into a maingate section (MG), a run-of-face section (ROF), and a tailgate section (TG) based on the pan position of the shearer 110, as illustrated in
The analysis module 954 analyzes the maingate section (MG), the run-of-face section (ROF), and the tailgate section (TG) of the floor cut profile separate from each other. In some embodiments, the analysis module 954 applies different thresholds to each section of the floor cut profile.
For example, in an unfiltered floor cut profile, for the first position bin the floor cut data is 0 meters, for the second position bin the floor cut data is −0.4 meters, for the third position bin the floor cut data is −0.8 meters, for the fourth position bin the floor cut data is −0.85 meters, for the fifth position bin the floor cut data is −0.95 meters, and for the sixth position bin the floor cut data is −0.98 meters. A filtered floor cut profile may group the first and second position bins together to assign a value to a first pan position, group the third and fourth position bins together to assign a value to a second pan position, and group the fifth and sixth position bins together to assign a different value to a third pan position. In one example, an average of the floor cut data of the position bins grouped together for one pan position is used to assign a value to the pan position. In the example above, the first pan position has a value of −0.2 meters, the second pan position has a value of −0.825 meters, and the third pan position has a value of −0.965 meters. A difference between one pan position (e.g., the first pan position) and another pan position (e.g., the third pan position) corresponds to a pan length (e.g., 2 pan positions). Thus, filtering the floor cut profile data can reduce the amount of data analyzed by the analysis module 954 and may, in some instances, make the analysis faster and more efficient. In some embodiments, the filtering process does not calculate an average. Rather, in some embodiments, the filtering process assigns the highest value to the filtered position bins, the lowest value, or the median value of the filtered position bins. In some embodiments, the window filter is higher than two position bins.
At step 842, the analysis module 954 identifies floor cut profile data corresponding to a predetermined pan length for the associated parameter (e.g., the floor step parameter). The predetermined pan length indicates the minimum number of consecutive pan positions for which the floor step parameter operates outside of the normal operational range for the alert module 958 to generate an alert. In the illustrated embodiment, the predetermined pan length for the floor cut parameter is three pan positions. The analysis module 954 determines if a parameter operates within or outside of normal operational ranges by determining if a parameter (e.g., the floor step parameter) is below or above a particular operational threshold for a predetermined pan length. If, for example, the parameter exceeds the particular operational threshold (e.g., the floor step threshold) for less than the predetermined pan length (e.g., for one pan position instead of 3 pan positions), the analysis module 954 determines that the parameter (e.g., the floor step parameter) still operates within the normal operational range. In other words, the analysis module 954 determines if 3 or more consecutive data points of the filtered floor cut profile exceed a floor step threshold. While describing how the analysis module 954 analyzes the horizon profile data with regard to the other parameters (e.g., the roof cut parameter, the pitch parameter, the extraction parameter, and the like), the analysis module 954 determines whether a particular parameter exceeds or is below a threshold for a predetermined pan length. It should be understood that in some embodiments, the analysis module 954 determines that the particular parameter is outside the normal operational range for the pan length only when the predetermined number of consecutive data points all exceed (or are below) the threshold.
In other embodiments, the predetermined pan length is less or more than three consecutive pan positions. In some embodiments the predetermined pan length changes based on the parameter. For example, the floor cut parameter may have a predetermined pan length of three consecutive pan positions while the extraction parameter may have a predetermined pan length of five consecutive pan positions.
At step 844, the analysis module 954 identifies the appropriate floor step threshold and the appropriate undercut threshold to be used for the identified predetermined pan length. The appropriate floor step threshold and undercut threshold can be based on, for example, which section of data the predetermined pan length corresponds to. For example, if the floor cut data in the predetermined pan length corresponds to the maingate section of the floor cut profile, the analysis module 954 may use a maingate floor step threshold and a maingate undercut threshold. If, however, the floor cut data in the predetermined pan length corresponds to the run-of-face section of the floor cut profile, the analysis module 954 may use a run-of-face floor step threshold and a run-of-face undercut threshold. Similarly, if the floor cut data for the predetermined pan length corresponds to the tailgate section of the floor cut profile, the analysis module 954 may use a tailgate floor step threshold and a tailgate undercut threshold.
At step 846, the analysis module 954 determines if the floor cut data is greater than the appropriate floor step threshold (e.g., 0.2 meters) for the predetermined pan length (e.g., three pan positions). If the analysis module 954 determines that the floor cut data in the predetermined pan length is greater than the floor step threshold, the analysis module 954 determines that the floor step parameter operates outside a normal operational range for that predetermined pan length (step 848) and sets a flag associated with the predetermined pan length (step 850). The flag indicates that a position failure associated with the floor step parameter was determined for the identified pan length. Once the flag is set, the analysis module 954 proceeds to step 852. If, on the other hand, the analysis module 954 determines that the floor cut data in the predetermined pan length is not greater than the floor step threshold, the analysis module 954 determines that the floor cut data for the identified pan length operates within normal operating range and continues to analyze the floor cut data in relation to the undercut threshold.
At step 852, the analysis module 954 determines if the floor cut data in the predetermined pan length is less than the appropriate undercut threshold (e.g., −0.3 meters). If the analysis module 954 determines that the floor cut data in the predetermined pan length is less than the undercut threshold, the analysis module 954 determines that the floor step parameter operates outside the normal operational range for the predetermined pan length (step 854) and sets a flag associated with the predetermined pan length (step 856). The flag, as mentioned above, indicates that a position failure associated with the floor step parameter was determined for the identified pan length. Once the flag is set, the analysis module 954 determines if the end of file (i.e., the end of the horizon profile data for the shear cycle) is reached (step 858). If, on the other hand, the analysis module 954 determines that the floor cut data in the predetermined pan length is not less than the undercut threshold, the analysis module 954 determines that the floor cut data is within normal operational range for the identified pan length and then determines if the end of file has been reached (step 858).
If the end of file is not yet reached, the analysis module 954 proceeds to step 842 to identify floor cut data for another predetermined pan length. For example, if at first the analysis module 954 analyzes floor cut data corresponding to a pan length including pan positions 1, 2, and 3, when the analysis module 954 determines that the end of file is not yet reached, the analysis module 954 identifies floor cut data corresponding to, for example, pan positions 2, 3, 4, since pan positions 2, 3, and 4 correspond to the next set of three consecutive pan positions. When the end of file is reached, the analysis module 954 determines if any flags have been set for the floor cut profile data of the shear cycle (step 860). If the analysis module 954 determines that flags were set while analyzing floor cut data for the shear cycle, the alert module 958 generates an alert as described above (step 862). If, on the other hand, the analysis module 954 determines that flags were not set while analyzing floor cut profile data for the shear cycle, the analysis module 954 determines that the floor cut parameter operates in the normal operational range during the shear cycle and no alert is generated (step 864).
At step 874, the analysis module 954 determines whether the extraction data for the predetermined pan length is greater than the appropriate maximum extraction threshold (e.g., 4.8 meters). If the extraction data for the pan length is greater than the appropriate maximum extraction threshold, the analysis module 954 determines that the extraction parameter operates outside the normal operational range (step 876) and sets a flag associated with the identified pan length (step 878). The flag indicates that a position failure associated with the extraction parameter was determined for the identified pan length. Once the flag is set, the analysis module 954 determines if the end of file (i.e., the end of the horizon profile data for the shear cycle) has been reached (step 880). If, on the other hand, the extraction data for the identified pan length is not greater than the appropriate maximum extraction threshold, the analysis module 954 goes to step 880 to determine if the end of file has been reached.
If the end of file is not yet reached, the analysis module 954 proceeds to step 870 to identify extraction data corresponding to another predetermined pan length as described above with reference to step 842. When the end of file is reached, the analysis module 954 determines if any flags have been set for the extraction data for the shear cycle, at step 882. If the analysis module 954 determines that flags were set while analyzing extraction data for the shear cycle, the alert module 958 generates an alert (step 884). If the analysis module 954 determines that flags were not set while analyzing the extraction data for the shear cycle, the analysis module 954 determines that the extraction parameter operates in the normal operational range during the shear cycle and no alert is generated (step 886).
At step 891, the analysis module 954 determines if the pan pitch data for the pan length is greater than a maximum pan pitch threshold (e.g., 6.0 degrees). If the pan pitch data for the pan length is greater than the appropriate maximum pan pitch threshold, the analysis module 954 determines that the pan pitch operates outside of the normal operational range (step 892) and sets a flag associated with the pan length (step 893). The flag indicates that a position failure associated with the pan pitch was determined at the identified pan length for the shear cycle. Once the flag is set, the analysis module 954 analyzes the pan pitch data according to the appropriate minimum pan pitch threshold (step 894). If, on the other hand, the pan pitch data for the pan length is not greater than the appropriate maximum pan pitch threshold, the analysis module 954 proceeds directly to step 894.
At step 894, the analysis module 954 determines if the pan pitch data for the identified pan length is below the appropriate minimum pan pitch threshold (e.g., −6.0 degrees). If the pan pitch data for the pan length is below the minimum pan pitch threshold, the analysis module 954 determines that the pan pitch parameter operates outside the normal operational range (step 895) and sets a flag associated with the pan length (step 896). The flag, as discussed above, indicates that a position failure associated with the pan pitch was determined at the identified pan length for the shear cycle. Once the flag is set, the analysis module 954 determines if the end of file (i.e., the end of the horizon profile data for the shear cycle) has been reached (step 897). If the pan pitch data for the pan length is not below the appropriate minimum pan pitch threshold, the analysis module 954 proceeds directly to step 897 to determine if the end of file has been reached.
If the end of file has not been reached, the analysis module 954 goes back to step 889 to identify another pan length and continue analyzing the pan pitch data for the shear cycle. When the end of file is reached, the analysis module 954 determines if any flags have been set (step 898). If flags have been set, the alert module 958 generates an alert (step 899). If flags have not been set, the analysis module 954 determines that the pan pitch parameter operates within the normal operational range and no alert is generated (step 900).
At step 905, the analysis module 954 determines if the pan roll rate data for the predetermined pan length is greater than the appropriate maximum pan roll rate threshold (e.g., 0.5 degrees per pan length). If the pan roll rate data for the pan length is greater than the appropriate maximum pan roll rate threshold, the analysis module 954 determines that the pan roll parameter operates outside the normal operational range (step 906) and sets a flag associated with the identified pan length (step 907). The flag indicates that a position failure associated with the pan roll rate was determined for the shear cycle. Once the flag is set, the analysis module 954 continues analyzing the pan roll rate data and proceeds to step 908. If, on the other hand, the pan roll rate data for the pan length is not greater than the appropriate maximum pan roll rate threshold, the analysis module 954 goes directly to step 908 to determine if the pan roll rate data for the pan length is below the appropriate minimum pan roll rate threshold (e.g., −0.5 degrees per pan length). If the pan roll rate data for the identified pan length is below the minimum pan roll rate threshold, the analysis module 954 determines that the pan roll parameter operates outside the normal operational range (step 909) and generates a flag associated with the pan length (step 910). The flag indicates that a position failure associated with the pan roll rate was determined for the shear cycle. Once the flag is set, the analysis module 954 determines if the end of file (i.e., the end of the horizon profile data for the shear cycle) is reached at step 911. If, on the other hand, the pan roll rate data for the identified pan length is not below the minimum pan roll threshold, the analysis module 954 proceeds directly to step 911. If the end of file has not been reached, the analysis module 954 goes back to step 903 to identify pan roll rate data for a new pan length of three. When the end of file is reached, the analysis module 954 determines if any flags have been set during the shear cycle, at step 912. If flags have been set, the alert module 958 generates an alert at step 913. If no flags have been set, the analysis module 954 determines that the pan roll parameter operates within the normal operating range (step 914).
Once the analysis module 954 analyzes the shear cycle with respect to the floor step parameter, the extraction parameter, the pitch parameter, and the roll rate parameter, the horizon profile data for the shear cycle is stored in a database for later access. As described in
It should also be understood that while a specific order was described for monitoring each parameter, the analysis module 954 may monitor the parameters in any given order. It should also be understood that although the floor cut profile, the roof cut profile, the extraction profile, the pan roll rate profile, and the pan pitch profile were described as being filtered, in some embodiments, the horizon profile data is not filtered and the entire data is used to analyze the horizon data with respect to a specific parameter. It should also be understood that while the floor cut profile, the roof cut profile, the extraction profile, the pan roll rate profile, and the pan pitch profile were described as being analyzed separately by a maingate section, a run-of-face section, and a tailgate section, the horizon profile data may be sectioned in a different manner, or not sectioned at all. In such embodiments, the horizon profile data is analyzed as a whole and the step of identifying appropriate thresholds may be bypassed by the analysis module 954.
The analysis module 954 also determines if the floor cut profile, the roof cut profile, the pan pitch profile, and the pan roll profile deviate significantly between two shear cycles. For example, since the horizon profile data for each shear cycle is stored in a database, the analysis module 954 can compare the horizon profile data from a previous shear cycle to the horizon profile data from a current shear cycle and determine if the difference in horizon profile data is significant. The analysis module 954 determines if a deviation in the floor cut profile between two shear cycles, or if a deviation in the roof cut profile between two shear cycles is significant. In the illustrated embodiment, the analysis module 954 analyzes two consecutive shear cycles. Generally, when the shearer 110 remains aligned with the coal face, the deviation in roof cut profile and floor cut profile between two consecutive cycles is relatively small. The analysis module 954 can also determine if consecutive changes in the pan pitch and the pan roll profiles (or pan roll rate profiles) are generally trending toward a warning level (e.g., a high pitch warning level, a low pitch warning level, a high roll warning level, or a low roll warning level). Excessive pan pitching or pan rolling may cause loss of horizon, and in extreme cases, the canopies 315 may collide with the shearer 110.
If the floor profile difference for the pan length is greater than the consecutive floor step threshold (e.g., 0.3 meters), the analysis module 954 determines that the deviation in floor cut profiles between the two shear cycles is significant (step 1008) and sets a flag associated with the associated pan length (step 1010). The flag indicates that the deviation of the floor cut profile between the current shear cycle and the previous shear cycle is significant. Once the flag has been set, the analysis module 954 proceeds to step 1012. Similarly, if the analysis module 954 determines that the floor profile difference for the pan length is not greater than the maximum consecutive floor step threshold, the analysis module 954 proceeds to analyze the floor cut profile difference with respect to the consecutive undercut threshold (step 1012).
At step 1012, the analysis module 954 determines if the floor cut profile difference for the pan length is below the minimum consecutive undercut threshold (e.g., −0.3 meters). If the floor cut profile difference is below the minimum consecutive undercut threshold, the analysis module 954 determines that the deviation in floor cut profiles is significant (step 1014) and sets a flag associated with the pan length (step 1016). The flag, as described above, indicates that the deviation in floor cut profiles for the shear cycle is significant. Once the flag is set, the analysis module 954 determines if the end of file (i.e., the end of the horizon profile data for the shear cycle) has been reached (step 1018). Similarly, if the floor profile difference is not below the minimum consecutive undercut threshold, the analysis module 954 determines if the end of file has been reached (step 1018). If the end of file has not yet been reached, the analysis module 954 proceeds to step 1002 to identify the floor profile difference data for another pan length. When the end of file is reached, the analysis module 954 determines if any flags have been set (step 1020). If flags have been set during the shear cycles, the alert module 958 generates an alert (step 1022). If no flags were set, the analysis module 954 determines that the deviation in floor cut profiles between the previous shear cycle and the current shear cycle is not significant (step 1013).
In some embodiments, the deviation between the floor cut profile of a current shear cycle and the floor cut profile of a previous shear cycle can be analyzed separately for each section of the floor cut profile. For example, the analysis module 954 can first compare the difference between the two floor cut profiles to a maingate maximum consecutive floor step threshold and to a maingate minimum consecutive undercut threshold. The analysis module 954 can then compare the difference between the two floor cut profiles to a run-of-face consecutive floor step threshold and a run-of-face consecutive undercut threshold, and finally the analysis module 954 can compare the difference between the two floor cut profiles to a tailgate floor step threshold and a tailgate undercut threshold. The order in which the analysis module 954 compares the sections of the two floor cut profiles may vary.
The analysis module 954 also determines if the deviation between the roof cut profile of the current shear cycle and the roof cut profile of the previous shear cycle is significant, as shown in
The analysis module 954 then determines if the roof profile difference for the pan length is greater than a maximum consecutive roof step threshold (e.g., 0.2 meters) at step 1032. If the roof cut difference profile data is greater than the maximum consecutive roof step threshold, the analysis module 954 determines that the deviation in roof cut profiles between the current shear cycle and the previous shear cycle is significant (step 1034), and a flag is set that is associated with the analyzed pan length (step 1036). The flag indicates that the deviation of the roof cut profile between the current shear cycle and the previous shear cycle is significant. Once the flag is set, the analysis module 954 determines if the roof cut difference profile is below the minimum consecutive roof undercut threshold (e.g., −0.4 meters) at step 1038. If, however, the roof difference profile data is not greater than the maximum consecutive roof step threshold, the analysis module 954 proceeds directly to step 1038.
If the roof profile difference data for the pan length is below the minimum consecutive roof undercut threshold, the analysis module 954 determines that the deviation in roof cut profiles between the current shear cycle and the previous shear cycle is significant (step 1040) and sets a flag associated with the pan length indicating that the deviation in roof cut profiles between the two shear cycles is significant (step 1042). Once the flag is set, the analysis module 954 determines if all the roof difference profile data has been analyzed (step 1044). If the roof difference profile data is not below the minimum consecutive roof undercut threshold, the analysis module 954 determines if the end of file (i.e., the end of the roof difference profile data for the shear cycles) has been reached (step 1044). If the end of file has not been reached yet, the analysis module 954 proceeds to step 1030 to identify a different pan length and continue analyzing the roof difference profile data. When the end of file is reached and all the roof difference profile data for the two shear cycles has been analyzed, the analysis module 954 determines if any flags were set (step 1046). If flags were set, the alert module 958 generates an alert at step 1048. If flags were not set, the analysis module 954 determines that the deviation in roof cut profiles between the current shear cycle and the previous shear cycle is not significant, step 1049.
The analysis module 954 also determines if over-extraction occurs in the same region on consecutive shear cycles, as shown in
The analysis module 954 also determines if the shearer 110 is trending toward a high pitch warning level, a low pitch warning level, a high roll warning level, or a low roll warning level. Reaching the pitch and/or roll warning levels may be indicative of a position failure and may, in some situations, cause the shearer 110 to lose horizon. The high pitch warning level may be a maximum positive pitch level (e.g., 5 degrees) and the low pitch warning level may be a maximum negative pitch level (e.g., −5 degrees). Similarly, the high roll warning level may be a maximum positive roll rate change level (e.g., 0.25 degrees per pan length) and the low roll warning level may be a maximum negative roll rate change (e.g., −0.25 degrees per pan length).
As shown in
The analysis module 954 may determine that the pan-line is approaching a pitch warning level or a roll warning level by, for example, determining the change in pan pitch and/or roll for more than two consecutive shear cycles. If, for example, the pan-line has a positive pitch change on consecutive shear cycles, the analysis module 954 may determine that the pan-line is trending toward the high pitch warning level. If, on the other hand, the pan-line experiences a positive pitch change and a negative pitch change, the analysis module 954 determines that the pan-line is not trending toward a high pitch warning level. If the pan-line experiences two consecutive negative pitch changes, the analysis module 954 may determine that the pan-line is trending toward the low pitch warning level. A similar procedure may be followed to determine if the pan-line is trending toward a roll warning level (e.g., the high roll warning level or a low roll warning level). If across two consecutive shear cycles the pan-line experiences two consecutive positive roll rate changes, the analysis module 954 may determine that the pan-line is approaching the high roll warning level. If, on the other hand, the pan-line experiences two consecutive negative roll changes, the analysis module 954 may determine that the pan-line is approaching the low roll warning level. If the pan-line experiences a positive roll change followed a negative roll change, the analysis module 954 may determine that the pan-line is not trending toward a roll warning level.
The analysis module 954 may additionally or alternatively determine that the pan-line is trending toward a pitch warning level by first identifying a predetermined pan length (e.g., three pan positions) for the pan pitch data of the current shear cycle and the previous shear cycle and determining if the pitch of the pan-line of the current shear cycle for the predetermined pan length is above a high pitch monitoring threshold (e.g., 4 degrees) or is below a low pitch monitoring threshold (e.g., −4 degrees). If the pitch of the pan-line of the current shear cycle is above the high pitch monitoring threshold for the predetermined pan length or below the low pitch monitoring threshold for the predetermined pan length, then the analysis module 954 calculates a difference between the pan pitch profile of the current shear cycle and the pan pitch profile of the previous shear cycle. The analysis module 954 then identifies the predetermined pan length for the pan pitch difference profile data and determines whether the pan pitch difference for the predetermined pan length is above a maximum pitch deviation threshold (e.g., 2 degrees) or is below a minimum pitch deviation threshold (e.g., −2 degrees). If the pan pitch difference for the predetermined pan length is greater than the maximum pitch deviation threshold, the analysis module 954 determines that the pitch of the shearer 110 is trending toward the high pitch warning level. If the pan pitch difference for the predetermined pan length is less than the minimum pitch deviation threshold, the analysis module 954 determines that the pitch of the shearer 110 is trending toward a low pitch warning level.
A similar procedure may be followed to determine if the pan roll rate is trending toward a high roll warning level or a low roll warning level. For example, the analysis module 954 may first identify a predetermined pan length (e.g., three pan positions) for the pan roll rate data of the current shear cycle and the previous shear cycle. The analysis module 954 then determines if the pan roll rate of the current shear cycle exceeds a high roll monitoring threshold or is below a low roll monitoring threshold for the predetermined pan length. If the pan roll of the shearer 110 during the current shear cycle for the predetermined pan length exceeds the high roll monitoring threshold or is below the low roll monitoring threshold, the analysis module 954 then determines if the deviation in pan roll rate between the current shear cycle and the previous shear cycle exceeds appropriate thresholds. For example, the analysis module 954 may calculate a difference of the pan roll rate data of the current shear cycle and the pan roll rate data of the previous shear cycle. The analysis module 954 then identifies the predetermined pan length for the pan roll rate difference data and determines whether the pan roll rate difference data for the predetermined pan length is above a maximum roll rate deviation threshold (e.g., 0.25 degrees per pan) or is below a minimum roll rate deviation threshold (e.g., −0.25 degrees per pan). If the pan roll rate difference data exceeds the maximum roll rate deviation threshold, the analysis module 954 determines that the pan roll is trending toward the high roll warning level. If the roll rate difference data is below the minimum roll rate deviation threshold, the analysis module 954 determines that the pan-line is trending toward the low roll warning level.
As explained above with reference to the pan pitch data and the pan roll data, the analysis module 954 may first determine if the pan roll data and/or the pan pitch data is above or below a monitoring threshold. Comparing the pan roll/pan pitch data to a monitoring data allows the analysis module 954 to focus on pan roll and pan pitch changes that may actually indicate that the pan-line is trending toward a pan roll or pan pitch warning level. For example, changes in pan pitch or pan roll when the pan roll/pan pitch data is below the high monitoring threshold and above the low monitoring threshold may not indicate that the shearer 110 is trending toward a pan roll or pan pitch warning level, and thus can be ignored by the analysis module 954. For example, if the pan pitch data for a predetermined pan length is −4 degrees in the previous shear cycle and 2 degrees in the current shear cycle, the analysis module 954 may ignore the high (6 degree) positive change because the pan pitch data for the predetermined pan length, −4 degrees, is not above the high pitch monitoring threshold (e.g., 12 degrees) or below the low pitch monitoring threshold (e.g., −12 degrees). The high positive change is ignored even if the deviation between the pan pitch data for the previous shear cycle and the pan pitch data for current shear cycle exceeds the high pan pitch deviation threshold (e.g., 5 degrees).
Nonetheless, in some embodiments, the analysis module 954 calculates the difference between the pan pitch profile of the current shear cycle and the pan pitch profile of the previous shear cycle or the difference between the roll rate profile of the current shear cycle and the roll rate profile of the previous cycle, without comparing the pan pitch data or the roll rate data of the current shear cycle to a monitoring threshold first. The analysis module 954 may then identify a predetermined pan length of the pan pitch and/or roll rate difference profile and determine where the pan pitch difference profile or the pan roll rate difference profile exceeds the maximum pitch deviation threshold (e.g., 2 degrees) or is below the minimum pitch deviation threshold (e.g., −2 degrees) for the predetermined pan length.
The analysis module 954 is also configured to analyze instantaneous shearer data. Instantaneous shearer data includes a stream of shearer data not necessarily segmented into data blocks corresponding to individual shear cycles. For instance, some analysis techniques discussed above include receiving shearer data, identifying a shear cycle start and end points, then analyzing the data associated with the particular shear cycle for position failures. In contrast, analysis of instantaneous shearer data is generally independent of shear cycle boundaries. Additionally, the analysis may occur in real-time. The analysis module 954 analyzes instantaneous horizon control data to determine if the roof cut is above a high roof cut threshold, if the floor cut is below a low floor cut threshold, and if the shearer pitch angle in above or below a pitch angle threshold.
The analysis module 954 then determines if cutting picks 245 of either cutter drum 235 or 240) are below a low floor cut threshold for more than a second pan length (e.g., 5 pan positions) at step 2012. If the cutting picks 245 of either cutter drum 235, 240 are below the low floor cut threshold for further than the second pan length, the alert module 958 generates an alert message at step 2014 and the analysis module 954 proceeds to step 2016. If the cutting picks 245 of either cutter drum 235, 240 are not below the low floor cut threshold for further than the second pan length (e.g., are below the low floor cut threshold for less than the second pan length or are not below the low floor cut threshold at all), the analysis module 954 proceeds directly to step 2016.
The analysis module 954 also determines if the pitch of the shearer 110 exceeds a high pitch threshold (e.g., 6 degrees) for further than a third pan length at step 2016. If the pitch of the shearer 110 exceeds the high pitch threshold, the alert module 958 generates an alert at step 2018 and the analysis module 954 then proceeds to step 2020. If the pitch of the shearer 110 does not exceed the high pitch threshold, the analysis module 954 proceeds directly to step 2020. The analysis module 954 also determines if the pitch of the shearer 110 is below a low pitch threshold (e.g., −6 degrees) for further than a fourth pan length at step 20240. If the analysis module 954 determines that the pitch of the shearer 110 remains below the low pitch threshold for further than the fifth predetermined pan length, the alert module 958 generates the alert at step 2026. If the pitch of the shearer 110 is not below the low pitch threshold, the analysis module 954 goes back to step 2006 and continues to monitor the instantaneous shearer data. One or more of the first, second, third, fourth, and fifth predetermined pan lengths may be the same (e.g., 5 pan positions) or different depending on the parameter being analyzed.
In some embodiments, the analysis module 954 checks each of the above conditions for each set of shearer data that the analysis module 954 receives. Similarly, although the steps in
The alert generated by the alert module 958 when instantaneous shearer data is analyzed is presented to a participant.
The e-mail alert 3000 also includes an attached image file 3004. In the illustrated embodiment, the attached image file 3004 is a Portable Network Graphic (.png) file, including a graphic depiction to assist illustration of the event or scenario causing the alert. For example, when the analysis module 954 identifies the shear cycle before analyzing the horizon data, the attached image file 3004 can include an image similar to
In some instances, a generated alert takes another form or includes further features. For example, an alert generated by the alert module 958 can also include an instruction sent to one or more components of the longwall mining system 100 (e.g., to the longwall shearer 110) to safely shut down.
Additionally, alerts generated by the alert module 958 can have different priority levels depending on the particular alert (e.g., depending on which parameters triggered the alert). Generally, the higher the priority the more severe the alert. For example, a high priority alert can include automatic instructions to shut down the entire longwall mining system 100 while a low priority alert may just be included in a daily report log.
It should be noted that one or more of the steps and processes described herein can be carried out simultaneously, as well as in various different orders, and are not limited by the particular arrangement of steps or elements described herein. In some embodiments, the health monitoring system 700 can be used by various longwall mining-specific systems, as well as by various other industrial systems not necessarily particular to longwall or underground mining.
It should be noted that as the remote monitoring system 720 runs the analyses described with respect to
Thus, the invention provides, among other things, systems and methods for monitoring a longwall shearing mining machine in a longwall mining system. Various features and advantages of the invention are set forth in the following claims.
The present application claims priority to U.S. Provisional Patent Application No. 62/043,387 and is related to co-filed U.S. patent application Ser. No. 14/839,581, the entire contents of both of which are incorporated herein by reference.
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