A material constant B bearing width C basic dynamic load rating D bearing outside diameter Dr roller diameter E Young’s modulus Fr radial load of the bearing INT integer function L fatigue life Lr roller length Qr resultant normal force in the roller‐main race contact St Stribeck’s constant Uz local displacement inside the bearing elements Z depth of occurrence of maximal von Mises stresses along the x axis Zr number of rollers in the bearing b half width of the contact c exponent in the equation determining the survival prob‐ ability d bearing bore diameter dbi diameter of the inner ring raceway dbo diameter of the outer ring raceway e Weibull slope g radial clearance in the bearing h exponent in the equation determining the survival prob‐ ability i inner raceway j number of roller l length of the roller‐main race contact area o outer raceway n number of pairs of loaded items rb radius of the main race rc roller chamfer u number of load cycles per one revolution δmax maximum elastic deformation δc total displacement of the bearing axis ν Poisson’s constant σ maximal von Mises stress occurring along the x axis Chudzik A, WArdA B. Effect of radial internal clearance on the fatigue life of the radial cylindrical roller bearing. Eksploatacja i Niezawodnosc – Maintenance and reliability 2019; 21 (2): 211–219, http://dx.doi.org/10.17531/ein.2019.2.4.
材料常数B轴承宽度C基本动态负载评级博士D轴承外径辊直径E杨氏模量Fr径向载荷的轴承INT整数函数L疲劳寿命Lr滚子长度Qr合成法向力在滚筒上应承担的主要种族联系圣Stribeck常数是乌斯当地位移内方位元素Z发生最大深度•冯•米塞斯应力沿着x轴Zr的滚轴轴承B C指数的一半宽度的联系方程确定的生存概率检测能力d轴承内径dbi直径的内圈滚道dbo直径的外环水沟e威布尔坡g在轴承径向间隙h指数方程确定的生存概率检测能力我内心水沟j的辊的长度l辊量主要种族接触面积o外水沟n对加载项的数量rb半径的主要种族rc辊槽每一个革命δu载荷的循环次数最大最大弹性变形δc轴承轴总位移ν泊松常数σ沿x轴发生的最大von Mises应力Chudzik A, WArdA b径向内间隙对径向圆柱滚子轴承疲劳寿命的影响Eksploatacja i Niezawodnosc -维护和可靠性2019;21 (2): 211-219, http://dx.doi.org/10.17531/ein.2019.2.4。
{"title":"Effect of radial internal clearance on the fatigue life of the radial cylindrical roller bearing","authors":"A. Chudzik, B. Warda","doi":"10.17531/ein.2019.2.4","DOIUrl":"https://doi.org/10.17531/ein.2019.2.4","url":null,"abstract":"A material constant B bearing width C basic dynamic load rating D bearing outside diameter Dr roller diameter E Young’s modulus Fr radial load of the bearing INT integer function L fatigue life Lr roller length Qr resultant normal force in the roller‐main race contact St Stribeck’s constant Uz local displacement inside the bearing elements Z depth of occurrence of maximal von Mises stresses along the x axis Zr number of rollers in the bearing b half width of the contact c exponent in the equation determining the survival prob‐ ability d bearing bore diameter dbi diameter of the inner ring raceway dbo diameter of the outer ring raceway e Weibull slope g radial clearance in the bearing h exponent in the equation determining the survival prob‐ ability i inner raceway j number of roller l length of the roller‐main race contact area o outer raceway n number of pairs of loaded items rb radius of the main race rc roller chamfer u number of load cycles per one revolution δmax maximum elastic deformation δc total displacement of the bearing axis ν Poisson’s constant σ maximal von Mises stress occurring along the x axis Chudzik A, WArdA B. Effect of radial internal clearance on the fatigue life of the radial cylindrical roller bearing. Eksploatacja i Niezawodnosc – Maintenance and reliability 2019; 21 (2): 211–219, http://dx.doi.org/10.17531/ein.2019.2.4.","PeriodicalId":309533,"journal":{"name":"Ekspolatacja i Niezawodnosc - Maintenance and Reliability","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123300774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Marczuk, W. Misztal, P. Savinykh, Nikolay Turbanov, A. Isupov, D. Zyryanov
The homogeneity of mixing various feed mixture ingredients and the reliability of mixers directly depend on the constructional features of mixing devices and operational parameters of their work. This article presents a theoretical underpinning for the structural (design) specifications of a horizontal ribbon auger mixer (blender) with regard to the fulfilment of the condition when the material is transported by auger tapes in different directions, ensuring the efficient mixing of the feed mixture ingredients and timely material unloading from the mixer tank (hopper). The performed optimization of the structural and operational specifications as a result of experimental studies has allowed to increase the reliability of the mixer and to determine the homogeneity coefficient of the finished product, which reaches its the highest value of 94.13% with the forward direction of rotation of the mixer movable operating elements, when mixing time is 13 minutes and when the tank load is 52.4% of its volume.
{"title":"Improving efficiency of horizontal ribbon mixer by optimizing its constructional and operational parameters","authors":"A. Marczuk, W. Misztal, P. Savinykh, Nikolay Turbanov, A. Isupov, D. Zyryanov","doi":"10.17531/ein.2019.2.5","DOIUrl":"https://doi.org/10.17531/ein.2019.2.5","url":null,"abstract":"The homogeneity of mixing various feed mixture ingredients and the reliability of mixers directly depend on the constructional features of mixing devices and operational parameters of their work. This article presents a theoretical underpinning for the structural (design) specifications of a horizontal ribbon auger mixer (blender) with regard to the fulfilment of the condition when the material is transported by auger tapes in different directions, ensuring the efficient mixing of the feed mixture ingredients and timely material unloading from the mixer tank (hopper). The performed optimization of the structural and operational specifications as a result of experimental studies has allowed to increase the reliability of the mixer and to determine the homogeneity coefficient of the finished product, which reaches its the highest value of 94.13% with the forward direction of rotation of the mixer movable operating elements, when mixing time is 13 minutes and when the tank load is 52.4% of its volume.","PeriodicalId":309533,"journal":{"name":"Ekspolatacja i Niezawodnosc - Maintenance and Reliability","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115062341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The flow of significant current through electric contacts may lead to contact welding. In a.c. circuits this phenomena is not only dependent on properties of contact material (i.e. resistance to welding) but on the phase in which current is switched on. Welding tendency for contact materials made from AgNi, AgCdO and AgSnO2 was evaluated based on selected phase at which make operation took place. The test circuit was protected by overcurrent apparatus to simulate real working environment. It is observed that welding tendency for the selected contact materials is contingent to current phase at which make operation is done.
{"title":"Welding tendency for selected contact materials under different switching conditions","authors":"A. Książkiewicz, J. Janiszewski","doi":"10.17531/EIN.2019.2.7","DOIUrl":"https://doi.org/10.17531/EIN.2019.2.7","url":null,"abstract":"The flow of significant current through electric contacts may lead to contact welding. In a.c. circuits this phenomena is not only dependent on properties of contact material (i.e. resistance to welding) but on the phase in which current is switched on. Welding tendency for contact materials made from AgNi, AgCdO and AgSnO2 was evaluated based on selected phase at which make operation took place. The test circuit was protected by overcurrent apparatus to simulate real working environment. It is observed that welding tendency for the selected contact materials is contingent to current phase at which make operation is done.","PeriodicalId":309533,"journal":{"name":"Ekspolatacja i Niezawodnosc - Maintenance and Reliability","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124907258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Industrial equipment or systems are usually constructed with kout-of-n:G subsystems in series to fulfill a specified function[14]. The k-out-of-n:G structure is a common type of redundancy used to improve the reliability and availability of engineering systems. A kout-of-n:G system refers to a system that is functional if and only if at least k out of n components within the system are functional[31]. Two types of components exist in the k-out-of-n:G system, which are acYu WAng Linhan guo Meilin Wen Yi YAng
工业设备或系统通常由一系列的k -n:G子系统组成，以实现特定的功能[14]。k / n:G结构是一种常用的冗余结构，用于提高工程系统的可靠性和可用性。k -n:G系统是指当且仅当系统内n个成分中至少有k个是功能性的系统[31]。k- of-n:G体系中存在两种组分，分别是:acYu, WAng, Linhan, guo, Meilin, Wen, Yi YAng
{"title":"Availability analysis for a multi-component system with different k-out-of-n:G warm standby subsystems subject to suspended animation","authors":"Yu Wang, Linhan Guo, M. Wen, Yi Yang","doi":"10.17531/ein.2019.2.14","DOIUrl":"https://doi.org/10.17531/ein.2019.2.14","url":null,"abstract":"Industrial equipment or systems are usually constructed with kout-of-n:G subsystems in series to fulfill a specified function[14]. The k-out-of-n:G structure is a common type of redundancy used to improve the reliability and availability of engineering systems. A kout-of-n:G system refers to a system that is functional if and only if at least k out of n components within the system are functional[31]. Two types of components exist in the k-out-of-n:G system, which are acYu WAng Linhan guo Meilin Wen Yi YAng","PeriodicalId":309533,"journal":{"name":"Ekspolatacja i Niezawodnosc - Maintenance and Reliability","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129045013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The paper describes a system for monitoring and diagnosing a gantry. The main goal of the system is to acquire, visualize and monitor vibration levels of the gantry crucial elements. The system is also equipped with a computing and analytical part which enables predictive maintenance related to the vibration level assessment. The system architecture can be used in other applications too, i.e. those which require a wireless network of vibration sensors to carry out diagnostic tasks.
{"title":"Monitoring and maintenance of a gantry based on a wireless system for measurement and analysis of the vibration level","authors":"M. Sikora, K. Szczyrba, Ł. Wróbel, M. Michalak","doi":"10.17531/ein.2019.2.19","DOIUrl":"https://doi.org/10.17531/ein.2019.2.19","url":null,"abstract":"The paper describes a system for monitoring and diagnosing a gantry. The main goal of the system is to acquire, visualize and monitor vibration levels of the gantry crucial elements. The system is also equipped with a computing and analytical part which enables predictive maintenance related to the vibration level assessment. The system architecture can be used in other applications too, i.e. those which require a wireless network of vibration sensors to carry out diagnostic tasks.","PeriodicalId":309533,"journal":{"name":"Ekspolatacja i Niezawodnosc - Maintenance and Reliability","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123924715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the era of developing technology, ICE forms the used sources applied to drive vehicles, machines and a variety of equipment. We can assume that despite its numerous drawbacks, ICE will remain to play the role of the dominant source of power for many years [9,12]. The lubrication system forms one of the most important systems in an engine, and a lubricating oil forms its integral part. In order to adequately verify the properties of oils during operation, there is a need to easily and accurately diagnose its quality. This fact leads to the need to adequately select a representative parameter by means of which it is possible to monitor changes occurring during its exploitation. Modern engine oils consist of various components and additives, by which a number of stringent operational requirements can be achieved and realized. Therefore, it is important to adopt and select such research methods and quantities that meet the requirements of a diagnostic parameter, can be applied to analyze the quality of the oil. The assessment of oil wear in an engine currently forms one of the most dynamically developing trends in research and is of interest to many scientific institutions [7]. This subject also forms the focus of interest of private companies operating vehicles due to the practical and economic outcomes that can be valuable to them [5,6]. All mechanisms or components of equipment are subjected to the processes of aging and wear so along with aging, engine oil changes its lubricating properties, which adversely affects the characteristics of the lubrication system. Heterogeneous conditions of vehicle and machine operaleszek gomółka andrzej auguSTynowicz
在科技发展的时代，ICE形成了用于驱动车辆、机器和各种设备的使用源。我们可以假设，尽管有许多缺点，内燃机仍将在许多年内扮演主要电力来源的角色[9,12]。润滑系统是发动机中最重要的系统之一，润滑油是其不可缺少的组成部分。为了在运行过程中充分验证油品的性能，需要对油品质量进行简单、准确的诊断。这一事实导致需要充分选择一个有代表性的参数，通过该参数可以监视在其开发过程中发生的变化。现代发动机油由各种成分和添加剂组成，通过这些成分和添加剂可以达到和实现许多严格的操作要求。因此，重要的是采用和选择这样的研究方法和数量，满足诊断参数的要求，可以应用于分析油的质量。发动机机油磨损的评估是目前研究中最具活力的发展趋势之一，也是许多科学机构感兴趣的问题[7]。这一主题也形成了私营公司运营车辆的兴趣焦点，因为其实际和经济成果可能对他们有价值[5,6]。设备的所有机构或部件都会经历老化和磨损的过程，因此随着老化，发动机油的润滑性能会发生变化，从而对润滑系统的特性产生不利影响。车辆和机器操作的异质条件[zek gomółka andrzej august stynowicz]
{"title":"Evaluation of applicability of dielectric constant in monitoring aging processes in engine oils","authors":"L. Gomółka, A. Augustynowicz","doi":"10.17531/ein.2019.2.1","DOIUrl":"https://doi.org/10.17531/ein.2019.2.1","url":null,"abstract":"In the era of developing technology, ICE forms the used sources applied to drive vehicles, machines and a variety of equipment. We can assume that despite its numerous drawbacks, ICE will remain to play the role of the dominant source of power for many years [9,12]. The lubrication system forms one of the most important systems in an engine, and a lubricating oil forms its integral part. In order to adequately verify the properties of oils during operation, there is a need to easily and accurately diagnose its quality. This fact leads to the need to adequately select a representative parameter by means of which it is possible to monitor changes occurring during its exploitation. Modern engine oils consist of various components and additives, by which a number of stringent operational requirements can be achieved and realized. Therefore, it is important to adopt and select such research methods and quantities that meet the requirements of a diagnostic parameter, can be applied to analyze the quality of the oil. The assessment of oil wear in an engine currently forms one of the most dynamically developing trends in research and is of interest to many scientific institutions [7]. This subject also forms the focus of interest of private companies operating vehicles due to the practical and economic outcomes that can be valuable to them [5,6]. All mechanisms or components of equipment are subjected to the processes of aging and wear so along with aging, engine oil changes its lubricating properties, which adversely affects the characteristics of the lubrication system. Heterogeneous conditions of vehicle and machine operaleszek gomółka andrzej auguSTynowicz","PeriodicalId":309533,"journal":{"name":"Ekspolatacja i Niezawodnosc - Maintenance and Reliability","volume":" 43","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120834176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Many chemical engineering products are created as a result of processes carried out using technological lines in which chemical reactors play a key role. A chemical reactor is a vessel adapted to carry out reactions taking place inside it. The purpose of industrial tank reactors is to ensure optimal economic parameters of chemical processes [18]. It can be achieved by the appropriate reactor design and by the skillful overlap of the three types of sub-processes occurring inside the reactor, namely the transfer of mass, momentum and heat. In this way, process control can be based on a dynamic selection of parameters such as: mixing intensity, temperature, pressure, substrate ratios and others. The presented research included reactors in which reactions take place between solid and liquid as well as gas and liquid. The tank reactor diagram is shown in Fig. 1. The first type of reaction concerns the crystallization of solids in a liquid environment. It covers industrial processes of synthesis and purification of solid substances and changes in particle properties. The reactors in which crystallization occurs are used in many branches of the economy, including: chemical, food [9], metallurgy and waste utilization [27]. One of the monitoring systems tasks of such processes is to provide precise information on the quantity, size and location of crystals formed in the liquid in real time. The second type of reaction relates to the gas phase and the liquid phase. Such processes type are used, inter alia, in the production of biogas. Physicochemical fermentation reactors are a key element of biogas installations. Methane fermentation of organic waste takes place inside these reactors. The correct operation of technical systems is one of the crucial conditions for obtaining an adequate level of reliability of industrial processes [10]. There are two main reasons to monitor the state of dynamic processes. The first one is the detection of impending failures [11] which RymARczyk T, kłosowski G. innovative methods of neural reconstruction for tomographic images in maintenance of tank industrial reactors. Eksploatacja i Niezawodnosc – maintenance and Reliability 2019; 21 (2): 261–267, http://dx.doi.org/10.17531/ein.2019.2.10.
许多化学工程产品都是通过使用化学反应器发挥关键作用的工艺线来生产的。化学反应器是一种容器，适于进行在其内部发生的反应。工业罐式反应器的目的是保证化工过程的最优经济参数[18]。它可以通过适当的反应堆设计和巧妙地重叠发生在反应堆内的三种类型的子过程，即质量、动量和热量的传递来实现。通过这种方式，过程控制可以基于动态选择的参数，如:混合强度，温度，压力，基材比例等。所提出的研究包括在固体和液体以及气体和液体之间发生反应的反应器。罐式反应器示意图如图1所示。第一类反应涉及固体在液体环境中的结晶。它涵盖了固体物质的合成和提纯的工业过程以及颗粒性质的变化。发生结晶的反应器用于许多经济部门，包括:化工、食品[9]、冶金和废物利用[27]。这种过程的监测系统任务之一是实时提供有关液体中形成的晶体的数量、大小和位置的精确信息。第二种类型的反应涉及气相和液相。除其他外，这种过程类型用于生产沼气。理化发酵反应器是沼气装置的关键部件。有机废物的甲烷发酵在这些反应器中进行。技术系统的正确运行是工业过程获得足够可靠性水平的关键条件之一[10]。监视动态流程的状态有两个主要原因。第一个是即将发生故障的检测[11]，其中RymARczyk T, kłosowski G.基于层析图像的神经重构创新方法用于储罐工业反应器的维护。Eksploatacja i Niezawodnosc -维护和可靠性2019;21 (2): 261-267, http://dx.doi.org/10.17531/ein.2019.2.10。
{"title":"Innovative methods of neural reconstruction for tomographic images in maintenance of tank industrial reactors","authors":"T. Rymarczyk, G. Kłosowski","doi":"10.17531/ein.2019.2.10","DOIUrl":"https://doi.org/10.17531/ein.2019.2.10","url":null,"abstract":"Many chemical engineering products are created as a result of processes carried out using technological lines in which chemical reactors play a key role. A chemical reactor is a vessel adapted to carry out reactions taking place inside it. The purpose of industrial tank reactors is to ensure optimal economic parameters of chemical processes [18]. It can be achieved by the appropriate reactor design and by the skillful overlap of the three types of sub-processes occurring inside the reactor, namely the transfer of mass, momentum and heat. In this way, process control can be based on a dynamic selection of parameters such as: mixing intensity, temperature, pressure, substrate ratios and others. The presented research included reactors in which reactions take place between solid and liquid as well as gas and liquid. The tank reactor diagram is shown in Fig. 1. The first type of reaction concerns the crystallization of solids in a liquid environment. It covers industrial processes of synthesis and purification of solid substances and changes in particle properties. The reactors in which crystallization occurs are used in many branches of the economy, including: chemical, food [9], metallurgy and waste utilization [27]. One of the monitoring systems tasks of such processes is to provide precise information on the quantity, size and location of crystals formed in the liquid in real time. The second type of reaction relates to the gas phase and the liquid phase. Such processes type are used, inter alia, in the production of biogas. Physicochemical fermentation reactors are a key element of biogas installations. Methane fermentation of organic waste takes place inside these reactors. The correct operation of technical systems is one of the crucial conditions for obtaining an adequate level of reliability of industrial processes [10]. There are two main reasons to monitor the state of dynamic processes. The first one is the detection of impending failures [11] which RymARczyk T, kłosowski G. innovative methods of neural reconstruction for tomographic images in maintenance of tank industrial reactors. Eksploatacja i Niezawodnosc – maintenance and Reliability 2019; 21 (2): 261–267, http://dx.doi.org/10.17531/ein.2019.2.10.","PeriodicalId":309533,"journal":{"name":"Ekspolatacja i Niezawodnosc - Maintenance and Reliability","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127218120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maintenance is one of the largest expenditures for the urban transport companies together with fuel (or energy) costs and drivers (personnel) [16], but is the most important one from the view of controllability, attending that fuel and labour costs are more externally driven (crude prices volatility, taxes, personnel policies and salaries, etc.). A proper maintenance policy, managerial processes and planning and optimization of maintenance decisions, scheduling and execution of work can lead to reduce costs, improve vehicle effectiveness, reliability and performance. Consequently, maintenance function is therefore vital for sustainable performance of any urban transport fleet. Attending the responsibility of ensuring that urban fleet achieves the expected performance, maintenance managers requires a tracking system for maintenance operations performance and results [3, 6, 20, 21]. Furthermore, it is in the interest of maintenance managers to know the relationship between the input of the maintenance process and the outcome in terms of total contribution to vehicle fleet performance and strategic objectives. The measurement of maintenance performance is indeed an essential requirement for any industry of today. This tracking action can be done through development and implementation of a proper and accurate performance measurement system and indicators that are able to quantify important elements of maintenance function performance [5, 15]. Moreover, without having a formal measurement system for maintenance performance, it is difficult to control, plan and improve the maintenance process and consequently can be considered that tracking the performance operations must be a key management issue in any industrial organization. In summary, a proper maintenance performance measurement system shall contribute to: Assess the maintenance function to the strategic company tar• gets. Detect the strengths and weaknesses on the maintenance strat• egy applied. Using quantitative and qualitative data for helping to define and • stablish a continuous improvement process for maintenance. Let us to apply a maintenance benchmarking analysis within and • outside the business related with urban fleet transport.
{"title":"Maintenance management balanced scorecard approach for urban transport fleets","authors":"V. Macián, B. Tormos, J. Herrero","doi":"10.17531/ein.2019.2.6","DOIUrl":"https://doi.org/10.17531/ein.2019.2.6","url":null,"abstract":"Maintenance is one of the largest expenditures for the urban transport companies together with fuel (or energy) costs and drivers (personnel) [16], but is the most important one from the view of controllability, attending that fuel and labour costs are more externally driven (crude prices volatility, taxes, personnel policies and salaries, etc.). A proper maintenance policy, managerial processes and planning and optimization of maintenance decisions, scheduling and execution of work can lead to reduce costs, improve vehicle effectiveness, reliability and performance. Consequently, maintenance function is therefore vital for sustainable performance of any urban transport fleet. Attending the responsibility of ensuring that urban fleet achieves the expected performance, maintenance managers requires a tracking system for maintenance operations performance and results [3, 6, 20, 21]. Furthermore, it is in the interest of maintenance managers to know the relationship between the input of the maintenance process and the outcome in terms of total contribution to vehicle fleet performance and strategic objectives. The measurement of maintenance performance is indeed an essential requirement for any industry of today. This tracking action can be done through development and implementation of a proper and accurate performance measurement system and indicators that are able to quantify important elements of maintenance function performance [5, 15]. Moreover, without having a formal measurement system for maintenance performance, it is difficult to control, plan and improve the maintenance process and consequently can be considered that tracking the performance operations must be a key management issue in any industrial organization. In summary, a proper maintenance performance measurement system shall contribute to: Assess the maintenance function to the strategic company tar• gets. Detect the strengths and weaknesses on the maintenance strat• egy applied. Using quantitative and qualitative data for helping to define and • stablish a continuous improvement process for maintenance. Let us to apply a maintenance benchmarking analysis within and • outside the business related with urban fleet transport.","PeriodicalId":309533,"journal":{"name":"Ekspolatacja i Niezawodnosc - Maintenance and Reliability","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115034836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A mathematical model of a forest crane that is suitable for dynamics analysis of its operation cycle is presented in this paper. The flexibility of the operator’s seat, drives and supports is taken into account. Joint coordinates are applied to describe the motion of the links together with the homogeneous transformations technique. Lagrange equations of the second order are used when deriving the equations of motions. Joint forces and torques are determined based on recursive Newton-Euler algorithms. These joint forces are then used in the LuGre friction model, which allows to calculate the friction coefficients and friction forces. Numerical analyses performed here show the influence of various friction forces on the vibration level as perceived by the operator of the crane. The level of discomfort is discussed based on standards commonly used in the vehicle and transportation industry for evaluations of vibration comfort.
{"title":"The influence of the friction phenomenon on a forest crane operator’s level of discomfort","authors":"A. Urbaś, M. Szczotka","doi":"10.17531/ein.2019.2.3","DOIUrl":"https://doi.org/10.17531/ein.2019.2.3","url":null,"abstract":"A mathematical model of a forest crane that is suitable for dynamics analysis of its operation cycle is presented in this paper. The flexibility of the operator’s seat, drives and supports is taken into account. Joint coordinates are applied to describe the motion of the links together with the homogeneous transformations technique. Lagrange equations of the second order are used when deriving the equations of motions. Joint forces and torques are determined based on recursive Newton-Euler algorithms. These joint forces are then used in the LuGre friction model, which allows to calculate the friction coefficients and friction forces. Numerical analyses performed here show the influence of various friction forces on the vibration level as perceived by the operator of the crane. The level of discomfort is discussed based on standards commonly used in the vehicle and transportation industry for evaluations of vibration comfort.","PeriodicalId":309533,"journal":{"name":"Ekspolatacja i Niezawodnosc - Maintenance and Reliability","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131466162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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