以可靠性为中心的维修方法及其在隧道中的应用

本文针对目前隧道监控维修状况及存在的问题,提出以可靠性为中心的维修(RCM)作为维修理念,并将其引入到隧道管理中,对隧道设备的故障模式及可靠性进行分析,并对RCM方法在隧道监控维修中的应用做了初步研究。最后通过案例说明,隧道采用RCM方法可有效降低维修费用,具有一定的经济效益和社会效益。     

浅探RCM在高速公路机电养护中的运用

1RCM的产生和发展 以可靠性为中心的维修,简称RCM（ReliabilityCenteredMaintenance）．是目前国际上流行的、用以确定设备预防性维修工作、优化维修制度的一种系统工程方法,也是发达国家军队及工业部门制定装备和设备预防性维修大纲的首选方法。     

维修管理模式对制造企业质量控制影响的实证研究

可靠的设备预防维修水平和卓越的产品质量保证能力是保障产品过程质量的关键,现有多数研究集中在质量管理模式与企业绩效的关系分析。在对过程质量控制、设备维修管理评述的基础上,探讨了设备维修管理模式与维修绩效及过程质量控制绩效间的关系。以国内制造企业的连续生产方式为研究对象,运用结构方程模型剖析了RCM、TPM、设备采购管理与和设备维修绩效、过程质量控制绩效的路径关系,发现基础维修管理活动对维修绩效有间接影响,RCM、TPM对设备维修绩效有显著影响,路径系数分别为0.346、0.717,设备维修绩效对过程质量控制绩效的影响显著,路径系数为0922。证明制造企业为提升产品质量,需要完善其设备预防维修系统。     

RCM与风险分析技术的研究和应用

采用传统的以可靠性为中心的维修(RCM)与风险分析相结合的理论,对国内某炼油厂的常减压装置动设备进行了分析,提供了基于风险的RCM技术解决方案.论文中的分析方法既满足了对动设备开展可靠性分析的技术诉求,又继承了目前国内正在广泛开展的基于风险的管理(RBM)理念.     

基于RCM的港口机械关键设备的维修决策

以港口起重机械为对象,在为振华港机建立的以可靠性为中心的维修决策流程框架下,对所涉及的维修方式进行研究优化.结合故障率调整因子,探索了按有效度最大的原则确定港口机械的最佳预防维修周期的算法;基于P-F间隔,提出了基于RCM的状态维修检测周期算法.最后,开发了可靠性维护系统,通过程序开发,实现各项功能模块.为企业的设备维护提供科学的决策支持.     

以可靠性为中心的维修的经济效益评估模型

以可靠性为中心的维修(Reliability—centered Maintenance,RCM)的经济效益评估模型是国内外首次系统、全面、简单、有效评估核电站维修优化成果的方法。本文从RCM经济效益评估内容和分类着手,详细介绍了分析后取消项目、增加项目显性及隐性经济效益评估模型,并结合大亚湾核电站现状进行了实证应用与分析。     

浅谈地铁综合监控系统的发展方向

随着自动化集成技术的成熟,国内的地铁项目逐渐开始通过综合监控系统建立统一的软硬件平台,实现资源共享、互联互通、设备集中管理和维护,同时还可对子系统进行故障监测,并为紧急情况下事件的处理提供全面、及时的信息和控制能力,提高地铁整体运营调度管理水平,从而推动地铁自动化整体水平迈上了一个新的台阶。     

基于改进的TOPSIS的设备重要度分析

一个工业设备通常由多个子系统组成，各子系统在系统中的重要程度不同，导致了设计阶段的可靠性分配、运行阶段的检测水平以及维修方式的决策等都须以其重要度为基础。采用改进的TOPSIS确定系统中每个子系统的重要度，以满足实际需求。此方法在根据信息熵法求取各属性权重的基础上采用TOPSIS计算各子系统的重要度。将其应用到塑料挤出机的重要度分析中，结果表明，该方法对设备重要度的确定是有效的和实用的。     

地铁通信系统集成及工程实施探究

地铁通信系统的完善是促进地铁可靠运行的重要支撑,是促使地铁资源共享的重要路径。地铁通信系统所囊括的子系统众多,做好其工程建设和实施就显得极为重要。基于此,本文就地铁通信系统集成及工程实施进行分析与研究,希望可以为地铁通信系统的更好建设提供借鉴。     

基于RCM理论的B超设备常见故障诊断方法研究

B超是医疗卫生单位中主流医学影像设备,在临床应用上具有不可替代性,但目前国内的医疗B超采购大多被国外厂商垄断,不仅影响到设备的购买市场,还影响到了B超的维修保养行业。为解决这问题,将可靠性为中心的维修RCM理论引入B超维修与管理中,并通过归纳常见的故障实例分析,为超声设备的故障分析与维护提供技术参考,对医疗设备的售后服务行业健康有序的发展具有重要的促进作用。     

Reliability centered maintenance

Reliability centered maintenance (RCM) is a method for maintenance planning developed within the aircraft industry and later adapted to several other industries and military branches. This paper presents a structured approach to RCM, and discusses the various steps in the approach. The RCM method provides a framework for utilizing operating experience in a more systematic way. The requirements for reliability models and data are therefore highlighted. The gap between maintenance practitioners and scientists working with maintenance optimization models is discussed, together with some future challenges for RCM.     

A framework for reliability and risk centered maintenance

Reliability centered maintenance (RCM) is a well-established analysis method for preventive maintenance planning. As its name indicates, reliability is the main point of reference for the planning, but consequences of failures are also assessed. However, uncertainties and risk are to a limited extent addressed by the RCM method, and in this paper we suggest an extension of the RCM to reliability and risk centered maintenance (RRCM) by also considering risk as the reference for the analysis in addition to reliability. A broad perspective on risk is adopted where uncertainties are the main component of risk in addition to possible events and associated consequences. A case from the offshore oil and gas industry is presented to illustrate and discuss the suggested approach.     

Discrete differential operators on irregular nodes (DDIN)

A previous research made an integral mathematical contribution for obtaining local function interpolation using neighboring nodal values of the solution function. Subsequent researchers developed mesh‐free methods for Finite Element Method (FEM). This principle can also be used to obtain discrete differential operators on irregular nodes. They may be successfully applied to Finite Difference method, Moving Particle Semi‐implicit (MPS) method and Random Collocation Method (RCM). In this paper, we obtain discrete differential operators on irregular nodes and successfully apply them to solve differential equations using the RCM. We also discuss mathematical aspects of the MPS method. Copyright © 2011 John Wiley & Sons, Ltd.     

Maintenance strategy for tilting table of rolling mill based on reliability considerations

Reliability centred maintenance (RCM) is a new strategic framework for ensuring that any asset continues to perform, as its users want it to perform. RCM is a process used to determine the maintenance requirement of any physical asset in its operating context. RCM process entails asking seven questions about each of the selected assets. It makes use of two documents namely, RCM information worksheet and RCM decision worksheet. RCM decision diagram integrates all the decision processes into a single strategic framework. RCM concept developed by US commercial airlines industry has been successfully implemented by Military, Navy, Nuclear power plants, electric power generation and distribution undertakings and several other sectors. These projects have been carried out in the United Kingdom, The Republic of Ireland, the United States, Hong Kong, Australia, Spain and Singapore. The fact that people has enthusiastically received RCM at all levels and has enabled users to achieve some remarkable successes in all of these countries, suggests that it can be universally employed. Literature review indicates that RCM approach is not conventionally applied in process industries in India. Presently, predictive maintenance (PDM) approach along with conventional preventive maintenance is used in continuous/process industries. This approach if implemented in totality will increase the production cost to a large degree and make the production uneconomical. Similarly breakdown maintenance (BDM) approach cannot be applied in such industries as each breakdown involves huge costs. RCM approach is a compromise between PDM and BDM approach for optimising the cost and ensuring the availability of machine.The RCM approach has been applied to the tilting table system of rolling mill for the research work reported in this paper. In the present study, preventive maintenance tasks suggested for power transmission subsystem, guiding and transportation subsystem and hydraulic subsystem in tilting tables are 14 scheduled on-condition tasks, 10 scheduled on-restoration tasks, seven scheduled discard task. Whereas for 14 failure modes no scheduled maintenance has been proposed. Existing maintenance schedule for tilting tables indicates the maintenance action as and when required. Hence RCM based schedule specifies that additional preventive maintenance tasks need to be executed as compared to none initially. Cost incurred for this can be offset from the savings accrued from reduction in loss of production due to repetitive breakdowns. The methodology of RCM adopted in western industries cannot be applied as it is to Indian industries because of labour oriented nature, partially computerised information systems, non-availability of the information about cost of loss of production due to breakdown and age-reliability pattern of equipment, insufficient maintenance database. These problems can be overcome by development of sound MMIS, formulation of RCM review group and imparting suitable training to acquire the relevant skills in RCM. Thus RCM methodology can be applied to Indian industry for reduction of breakdowns as well as optimisation of preventive maintenance cost. This can further boost up the prospects of Indian industry to offer the products at globally competitive prices.     

Age-related maintenance versus reliability centred maintenance: a case study on aero-engines

Reliability Centred Maintenance (RCM) is a procedure carried out as part of the logistic support analysis (LSA) process and is described in the US Department of Defence Military Standards (Mil Std 2173). RCM allows logisticians the opportunity to determine the best maintenance policy for each component within a system. However, the only data that are available to carryout RCM using Mil Std 2173 are of MTBF. This implies that all the necessary mathematical models need to be based on the exponential distribution. This is a serious drawback to the whole concept of RCM as the exponential distribution cannot be used to model items that fail due to wear, or any other mode that is related to their age. In this paper, a new approach to RCM is proposed using the concepts of soft life and hard life to optimise the total maintenance cost. For simplicity, only one mode of failure is considered for each component. However, the model can be readily applied to multiple failure modes. The proposed model is applied to find the optimal maintenance policies in the case of military aero-engines using Monte Carlo simulation. The case study shows a potential benefit from setting soft lives on relatively cheap components that can cause expensive, unplanned engine rejections.     

A Fast and Self-Acting Release-Caging-Mechanism for Actively Driven Drop Tower Systems

Today’s and future scientific research programs ask for high quality microgravity conditions of 10^?6 g on ground combined with high repetition rates of 100 flights per day or more. Accordingly, a new type of drop tower, the GraviTower Bremen, (GTB), has been suggested and is currently under development. As a first stage of development, a GTB-Prototype (GTB-Pro) has been designed which uses an active rope drive to accelerate a slider/drag shield and an experiment therein on a vertical parabola. During the free fall phase, the experiment is decoupled from the slider by a self-acting Release-Caging-Mechanism (RCM). Our prototype will provide 2.5 s of microgravity for experiments of up to 500 kg for at least 100 times per day. In this article, the final concept of the engineering of the active rope drive and the RCM are presented in detail. Based on extensive simulations aiming at an optimization of the whole system we developed a hydraulic rope drive system with minimized vibrational amplitude and low number of eigenfrequencies. The RCM achieves a very fast (≤ 0.1 s) self-acting release of the experiment from the slider by making use of the dynamics of the hydraulic rope drive. Furthermore, passive hydraulic stop dampers in the RCM build a passive and self-acting recoupling mechanism. This system is optimized for a fast decoupling to compensate for the time limitation posed by the chosen drive technology. The simulations included a comparison of different drive technologies, physical effects like the Coriolis force, and the dynamics of the RCM system itself.     

Applying RCM in large scale systems: a case study with railway networks

In 2000, the European Union founded a project named ‘RAIL: Reliability centered maintenance approach for the infrastructure and logistics of railway operation’ aimed to study the application of Reliability centered maintenance (RCM) techniques to the railway infrastructure. In this paper, we present the results obtained into the RAIL project, including a RCM methodology adapted to large infrastructure networks and a RCM toolkit to perform the RCM analysis, including cost aspects and maintenance planning guidance. This paper addresses the problem of applying RCM to large scale railway infrastructure networks to achieve an efficient and effective maintenance concept. Railways use nowadays very traditional preventive maintenance (PM) techniques, relying mostly on ‘blind’ periodic inspection and the ‘know-how’ of maintenance staff. RCM was seen as a promising technique from the beginning of the RAIL project because of several factors. First, technical insights obtained were better than the existing, so that several maintenance processes could be revised and adjusted. Second, the interdisciplinary approach used to make the analysis was very enriching and very encouraging for maintenance staff consulted. Third, using the RCM structured approach allowed to achieve well-documented analysis and clear decision diagrams. Our methodology includes some new features to overcome the problems of RCM observed in other projects. As a whole, our methodology and Computerized Maintenance Management Systems have produced two short-term benefits: reduction of time and paperwork because databases and tools are accessible through Internet, and creation of a permanent, accurate, and better collection of information. It will also have some long-term benefits: better PM will increase equipment life and will help to reduce corrective maintenance costs; Production will increase as unscheduled downtime decreases; purchase costs of parts and materials will be reduced; more effective and up-to-date record of inventory/stores reports; and better knowledge of the systems to help the company to chose those systems with the best LCC. The results have been corroborated with the application of our methodology to signal equipment in several railway network sections, as shown in this paper. Because of the successful conclusion of the project, the Spanish railway company (RENFE) and the German railway company (DB A.G.), not only decided to adopt RCM to enhance PM, but they have started a large project to implement Total Preventive Maintenance relying on the implantation of the RCM methodology.     

Repair of experimental Achilles tenotomy with porcine renal capsule material in a rat model

Porcine small intestinal submucosa (SIS) is a collagenous acellular matrix which has found substantial utility as a tissue growth scaffold. In the present study, the utility of porcine renal capsule matrix (RCM) was compared to SIS in a rat Achilles tenotomy repair model. Groups of rats underwent surgical tenotomy followed by either no repair, repair with a SIS graft, or repair with a RCM graft. The weight-bearing ability of the manipulated limb was evaluated for 10 days following surgery using a subjective scale. Tenotomy sites sampled 28 days after surgery were numerically graded for degree of histologic change. There were no statistically significant differences between groups with respect to return to weight-bearing ability (p ≥ 0.05) or degree of histologic change (p ≥ 0.001); however, a non-significant trend suggested that rats treated with SIS or RCM experienced a faster return to limb function than untreated rats, and RCM-treated rats had slightly higher scores for degree of histologic change, suggesting a more rapid repair of the tenotomy site than in SIS-treated or untreated rats. The harvested tenotomy sites in all treatment groups were characterized by marked fibroplasia and presence of macrophages. Remnants of SIS surrounded by macrophages and multi-nucleated giant cells were still present in some rats, however remnants of RCM were not observed, suggesting more rapid incorporation of RCM. The results show that RCM is equivalent to SIS as a material for repair of Achilles tendon injury and merits further study in other tendon injury models.