Abstract:
Disclosed is a system to evaluate and monitor the status of a material forming part of an asset, such as a refractory furnace. The system is operative to identify flaws and measure the erosion profile and thickness of different materials, including refractory materials of an industrial furnace, using radiofrequency signals. The system is designed to integrate software with a plurality of sensors and additional hardware to collect data during an inspection of the furnace, even in regions of difficult access. Furthermore, the system comprises a software management subsystem configured to implement signal processing techniques to process the data collected and generate reports to visualize the status, estimate the remaining operational life, and determine the level of penetration of molten material into the surrounding layers of the furnace. Moreover, the system&#39;s software enables a user to monitor the status of the furnace both locally and remotely.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based upon and claims priority from co-pending U.S. Provisional Patent Application Ser. No. 62/247,869 entitled “ASSET LIFE OPTIMIZATION AND MONITORING SYSTEM” filed with the U.S. Patent and Trademark Office on Oct. 29, 2015, by the inventors herein, the specification of which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to systems for evaluating the status of a material. More particularly, the present invention relates to systems for monitoring and determining the condition of refractory material using radiofrequency signals. 
       BACKGROUND OF THE INVENTION 
       [0003]    A number of evaluation and monitoring systems have been disclosed within various industries for measuring the properties during and after formation of certain materials, using radiofrequency signals. The surface characteristics, internal homogeneity, thickness, and rate of erosion of a material are some of the important attributes that may require monitoring and evaluation. 
         [0004]    On a bigger scale, some industries such as the glass, steel, and plastic industries use large furnaces to melt the raw material used for processing. These furnaces may reach a length equivalent to the height of a 20-story building. Thus, they are a key asset for manufacturers in terms of costs and operational functionality. In order to minimize the internal heat loss at high operating temperatures, these furnaces are constructed using refractory material, having very high melting temperatures and good insulation properties, to create a refractory melting chamber. However, the inner walls of the refractory chamber of the furnace will degrade during operation. The effects of this degradation include inner surface erosion, stress cracks, and refractory material diffusion into the molten material. 
         [0005]    In particular, the use of microwave signals to measure the thickness of materials such as furnace walls have been addressed in the prior art, as described in U.S. Pat. No. 6,198,293 to Woskov et al. and U.S. Pat. No. 9,255,794 to Walton et al., the specifications of which are incorporated herein by reference in their entireties. However, these efforts have faced certain challenges and limitations. In particular, attempts made to determine furnace wall thickness on hot furnaces have been generally unsuccessful because of the large signal losses involved in evaluating the inner surface of refractory materials, especially at relatively high frequency bands. Likewise, at relatively low frequency bands signals still experience losses and are limited in terms of the bandwidth and resolution required by existing systems. 
         [0006]    Moreover, in placing system components close to the surface of the refractory material to be evaluated, spurious signal reflections make it difficult to isolate the reflected signal of interest, thus further complicating the evaluation of the status of either the inner surface or the interior of such materials. A major challenge is that furnace walls become more electrically conductive as temperature increases. Therefore, signals going through a hot furnace wall experience significant losses making the detection of these signals very challenging. 
         [0007]    Additional efforts have been made to evaluate the status of a material, using electromagnetic waves, by reducing the losses and level of spurious signals involved in evaluating refractory materials, as described in U.S. Pat. App. No. 20150362439 by Bayram et al. and U.S. Pat. App. No. 20150276577 by Ruege et al., the specifications of which are incorporated herein by reference in their entireties. However, these systems are primarily aimed to mitigate multiple reflection effects of the electromagnetic waves used for suppression of clutter associated with the received signal. In addition, these attempts have focused on standalone systems lacking integration as a single solution, further requiring software for maximizing the extraction of information from the measured data, and facing challenges to access areas of difficult access in an industrial environment. As a result, these systems are not able to monitor and evaluate a large asset, such as an industrial furnace, for optimizing its operational life, without the support of tracking and software tools. 
         [0008]    Currently, there is no well-established integrated system of deterministically and effectively measuring the rate of penetration of molten material into the surrounding refractory material to optimize both the operational life and the maintenance plan of the furnace. As a result, manufacturers experience either an unexpected leakage of molten material through the furnace wall or conservatively shut down the furnace for re-build to reduce the likelihood of any potential leakage, based on the manufacturer&#39;s experience of the expected lifetime of the furnace. The lifetime of a furnace is affected by a number of factors, including the operational age, the average temperature of operation, the heating and cooling temperature rates, the range of temperatures of operation, the number of cycles of operation, and the type and quality of the refractory material as well as the load and type of the molten material used in the furnace. Each of these factors is subject to uncertainties that make it difficult to create accurate estimates of the expected lifetime of a furnace. 
         [0009]    Moreover, the flow of molten material, such as molten glass, at high temperatures erodes and degrades the inner surface of the refractory material and creates a high risk for molten glass leakage through the refractory wall. A major leak of molten glass through the gaps and cracks in the furnace walls may require at least 30 days of production disruption before the furnace can be restored to operating mode because it needs to be cooled down, repaired, and fired up again. Furthermore, a leak of molten glass may cause significant damage to the equipment around the furnace and, most importantly, put at risk the health and life of workers. For these reasons, in most cases furnace overhauls are conducted at a substantially earlier time than needed. This leads to significant costs for manufacturers in terms of their initial investment and the reduced production capacity over the operational life of the furnace. 
         [0010]    Another important issue is that the material used to build the refractory chamber of the furnace may have internal flaws not visible by surface inspection. This could translate into a shorter life of the furnace and pose serious risks during furnace operation. Accordingly, on the one hand the refractory material manufacturer would like to have a means to evaluate the material during manufacture to be able to qualify the material for furnace construction following quality standards to deliver material with no flaws. On the other hand, the customer purchasing the refractory material would like to have a means for performing internal inspections of such material before constructing a furnace. Thus, there remains a need in the art for systems capable of remotely evaluating the status of such refractory materials, through measurements of propagating radiofrequency signals that avoid the problems of prior art systems. 
       SUMMARY OF THE INVENTION 
       [0011]    An improved system to evaluate and monitor the status of a material forming part of an asset, such as a refractory furnace, is disclosed herein. One or more aspects of exemplary embodiments provide advantages while avoiding disadvantages of the prior art. The system is operative to identify flaws and measure the erosion profile and thickness of different materials, including (by way of non-limiting example) refractory materials of an industrial furnace, using radiofrequency signals. The system is designed to integrate software with a plurality of sensors and additional hardware to collect data during an inspection of the furnace, even in regions of difficult access. Furthermore, the system comprises a software management subsystem configured to implement signal processing techniques to process the data collected and generate reports to visualize the status, estimate the remaining operational life, and determine and report the level of penetration of molten material into the surrounding layers of the furnace. Moreover, the system&#39;s software enables a user to monitor the status of the furnace both locally and remotely. 
         [0012]    The system transmits a radiofrequency signal into a surface of a material to be evaluated by an antenna disposed contiguous to that surface. The radiofrequency signal penetrates the material and reflects from remote discontinuities. Any voids, flaws, the presence of a different material inside of the material to be evaluated, and any interface of the material with air or other materials may represent a remote discontinuity. The reflected radiofrequency signal is received by the same or a separate antenna, is provided to a control unit comprising a computer-based processor, and timed using as reference the transmitted signal or the signal reflected from the discontinuity between the antenna and the material to be evaluated. 
         [0013]    The computer-based processor determines the delay in time between the reference signal and other reflected signals, which may include undesired clutter. Where the magnitude of the clutter is below the magnitude of the signals reflected from remote discontinuities of the material, the computer-based processor identifies a peak level of magnitude associated with these discontinuities and determines the distance from such discontinuities to the surface of the material contiguous to the antenna. One or more evaluations over an area of the material provides the residual thickness of the material and the location of flaws inside the material at each evaluation to create an erosion profile of the remote surface of the material. 
         [0014]    In addition, the use of one or more antennas having an alternate configuration and the corresponding data processing allows the generation of cross-sectional images of the inside of the material under evaluation. This becomes particularly useful when evaluating a multilayered structure, such as the layers of refractory material surrounding the molten material in an industrial furnace. As a result, the system is capable of creating a tomographic view within the different layers of material to identify the location of remote discontinuities. More importantly, the system allows for the visualization of the presence of extraneous material within the material under evaluation, such that the penetration of molten material into the insulating material can be detected early. 
         [0015]    Therefore, by determining the rate of penetration of molten material into the surrounding material, it is possible to estimate the remaining operational life of the furnace, effectively extending the life of the furnace. This allows more effective and accurate scheduling to optimize the costly processes of furnace repairs, decommissioning, or replacement along with a significant reduction of the level of risk of an operational break or leakage of molten material. 
         [0016]    Furthermore, the system comprises a software management subsystem configured to enable a user to control one or more computer-based processors for handling the collected data. This data handling includes measuring, storing, monitoring, recording, processing, mapping, visualizing, transferring, analyzing, tracking, and reporting of these data for evaluating the status of the material under evaluation and generating an accurate estimation of the overall health of the furnace. In addition, the software management subsystem is capable of monitoring and controlling the system operations not only locally, but also remotely through a computer network or a cloud computing environment. 
         [0017]    By integrating a number of sensors, additional hardware, and a software management subsystem, and thereby significantly increasing the effective evaluation, monitoring, diagnosing, or tracking of one or more conditions related to the operational health of a furnace, as compared to standard techniques, the system is able to identify and determine the location of flaws and optimize the maintenance scheduling of costly and potentially risky assets. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The numerous advantages of the present invention may be better understood by those skilled in the art by reference to the accompanying drawings in which: 
           [0019]      FIG. 1  shows a schematic view of a monitoring system used to evaluate and monitor the status of a unit under test in accordance with certain aspects of a configuration. 
           [0020]      FIG. 2  shows a schematic view of a monitoring system used to evaluate and monitor the status of a unit under test in accordance with certain aspects of another configuration, wherein a computer-based processor is used for data processing. 
           [0021]      FIG. 3  shows a schematic view of a monitoring system used to evaluate and monitor the status of a furnace using a sensor head. 
           [0022]      FIG. 4  shows a schematic view of a monitoring system used to evaluate and monitor the status of a furnace using a probe. 
           [0023]      FIG. 5  shows a schematic view of a representation on a display of a portion of a wall forming part of an outer surface of a furnace. 
           [0024]      FIG. 6  shows a configuration of a management software architecture in accordance with certain aspects of a configuration. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]    The following description is of particular embodiments of the invention, set out to enable one to practice an implementation of the invention, and is not intended to limit the preferred embodiment, but to serve as a particular example thereof. Those skilled in the art should appreciate that they may readily use the conception and specific embodiments disclosed as a basis for modifying or designing other methods and systems for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent assemblies do not depart from the spirit and scope of the invention in its broadest form. 
         [0026]    In accordance with certain aspects of a configuration of the invention, a schematic top view of the components of a monitoring system  10 , used for a typical application of evaluating and monitoring or inspecting a unit under test (UUT)  18 , is shown in  FIG. 1 . 
         [0027]    Monitoring system  10  comprises a control unit  12 , a sensor head  14 , and a set of cables  16  to electrically connect or couple control unit  12  and sensor head  14 . Sensor head  14  is capable of transmitting one or more electromagnetic (EM) waves into a region around sensor head  14  as well as receiving the corresponding one or more EM waves from that region within a frequency range, preferably in a frequency band of 0.25 GHz to 30 GHz. 
         [0028]    Additionally, sensor head  14  may transmit a plurality of EM waves in the frequency domain, such that the time domain representation of this plurality of EM waves corresponds to a radiofrequency (RF) signal of short duration, for example a Gaussian, Rayleigh, Hermitian, or Laplacian pulse or of the like or a combination thereof. Alternatively, sensor head  14  may generate such type of pulse. In any case, the duration of the RF signal is preferably not larger than 5 nanoseconds. More specifically, sensor head  14  comprises an RF module, and more particularly an RF transceiver, preferably consisting of an RF transmitter and an RF receiver, and one or more antennas or probes. While an exemplary antenna configuration is described herein in accordance with a particularly preferred embodiment, a number of antenna configurations may be suitable for use with the sensor head  14  described herein, and more particularly those antenna configurations set forth in U.S. Patent No. 9,255,794 of Walton et al., and in U.S. Patent Application Publication No. US 2015/0276577 of Ruege et al., the specifications of which are incorporated herein by reference in their entireties. 
         [0029]    Additionally, sensor head  14 , apart from frequency domain or time domain RF-based approaches, may also use other technologies such as ultrasound, acoustic, eddy current, gamma rays and similar technologies. Furthermore, sensor head  14  comprises a computer-based processor with an executable computer code or software, capable of measuring and collecting data from the EM waves or RF signals received by sensor head  14 , and a data storage unit to store information pertinent to the data collected. 
         [0030]    During the inspection process, sensor head  14  is disposed in the vicinity of UUT  18 , such that, on the one hand, the signals transmitted by sensor head  14  are launched into the region of UUT  18  to be inspected, whereas on the other hand, the signals transmitted by sensor head  14  that are reflected by UUT  18  may be received by sensor head  14 . Furthermore, set of cables  16  comprises one or a combination of more than one of the following: control cables to activate or deactivate sensor head  14 , data communication cables for data transfer between control unit  12  and sensor head  14 , and power cables to transfer power between control unit  12  and sensor head  14 . This allows transmission of both raw data and processed data from sensor head  14  to control unit  12 . 
         [0031]    In addition, a switch or trigger may be installed along one or more lines of set of cables  16  to enable an in-line trigger that allows partial or total activation or deactivation of the functionality of sensor head  14 . Set of cables  16  may also include navigation buttons to assist the operator in tracking the location on UUT  18  to be inspected and communicating with control unit  12 . 
         [0032]    Control unit  12  comprises a computer-based processor, having executable computer code or software thereon, to control sensor head  14  and to manage the communications and data transfer between control unit  12  and sensor head  14  through set of cables  16 . Preferably, control unit  12  further comprises a storage unit to be able to store data and facilitate the processing of the data collected by sensor head  14 , and a display unit for displaying information. More preferably, control unit  12  is a portable device. Most preferably, control unit  12  comprises a handheld or wearable electronic device capable of storing and processing data as well as displaying information to a user, including the identification and location of the asset being evaluated, confirmation of the areas already inspected, and the sections pending for inspection. Those skilled in the art will recognize that the transfer of data between control unit  12  and sensor head  14  may be realized through a wireless communication channel via Bluetooth, Wi-Fi, or equivalent methods. 
         [0033]    Based on both the known transmitted signals and the signals measured by sensor head  14 , a status of UUT  18  may be determined by processing the collected data using the computer-based processor of control unit  12 . With continued reference to  FIG. 1 , it is noted that components of sensor head  14  and the computer-based processors of control unit  12  have not been shown as these components are not critical to the explanation of this configuration. 
         [0034]      FIG. 2  shows a schematic top view of monitoring system  10  in accordance with certain aspects of another configuration, wherein a computer-based processor  20 , having executable computer code or software thereon, is used to process the data collected by sensor head  14 . In addition, the data processed by computer-based processor  20  may be visually shown in a display  22 , which is connected to computer-based processor  20  through cable  24 . Computer-based processor  20 , display  22 , and cable  24  are commonly used devices that are well known in the prior art. 
         [0035]    Preferably, sensor head  14  transfers the data associated with UUT  18 , through set of cables  16 , to control unit  12 , which communicates with computer-based processor  20 . Those skilled in the art will realize that various methods exist to transfer the data collected by sensor head  14  to computer-based processor  20  for further processing and displaying, including a portable memory device that stores such data, a wired cable connecting control unit  12  or sensor head  14  to computer-based processor  20 , and a wireless communication channel between control unit  12  or sensor head  14  and computer-based processor  20 . 
         [0036]      FIG. 3  shows a particular configuration of monitoring system  10  in which UUT  18  consists of a furnace  30 , comprising a chamber  32  enclosing a molten material  34 , and a first layer  36 , a second layer  38 , a third layer  40 , and a fourth layer  42 , wherein each of these layers is made of refractory or insulating materials. Furnace  30  is representative of applications used in the glass, steel, and plastic industries. In these applications, chamber  32  is typically surrounded by multiple layers of material to prevent heat loss and leakage of molten material to the outside of furnace  30  and as a safety measure to workers and equipment operating in the surroundings of furnace  30 . 
         [0037]    Each of layers  36 ,  38 ,  40 , and  42  has an outer surface and an inner surface opposite the outer surface, such that the inner surface is closer to chamber  32 . Thus, the inner surface of first layer  36  of refractory material is contiguous to (i.e., in physical contact with) chamber  32 . Normally, during operation of furnace  30 , the inner walls of chamber  32  will degrade. The effects of this degradation include inner surface erosion, stress cracks, and refractory material diffusion into the molten material. Accordingly, molten material  34 , such as molten glass, at high temperatures erodes and degrades the inner walls of chamber  32  and surrounding layers  36 ,  38 ,  40 , and  42 , creating a high risk of molten material leakage to the outside of furnace  30 . Typical thickness values of refractory and insulation material of furnace walls range from  1  inch to  24  inches on the sidewalls. 
         [0038]    In general, monitoring a certain status of furnace  30  depends on the specific sensor head  14 , disposed in the vicinity of outer surface  43  of furnace  30 , used to collect data and connect to control unit  12  through set of cables  16 . In particular, the use of a refractory thickness sensor as sensor head  14 , enables monitoring system  10  to determine the thickness and thickness profile of one or more of layers  36 ,  38 ,  40 , and  42  of furnace  30 . Alternatively, the use of a furnace tomography sensor as sensor head  14 , enables monitoring system  10  to determine a thickness profile and assess the degree of penetration of molten material  34  into one or more of layers  36 ,  38 ,  40 , and  42  of furnace  30 . Those skilled in the art will realize that a plurality of sensors of the same type in either a monostatic or multistatic configuration, and other types of sensors may be used as sensor heads, including thermal imaging, temperature, and furnace bottom detection sensors. 
         [0039]    Typically, in industrial applications the access to certain regions of furnace  30  might be particularly difficult.  FIG. 4  shows an alternative configuration of monitoring system  10 , wherein sensor head  14  comprises three components: namely, an electronic device  14   a  comprising an RF transceiver, a computer-based processor with executable computer code or software thereon, and a data storage unit; an antenna or probe  14   b ; and a cable  14   c , such as a coaxial cable, to electrically connect device  14   a  to probe  14   b . This configuration allows setting up a unit of smaller size in the vicinity of outer surface  43  of furnace  30 , because probe  14   b  is separated from electronic device  14   a.    
         [0040]    Furthermore, one or more probes  14   b  may be permanently or temporarily installed in-situ over a plurality of locations of furnace  30 , especially in areas of difficult access. Preferably, in-situ probes  14   b  are installed in the vicinity of outer surface  43  of furnace  30 . Then, device  14   a  may connect to each probe  14   b  through connectorized cable  14   c  to collect the data corresponding to the area wherein each probe  14   b  is installed. Probe  14   b  need not be in physical contact with furnace  30  and can be mechanically actuated by a switch or trigger button located on control unit  12  or set of cables  16 . Similarly, probe  14   b  can be quickly activated by attaching a quick-connect cable  14   c . In addition, a plurality of sensors with communication capabilities may be installed in each of layers  36 ,  38 ,  40 , and  42  or chamber  32 , enclosing molten material  34 , to provide data to probe  14   b . Preferably, this plurality of sensors is installed during furnace construction or during a repair process. 
         [0041]    Moreover, a mechanical attachment, such as a pole, using a quick-connect system to easily connect to probe  14   b  may be used to prioritize usability of monitoring system  10 , to increase the accessibility of probe  14   b , and to extend the locations of furnace  30  that may be reachable by probe  14   b . Preferably, the mechanical attachment is extendable and flexible, such as a gooseneck type for accessing tight spots, and provides certain self-alignment with a wall of furnace  30 . More preferably, the mechanical attachment is also rugged, light weight, and collapsible to fit into a carry-on sized case. Those skilled in the art will realize that other types of mechanical attachments may be used to enhance the access of probe  14   b  to areas of furnace  30  that may be difficult to access. These mechanical attachments may include telescopic poles, foldable elements, angled-section arms, and retractable parts. 
         [0042]    In reference to  FIGS. 1 to 4 , in a preferred configuration, control unit  12  is capable of controlling and handling a plurality of sensor heads  14  and probes  14   b . The computer-based processor and the executable software of control unit  12  may enable the identification of the type of sensor head  14  connected to control unit  12  or the type of probe  14   b  attached to device  14   a , by initiating a handshaking protocol between control unit  12  and sensor head  14  or device  14   a . This handshaking protocol is similar to the one used by a computer to recognize a flash drive. Accordingly, once the type of sensor head  14  or probe  14   b  is identified, control unit  12  operates sensor head  14  or device  14   a  for monitoring the corresponding status of furnace  30 . 
         [0043]    Typically, control unit  12  is capable of connecting to a variety of sensor heads  14  and probes  14   b . Those skilled in the art will realize that a number of other types of sensors may be connected to control unit  12 , including temperature sensors to determine temperature profiles and furnace bottom sensors to determine the distance between the bottom of chamber  32  and outer surface  43  of furnace  30  in the area substantially parallel to the floor wherein furnace  30  is installed. 
         [0044]      FIG. 5  shows a schematic side view of a representation on a display of a portion of a wall  50 , which is part of outer surface  43  of a furnace. Wall  50  comprises a plurality of bricks  52  made of refractory material. A grid consisting of a first set of mapping labels  54 , vertically oriented, and a second set of mapping labels  56 , horizontally oriented, may be externally placed on outer surface  43 , to facilitate the tracking of the specific regions of the furnace being monitored in real time or over a certain period of time. Preferably, outer surface  43  is labeled with letters or numbers in rows and columns using labels  54 ,  56 . Labels  54 ,  56  should be capable of withstanding the relatively high temperatures, which may reach over 1000° F., on outer surface  43 . 
         [0045]    In reference to  FIGS. 1 to 5 , preferably, customized software is installed in control unit  12  to enable the mapping of outer surface  43  of furnace  30 , based on mapping labels  54 ,  56 . The dimensions and layout of furnace  30 , including each of layers  36 ,  38 ,  40 , and  42 , type of material, and layer thickness are setup in the customized software installed in control unit  12 . In addition, the rows and columns as mapped on outer surface  43  of furnace  30 , according to labels  54 ,  56 , are correspondingly mapped onto a software layout of furnace  30  and installed in control unit  12  to enable proper mapping and tracking of each inspection of a region of furnace  30 . 
         [0046]    In accordance with certain aspects of a configuration of the invention, an asset life optimization system comprises a monitoring system integrated with a management software subsystem. More specifically, in a preferred configuration, each of the above-described configurations, in reference to  FIGS. 1 to 4 , may be integrated with a management software subsystem to implement an asset life optimization system, wherein furnace  30  represents such asset. Thus, the management software subsystem may be used to perform and control the monitoring, recording, mapping, visualization, diagnosing, analysis, and tracking of the status of furnace  30 . In particular,  FIG. 6  shows a configuration of a management software subsystem architecture  60 , comprising a first software module  62  installed in control unit  12 , a cloud computer subsystem  64 , and a second software module  66  installed in a client computer  68 . Management software subsystem architecture  60  enables the data collection and storage by control unit  12 , the data transfer and processing, and the inspection reports generation. 
         [0047]    In reference to  FIGS. 1 to 6 , preferably, before inspecting an area of furnace  30 , a map of the design of furnace  30  is downloaded to control unit  12 . Then, a user may operate software module  62  to enter on control unit  12  the specific region of furnace  30  to be inspected. This may be done by selecting on control unit  12  the corresponding block or section, according to the identification of rows and columns on outer surface  43  of furnace  30 , in reference to mapping labels  54 ,  56 . 
         [0048]    More preferably, software module  62  enables one or more navigation buttons on control unit  12  to allow a user to select a region of furnace  30  to be inspected, or to control a function, such as triggering the collection of data, of sensor head  14  or device  14 a. During inspection, software module  62  stores on control unit  12  all the data collected for each inspected section of outer surface  43  of furnace  30 . 
         [0049]    Most preferably, the map of the design of furnace  30  is uploaded to cloud computer subsystem  64 , and second software module  66  allows downloading this map from cloud computer subsystem  64  to control unit  12 . Alternatively, software module  62  may be enabled to download this map directly from cloud computer subsystem  64 . 
         [0050]    Once the inspection is completed, software module  62  may be used to transfer the data, corresponding to the inspected block or section of furnace  30 , from control unit  12  to cloud computer subsystem  64 . Then, second software module  66  may be used to download the data from cloud computer subsystem  64  into client computer  68 . Alternatively, a user may operate second software module  66  to enable the transfer of data from control unit  12  to cloud computer subsystem  64 . In any case, second software module  66  may be used for evaluation and analysis of the data stored in either cloud computer subsystem  64  or client computer  68 . This data analysis may include the use of data processing and image processing algorithms and signal processing visualization techniques. 
         [0051]    After the collected data have been processed, software module  66  may generate inspection reports to organize inspection data, visualize potential molten material penetration, and provide analytics on furnace degradation to optimize the maintenance plan of furnace  30 . Typically, an inspection report may include a two-dimensional or a three-dimensional visualization providing information of the outer walls of furnace  30 . For example, a report may indicate the thickness of the refractory material, with mapping labels  54 ,  56  or color-coded representation, corresponding to regions where the thickness may have reached certain levels, according to a predefined criteria. 
         [0052]    More specifically, an inspection report may include a two-dimensional visualization of outer surface  43  of furnace  30 , similar to the representation shown in 
         [0053]      FIG. 5 , displaying color-coded or warning information, corresponding to a flaw or the thickness of the refractory material and according to predetermined thickness levels (e.g., normal, moderate, or critical) for each area of outer surface  43  that have been inspected. Likewise, an inspection report may include a three-dimensional visualization of a cross-sectional view of wall  50  showing the status of each of layers  36 ,  38 ,  40 , and  42  of furnace  30 . 
         [0054]    In addition, inspection reports may provide information in terms of a thickness profile over time for a specific block or section of furnace  30  to observe the trend of the material degradation and estimate appropriate times for repairs or furnace utilization. Other inspection reports may include the level of penetration of molten material  34  into each of layers  36 ,  38 ,  40 , and  42  of furnace  30  and temperature corresponding to a specific block or section of furnace  30  to identify areas of potential breakage and prevent damage to furnace  30  and the surrounding equipment and personnel. Software module  66  is able to keep record of each inspection, compute refractory material erosion rate, provide a history of the degradation of each of layers  36 ,  38 ,  40 , and  42  of furnace  30 , determine the impact of the melting process, and evaluate the performance of each of layers  36 ,  38 ,  40 , and  42  of furnace  30  for specific types of molten material used. 
         [0055]    In another configuration, and in reference to  FIGS. 2 and 6 , client computer  68  may be directly connected to control unit  12 . In other words, client computer  68  in  FIG. 6  may be used as computer-based processor  20  in  FIG. 2 . In this case, all data collection, storing, transferring, processing, and reporting may be performed locally. 
         [0056]    Those skilled in the art will realize that client computer  68  may be connected to or integrated with an external computer or server having a secure database and a backup storage system. This external computer or server may replace cloud computer subsystem  64 . Preferably this external computer or server comprises a web application such that a user can remotely access and visualize the results of a furnace inspection through a web or smartphone platform. Likewise, those skilled in the art will recognize that data processing and image processing algorithms may be implemented by using one or a combination of more than one technique. These techniques may include Fourier transform, spectral analysis, frequency- and time-domain response analyses, digital filtering, convolution and correlation, decimation and interpolation, adaptive signal processing, waveform analysis, and data windows and phase unwrapping for data processing; and time domain, back projection, delay and sum, synthetic aperture radar imaging, back propagation, inverse scattering, and super-resolution, either with or without the application of differential imaging, for image processing. 
         [0057]    The various embodiments have been described herein in an illustrative manner, and it is to be understood that the terminology used is intended to be in the nature of to words of description rather than of limitation. Any embodiment herein disclosed may include one or more aspects of the other embodiments. The exemplary embodiments were described to explain some of the principles of the present invention so that others skilled in the art may practice the invention. Obviously, many modifications and variations of the invention are possible in light of the above teachings. The present invention may be practiced otherwise than as specifically described within the scope of the appended claims and their legal equivalents. 
         [0058]    The various embodiments have been described herein in an illustrative manner, and it is to be understood that the terminology used is intended to be in the nature of words of description rather than of limitation. Any embodiment herein disclosed may include one or more aspects of the other embodiments. The exemplary embodiments were described to explain some of the principles of the present invention so that others skilled in the art may practice the invention. Obviously, many modifications and variations of the invention are possible in light of the above teachings. The present invention may be practiced otherwise than as specifically described within the scope of the appended claims and their legal equivalents.