Defect detection in freight railcar tapered-roller bearings using vibration techniques

Currently, there are two types of defect detection systems used to monitor the health of freight railcar bearings in service: wayside hot-box detection systems and trackside acoustic detection systems. These systems have proven to be inefficient in accurately determining bearing health, especially in the early stages of defect development. To that end, a prototype onboard bearing condition monitoring system has been developed and validated through extensive laboratory testing and a designated field test in 2015 at the Transportation Technology Center, Inc. in Pueblo, CO. The devised system can accurately and reliably characterize the health of bearings based on developed vibration thresholds and can identify defective tapered-roller bearing components with defect areas smaller than 12.9 cm2 while in service

Vibration-Based Defect Detection for Freight Railcar Tapered-Roller Bearings

The railroad industry currently utilizes two wayside detection systems to monitor the health of freight railcar bearings in service: The Trackside Acoustic Detection System (TADS™) and the wayside Hot-Box Detector (HBD). TADS™ uses wayside microphones to detect and alert the conductor of high risk defects. Many defective bearings may never be detected by TADS™ due to the fact that a high risk defect is considered a spall which spans more than 90% of a bearing’s raceway, and there are less than 20 systems in operation throughout the United States and Canada. Much like the TADS™, the HBD is a device that sits on the side of the rail tracks and uses a non-contact infrared sensor to determine the temperature of the train bearings as they roll over the detector. The accuracy and reliability of the temperature readings from this wayside detection system have been concluded to be inconsistent when comparing several laboratory and field studies. The measured temperatures can be significantly different from the actual operating temperature of the bearings due to several factors such as the class of railroad bearing and its position on the axle relative to the position of the wayside detector. Over the last two decades, a number of severely defective bearings were not identified by several wayside detectors, some of which led to costly catastrophic derailments. In response, certain railroads have attempted to optimize the use of the temperature data acquired by the HBDs. However, this latter action has led to a significant increase in the number of non-verified bearings removed from service. In fact, about 40% of the bearings removed from service in the period from 2001 to 2007 were found to have no discernible defects. The removal of non-verified (defect-free) bearings has resulted in costly delays and inefficiencies. Driven by the need for more dependable and efficient condition monitoring systems, the University Transportation Center for Railway Safety (UTCRS) research team at the University of Texas Rio Grande Valley (UTRGV) has been developing an advanced onboard condition monitoring system that can accurately and reliably detect the onset of bearing failure. The developed system currently utilizes temperature and vibration signatures to monitor the true condition of a bearing. This system has been validated through rigorous laboratory testing at UTRGV and field testing at the Transportation Technology Center, Inc. (TTCI) in Pueblo, CO. The work presented here provides concrete evidence that the use of vibration signatures of a bearing is a more effective method to assess the bearing condition than monitoring temperature alone. The prototype bearing condition monitoring system is capable of identifying a defective bearing with a defect size of less than 6.45 cm2 (1 in2) using the vibration signature, whereas, the temperature profile of that same bearing will indicate a healthy bearing that is operating normally

Structural integrity of conventional and modified railroad bearing adapters for onboard monitoring

This paper presents a detailed study of the structural integrity of conventional and modified railroad bearing adapters for onboard monitoring applications. Freight railcars rely heavily on weigh bridges and stations to determine cargo load. As a consequence, most load measurements are limited to certain physical railroad locations. This limitation provided an opportunity for an optimized sensor that could potentially deliver significant insight on bearing condition monitoring as well as load information. Bearing adapter modifications (e.g. cut outs) were necessary to house the sensor and, thus, it is imperative to determine the reliability of the modified railroad bearing adapter, which will be used for onboard health monitoring applications. To this end, this study quantifies the impact of the proposed modifications on the adapter structural integrity through a series of experiments and finite element analyses. The commercial software Algor 20.3TM is used to conduct the stress finite element analyses. Different loading scenarios are simulated with the purpose of obtaining the conventional and modified bearing adapter stresses during normal and abnormal operating conditions. This information is then used to estimate the lifetime of these bearing adapters. Furthermore, this paper presents an experimentally validated finite element model which can be used to attain stress distribution maps of these bearing adapters in different service conditions. The maps are also useful for identifying areas of interest for an eventual inspection of conventional or modified railroad bearing adapters in the field

Fatigue Life Estimation of Modified Railroad Bearing Adapters for Onboard Monitoring Applications

This paper presents a study of the fatigue life (i.e. number of stress cycles before failure) of Class K cast iron conventional and modified railroad bearing adapters for onboard monitoring applications under different operational conditions based on experimentally validated Finite Element Analysis (FEA) stress results. Currently, freight railcars rely heavily on wayside hot-box detectors (HBDs) at strategic intervals to record bearing cup temperatures as the train passes at specified velocities. Hence, most temperature measurements are limited to certain physical railroad locations. This limitation gave way for an optimized sensor that could potentially deliver significant insight on continuous bearing temperature conditions. Bearing adapter modifications (i.e. cut-outs) were required to house the developed temperature sensor which will be used for onboard monitoring applications. Therefore, it is necessary to determine the reliability of the modified railroad bearing adapter. Previous work done at the University Transportation Center for Railway Safety (UTCRS) led to the development of finite element model with experimentally validated boundary conditions which was utilized to obtain stress distribution maps of conventional and modified railroad bearing adapters under different service conditions. These maps were useful for identifying areas of interest for an eventual inspection of railroad bearing adapters in the field. Upon further examination of the previously acquired results, it was determined that one possible mode of adapter failure would be by fatigue due to the cyclic loading and the range of stresses in the railroad bearing adapters. In this study, the authors experimentally validate the FEA stress results and investigate the fatigue life of the adapters under different extreme case scenarios for the bearing adapters including the effect of a railroad flat wheel. In this case, the flat wheel translates into a periodic impact load on the bearing adapter. The Stress-Life approach is used to calculate the life of the railroad bearing adapters made out of cast iron and subjected to cyclic loading. From the known material properties of the adapter (cast iron), the operational life is estimated with a mathematical relationship. The Goodman correction factor is used in these life prediction calculations in order to take into account the mean stresses experienced by these adapters. The work shows that the adapters have infinite life in all studied cases

THE USE OF NEAR INFRARED REFLECTANCE FOR EVALUATING COTTON FINENESS AND MATURITY

The U.S. Department of Agriculture has proposed to develop Ii new high speed, high volume technique to assess cotton quality. This goal has led us to investigate the feasibility of near infrared reflectance spectroscopy as a technique for evaluating cotton fiber perimeter size and wall thickness, two of the physical characteristics used in the evaluation of cotton fineness and maturity. In order to isolate the effects of perimeter size and wall thickness, nineteen cotton samples were selected on the basis of their having a nonsignificant correlation between these 2 measurements. The reflectance spectra from 1100 to 2500 nanometers was recorded at every other wavelength. The 700 independent variables were transformed by log (1/ reflectance). Due to the multicollinearity of the independent variables, the principle components were used in a multiple regression with data obtained from the reference method (arealometer) for the two dependent variables, perimeter size and wall thickness. The regression analysis of perimeter size and wall thickness on the principle components gave R2\u27S of 0.229 and 0.943 respectively

An investigation into wayside hot-box detector efficacy and optimization

Wayside hot-box detectors (HBDs) are devices used to assess the health of railcar components including bearings, axles, and brakes by monitoring their temperatures. HBDs use infrared (IR) sensors to record the temperatures of railroad bearings. Bearings that trigger an alarm or exhibit warm trending are removed and sent for inspection. In many cases, no discernable defects were found in the flagged bearings. Motivated by this finding, an investigation was conducted which included performing a controlled field test as well as exhaustive laboratory testing utilizing an HBD simulator. Data acquired from field and laboratory testing was used to evaluate the accuracy and efficacy of wayside HBDs. The results suggest that the scanning location on the bearing cup significantly affects the temperature measurement. Different calibrations for the field- and laboratory-acquired data were also explored. An optimized calibration technique along with proper IR sensor alignment can markedly improve the accuracy of HBD measurements

Estimating the Outer Ring Defect Size and Remaining Service Life of Freight Railcar Bearings Using Vibration Signatures

The railroad industry currently utilizes two wayside detection systems to monitor the health of freight railcar bearings in service: The Trackside Acoustic Detection System (TADS™) and the wayside Hot-Box Detector (HBD). TADS™ uses wayside microphones to detect and alert the conductor of high-risk defects. Many defective bearings may never be detected by TADS™ since a high-risk defect is a spall which spans more than 90% of a bearing’s raceway, and there are less than 20 systems in operation throughout the United States and Canada. Much like the TADS™, the HBD is a device that sits on the side of the rail-tracks and uses a non-contact infrared sensor to determine the temperature of the train bearings as they roll over the detector. These wayside detectors are reactive in the detection of a defective bearing and require emergency stops in order to replace the wheelset containing the defective bearing. These costly and inefficient train stoppages can be prevented if a proper maintenance schedule can be developed at the onset of a defect initiating within the bearing. This proactive approach would allow for railcars with defective bearings to remain in service operation safely until reaching scheduled maintenance. Driven by the need for a proactive bearing condition monitoring system in the rail industry, the University Transportation Center for Railway Safety (UTCRS) research group at the University of Texas Rio Grande Valley (UTRGV) has been developing an advanced onboard condition monitoring system that can accurately and reliably detect the onset of bearing failure using temperature and vibration signatures of a bearing. This system has been validated through rigorous laboratory testing at UTRGV and field testing at the Transportation Technology Center, Inc. (TTCI) in Pueblo, CO. The work presented here builds on previously published work that demonstrates the use of the advanced onboard condition monitoring system to identify defective bearings as well as the correlations developed for spall growth rates of defective bearing outer rings (cups). Hence, the system uses the root-mean-square (RMS) value of the bearing’s acceleration to assess its health. Once the bearing is determined to have a defective outer ring, the RMS value is then used to estimate the defect size. This estimated size is then used to predict the remaining service life of the bearing. The methodology proposed in this paper can prove to be a useful tool in the development of a proactive and cost-efficient maintenance cycle for railcar owners

Desarrollo de una aplicación web y móvil empleando prácticas ágiles para la pesca y hostería San Nicolás.

ThisprojectdealswiththedevelopmentofawebandmobileapplicationforthemanagementofreservationsandordersinTheFishingandInn"SanNicolás",asadeterminingfactorinthemanagementofthereservationcustomerandordermanagementbythestaff,throughtheuseofagilepracticesoftheinnlocatedinIlluchiparishbelongingtoLatacunga,provinceCotopaxi,theimportanceoftheimplementationofthesoftwarewillallowthegenerationofonlinereservationsandordermanagementtoimproveaccesstoinformationanddatawithintegrity,securityincustomerreservationsandordersmanagedbythestaffoftheestablishment,streamliningthem;SCRUMmethodwasusedtodeveloptheapplication,intheanalysisitwaspossibletodeterminethedesignandcoding.Themostimportantrequirementsarethemanagementofreservationsforthecustomerandordermanagementfortheestablishmentstaff,thetoolstobeusedinthisprojectarethePHPlanguagewithLaravelframework,whichoffersfunctionalitynecessaryforthedevelopmentofeasy,modern,orderlyandsecurewebapplications,theMySQLdatabasemanagerthemobileapplicationAndroidStudiowasusedandtheusageofagilepractices.Itwasdeterminedthattheprocesseswerecarriedoutmanuallyinanotebookwereverytimeconsumingandconfusing,withtheimplementationofareservationmanagementsystemandordermanagement,itwaspossibletohaveorderlyreservationsandreductionofthetimeittookthestafftomakearestaurantorder,bettercontrolofinformationandintegrityofthesame,obtainingreliableandeffectiveinformation.El presente proyecto trata sobre el desarrollo de una aplicación web y móvil para la gestión de reservas y pedidos en La Pesca y Hostería “San Nicolás”, como factor determinante, en el manejo del reserva – cliente y el manejo de pedidos por el personal, mediante el uso de prácticas agiles de la hostería ubicada en la parroquia Illuchi perteneciente al catón Latacunga provincia de Cotopaxi, la importancia de la implementación del Software permitirá la generación de reservas de forma online y gestión de pedidos, para mejorar el acceso a la información y datos con integridad, seguridad en las reservas cliente y pedidos gestionada por el personal del establecimiento, agilizando los mismos; para desarrollar la aplicación se utilizó el método SCRUM, en el análisis se pudo determinar el diseño y codificación. Los requerimientos más importantes están la gestión de reservas para el cliente y la gestión de pedidos para el personal de establecimiento, las herramientas a utilizar en este proyecto son el lenguaje PHP con framework Laravel, ofrece funcionalidades necesarias para el desarrollo de aplicaciones web fáciles, modernas, ordenadas y seguras, el gestor de base de datos MySQL, para la aplicación móvil se utilizó Android Studio y la utilización de prácticas agiles. Se determinó los procesos que se llevaba manualmente en un cuaderno era muy demoroso y confuso, con la implementación de sistema gestión de reservas y gestión de pedidos, se pude tener reservas ordenadas y reducción del tiempo que llevaba al personal hacer un pedido de restaurante, un mejor control de información e integridad de la misma, obteniendo información confiable y eficaz

Influencia de la variación del corte sobre el rendimiento y los ingresos económicos de la industria del aserrío

Ciclo Optativo de Especialización y Profesionalización en Gestión de Calidad Total y ProductividadActualmente la industria de aserrío aporta en gran medida al dinamismo económico de las ciudades donde se desarrolla, sin embargo el uso ineficiente de la materia prima genera problemas sociales, ambientales y económicos, por ello la necesidad de realizar investigaciones que aporten al correcto uso del recurso. El presente estudio se realizó con la finalidad de determinar y analizar la influencia que tiene la variación del corte, que se genera en la sierra principal, en el rendimiento y los ingresos económicos de los aserraderos ubicados en la Ciudad de Pucallpa Departamento de Ucayali, y proponer un sistema de control de la variación del corte. En base a la metodología de “Los Puntos Múltiples”, se registró las medidas de las piezas de madera de 2” (pulgadas) de espesor, en 3 aserraderos representativos de la tecnología de la ciudad; con lo cual se pudo observar que ninguno de los aserraderos; presenta una “Variación de Corte Aceptable o Estadísticamente Controlada”, no cortan en base a la “Dimensión Optima” y que presentan cortes con exceso en el espesor. Los aserraderos en estudio (A1, A2 y A3) perdieron 917.5 m3, 616.1m3 y 645.1 m3, respectivamente, en volumen de madera por cortar con exceso en el espesor; así también podrían haber recibido ingresos económicos para año 2011 de S/. 86930; S/. 55767 y S/. 51966, respectivamente, si cortaban en su dimensión óptima.Tesi

An Assessment of Surface Properties and Moisture Uptake of Nonwoven Fabrics from Ginning By-products

Greige (raw) cotton by-products resulting from cotton ginning and mill processes have long been bleached for use in absorbent nonwoven products. The potential to use greige cotton by-products as an economical source for absorbent nonwoven blends is explored. The nonwoven hydroentanglement of greige cotton lint with cotton gin motes and comber noils blends was analyzed for fiber surface polarity, swelling, and absorbance to assess properties with potential usefulness in absorbent nonwovens. The electrokinetic analysis of the fabric surface gives a composite picture of the relative hydrophilic/hydrophobic polarity absorbency and swelling properties. Nonwoven fabrics made with cleaned greige cotton lint separately blended with comber noils and ginning motes at 40:60 and 60:40 blend ratios demonstrated charge, swell, and percent moisture uptake profiles that are characteristic of the fabrics’ crystalline/amorphous cellulosic content with some variance in swelling properties. However, cellulose crystallite size varied. X-ray diffraction patterns of the three different cotton constituents displayed similar crystalline cellulose compositions. An electrochemical double-layer analysis of charge based on a pH titration (ζplateau) was employed to measure the relative fiber and fabric surface polarity which varied slightly between -21 and -29 mV. A relationship of fiber swelling (∆ζ) and percent moisture content is apparent when greige cotton lint and other fibers are blended. The blended nonwoven materials possess absorbent properties characterized by similar moisture uptake (7.1-9.5 %) and fiber polarity, but some variation in swelling is based on the by-product additive and its percent content. The crystallinity, electrokinetic, and water binding properties of the nonwoven by-product materials are discussed in the context of the molecular features water, cellulose, and greige cotton components that enhance potential uses as absorbent nonwoven end-use products