Development of a risk-based maintenance (RBM) strategy for a power-generating plant

The unexpected failures, the down time associated with such failures, the loss of production and, the higher maintenance costs are major problems in any process plant. Risk-based maintenance (RBM) approach helps in designing an alternative strategy to minimize the risk resulting from breakdowns or failures. Adapting a risk-based maintenance strategy is essential in developing cost-effective maintenance policies.The RBM methodology is comprised of four modules: identification of the scope, risk assessment, risk evaluation, and maintenance planning. Using this methodology, one is able to estimate risk caused by the unexpected failure as a function of the probability and the consequence of failure. Critical equipment can be identified based on the level of risk and a pre-selected acceptable level of risk. Maintenance of equipment is prioritized based on the risk, which helps in reducing the overall risk of the plant.The case study of a power-generating unit in the Holyrood thermal power generation plant is used to illustrate the methodology. Results indicate that the methodology is successful in identifying the critical equipment and in reducing the risk of resulting from the failure of the equipment. Risk reduction is achieved through the adoption of a maintenance plan which not only increases the reliability of the equipment but also reduces the cost of maintenance including the cost of failure.     

基于巡检的高速公路桥梁安全监测与维护研究

针对高速公路桥梁安全评价与维护的需要,在对现行高速公路桥梁安全监测、数据处理方法分析的基础上,应用设备状态监测原理,提出高速公路桥梁安全监测及安全趋势预测的方法。根据我国目前公路桥梁养护技术规范、高速公路桥梁养护运行模式,构建由人、物、理、程四部分组成的基于巡检的高速公路桥梁安全监测与维护体系,该体系实施过程分为准备、巡检、分析和维护4个阶段,即,在不影响高速公路桥梁正常运营下,通过巡检获取桥梁关键部位的状态参数并进行分析和评价桥梁状态,由专家系统或专家评价桥梁病害类型和维护方案。该体系还可对桥梁安全状态进行预判,满足高速公路桥梁预防性养护的需求,其实施将有助于提高高速公路桥梁的管理与维护水平。     

Risk-based maintenance policy selection using AHP and goal programming

Maintenance policy selection is a multiple criteria decision making. The criteria often considered are cost and reliability of maintenance. There has been a growing interest in using risk of accidents as a criterion for maintenance selection. This paper presents an approach of maintenance selection based on risk of equipment failure and cost of maintenance. Analytic hierarchy process (AHP) and goal programming (GP) are used for maintenance policy selection. A case study in a benzene extraction unit of a chemical plant was done. The AHP results show that considering risk as a criterion, condition based maintenance (CBM) is a preferred policy over time-based maintenance (TBM) as CBM has better risk reduction capability than TBM. Similarly, considering cost as a criterion, corrective maintenance (CM) is preferred. However, considering both risk and cost as multiple criteria, the AHP–GP results show that CBM is a preferred approach for high-risk equipment and CM for low risk equipment.     

Research and application of risk and condition based maintenance task optimization technology in an oil transfer station

Oil transfer stations of PetroChina mostly scatter in Gobi, mountain areas or other sparsely populated areas, inconvenient transportation and absent professional engineers often delay the best time to repair the machines. Time-or interval-based maintenance (TBM) accounts for almost 100%, while, On-condition maintenance and other proactive maintenance are seldom adopted. TBM not only can't prevent happens of equipment fault but also cause the waste of the maintenance resource. In order to allocate maintenance resources reasonably, ascertain the minimum preventive maintenance requirement, ensure the reliability, availability and safety, this paper carries out a research on Risk and Condition Based Maintenance (RCBM) task optimization technology. Utilizing the internet of things (IOT), real-time database, signal-processing, Gray Neural Network, probability statistical analysis and service oriented architecture (SOA) technology, a Risk and Condition Based Indicator Decision-making System (RCBIDS) is built. RCBIDS integrates RCM, condition monitoring system (CMS), key performance management module, file management module, fault and defect management module, maintenance management module together, which aims to realize remote condition monitoring, maintenance technical support services (TSS), quantitative maintenance decision-making, and to ensure the Reliability, Availability, Maintainability and Safety (RAMS). The Predictive Maintenance Indicator model, reliability prediction model and Key Performance Indicator (KPI) model, which are embedded in the RCBIDS, are constructed separately. An engineering case shows that the risk and condition based maintenance task optimization technology can be used to optimize maintenance content and maintenance period, to minimize maintenance deficiencies and maintenance surplus, and to prolong the lifespan of equipment.     

A framework to estimate the risk-based shutdown interval for a processing plant

Petrochemical plants and refineries consist of hundreds of pieces of complex equipment and machinery that run under rigorous operating conditions and are subjected to deterioration over time due to aging, wear, corrosion, erosion, fatigue and other reasons. These devices operate under extreme operating pressures and temperatures, and any failure may result in huge financial consequences for the operating company. To minimize the risk and to maintain operational reliability and availability, companies adopt various maintenance strategies. Shutdown or turnaround maintenance is one such strategy. In general, shutdown for inspection and maintenance is based on the original equipment manufacturer's (OEM) suggested recommended periods. However, this may not be the most optimum strategy given that operating conditions may vary significantly from company to company.The framework proposed in this work estimates the risk-based shutdown interval for inspection and maintenance. It provides a tool for maintenance planning and decision making by considering the probability of the equipment or system for failure and the likely consequences that may follow. The novel risk-based approach is compared with the conventional fixed interval approach. This former approach, characterized as it is by optimized inspection, maintenance and risk management, leads to extended intervals between shutdowns. The result is the increase in production and the consequent income of millions of dollars.The proposed framework is a cost effective way to minimize the overall financial risk for asset inspection and maintenance while fulfilling safety and availability requirements.     

基于物联网技术的设备状态维修安全管理研究

随着物联网(IOT)技术的不断发展,状态维修(CBM)理论逐步运用于设备安全管理中。通过构建基于物联网技术的设备状态维修安全管理体系,建立CBM预测决策模型,并通过设备轴承状态维修的例证来说明模型的可用性。结果表明:设备实现物联网后,基于物联网技术的设备状态维修安全管理是科学可行的,便于设备的维修管理,提高设备的安全工作寿命。     

民航机务维修系统安全风险监测

从人的因素、飞机的因素、环境因素和管理因素4方面分析了民航机务维修系统安全风险影响因素,结合专家调查意见建立了机务维修系统安全风险监测指标体系,并给出各个指标的含义及其衡量方法。根据机务维修系统安全风险指标及其数据特点,建立了行业机务维修系统安全风险模糊综合评价模型,并进行实例分析。结果表明,采用笔者建立的指标体系和风险模型可以方便地进行机务维修系统的安全风险评价和预警,从而找出主要的安全风险影响因素,为采取安全风险管理措施提供依据。     

煤矿安全生产监控集成系统研究

煤矿安全生产监控包括环境信息的监测和生产设备状态的监控,本文分析了我国煤矿安全监控系统研究与应用的现状,提出了一种煤矿安全生产监控集成系统的体系结构。详细介绍了该结构各层次的特点和功能,研究了基于该结构的系统层次和软件体系结构。该结构将煤矿环境灾难监测、生产设备运行监控等多任务系统集成为一个综合系统,便于煤矿的安全监测、生产组织和管理,同时,系统具有很好的组网灵活性、开放性和扩展性。     

“自由落体”游乐设备直流电机故障分析

创新是大型游乐设施占领市场的核心竞争力,但创新也容易引发各类问题及不确定性,特别是涉及游乐设备可维护性方面,更容易在创新过程中忽视。本文以国外设备供应商生产的“自由落体”游乐设备的故障入手,从研究直流电机故障机理、维修方案以及设计维保建议等几个方面,提出提升直流电机可维护性的举措,主张行业的设计人员不但要聚焦大型游乐设施的趣味性,也要更多关注如何提高大型游乐设施的可靠性、可维护性。     

Opportunistic predictive maintenance for complex multi-component systems based on DBN-HAZOP model

Predictive maintenance (PdM) focuses on failure prediction in order to prevent failure in advance and offer sufficient information to improve inherent safety and maintenance planning. A novel opportunistic predictive maintenance-decision (OPM) method integrating of machinery prognostic and opportunistic maintenance model is proposed in this paper to indicate the optimal maintenance time with minimal cost and safety constrains. DBN-HAZOP model quantifies hazard and operability analysis by dynamic Bayesian networks to provide prospective degradation trends of each component and the overall system for maintenance decision making. It is developed by integrating the prior knowledge of the interactions and dependencies among components and also the external environment, while the online condition monitoring data which is further to update the parameters of the model. Based on the future degradation trends given by DBN-HAZOP model, a local optimal proactive maintenance practice can be determined for each component by minimizing the expected maintenance cost per time unit. Understanding that for a complex system, whenever one of the components stops to perform a predictive maintenance action, the whole complex system must be stopped, at this moment, PdM opportunities arise for the other degraded components in the system at a reduced additional cost. Therefore, this paper further proposes an opportunistic PdM strategy for global cost optimization of predictive maintenance for the whole system, which considers failure probabilities, repair costs, down time cost and set-up cost. Case studies are given throughout to show how this approach works, and the sensitivity of the results to some of the driving cost parameters has also been examined.     

煤矿安监系统数据通信可靠性的研究

煤矿安全生产监控系统的通信网络可归纳为单分站单设备、单分站双设备、双分站单设备和双分站双设备几种组网模式,通过对其任务可靠性和基本可靠性进行比较分析,综合考虑任务完成概率和维护成本两方面的要求,提出了双分站,局部(高故障点处)双设备的组网模式,以期有效提高通信网络的系统可靠性。     

煤矿安全生产协同监控系统分析与设计

针对煤矿安全生产多套监控系统并存的现状,通过将煤矿系统模块化,形成了基于安全信息管理数据库的安全生产协同监控系统.该系统能够以工作场所为单位综合分析各类安全信息,协调各部门的安全生产工作,为其提供参考,同时节约资源,减少操作人员,提高危险源辨识准确性,预测事故并将其消灭在萌芽状态,形成闭环安全管理.     

生物质固体成型燃料技术及设备研究进展

介绍了国内外生物质固体成型燃料技术与产业及成型机发展现状,综述了生物质固体燃料成犁机的几种类型及特点,对各种成型设备的性能和应用进行了比较,并针对目前国内生物质固体成型燃料技术及没备存在的问题,提出了我国生物质固体成型燃料及设备产业化的发展方向.     

基于安全性的特种设备维修策略研究

针对我国目前安全生产形势，对特种设备使用与维修应予以特别重视，分析了特种设备维修管理现状及存在的问题，阐述了特种设备维修中的关键问题并提出了解决这些关键问题维修策略；利用计算机辅助故障树分析，找同特种设备维修重点；以特种设备的安全运行为目标；提出了合理维修周期求解模型；设计并实现了特种设备维修管理信息系统，将故障树分析和维修周期求解融入其中，实现了特种设备维修决策的科学化和规范化。实践证明，该信息系统实现了提出的维修策略，对提高特种设备的安全性和经济性有较大的实用价值。     

An ontology-based framework for process monitoring and maintenance in petroleum plant

In production plants, monitoring and maintaining industrial processes and emergency shutdowns are not straightforward tasks due to the large number of events and alarms which are triggered during the plant shutdown process. It is also vitally important to provide decision support to stakeholders for efficient and effective monitoring and maintenance of production process. This paper presents a novel framework and design to enhance maintenance decisions based on the knowledge gathered through the process of monitoring. This monitoring process is based on signals which are triggered during the plant safety shutdown process. We have designed and implemented a framework using an ontology and business rules to define the logical structure and operation of the petroleum plant with the objective of monitoring the cause and effect of the petroleum plant shutdown process. To enhance maintenance decisions, we have extended the ontology and the framework to ensure that decision makers have sufficient information to make the right decision at the right time. The proposed extended framework is designed, implemented and evaluated using an example petroleum production plant as a case study.     

基于动态信息技术的设备主动维护预知平台的设计

石化企业规模大、设备种类繁多且分布广,为规范设备的管理流程、提高设备的管理水平及设备可靠性,提高企业的经济效益和安全性,建立了基于Oracle数据库与RBI和RCM技术的设备预知维护信息平台,并结合RBI及RCM技术信息输入与安全评价方法,实现设备的故障预知及维护规范。该平台与石化的生产运行管理相结合,可实现设备的信息化管理,在及时排除设备故障隐患的同时,保障设备的正常运行,为改善企业生产安全现状和提高设备管理水平,提供了新的方法。     

污水处理厂设备维护管理优化研究

以JL污水处理厂设备管理优化过程为例,充分吸取LCC,TPM中的先进思想,以设备运行可靠性及设备维护经济性为追求目标,建立了设备管理优化体系。流程体系上,通过建立作业指导文件,建立标准化维修程序,对于操作过程及时进行记录,建立可视化、可追溯的管理方法;指标体系上,根据设备重要性及运行状况,确定设备风险指数,分级管理;建立控制指标,并动态调整;管控体系上,建立设备“户口”,对设备的维护、保养、使用等信息进行全面登记;考核设备维护的全面性、及时性、可靠性、合规性;重视设备维护的预计与预警;技术体系上,通过设备监测仪器的使用,对设备运行状况定量化。通过不断推进设备预防性维护工作,设备完好率不断提升,仪表完好率从2016年的97.34%,96.55%水平,分别提升至99.08%,98.72%;维护费用也保持在较低水平,检修费与资产比例在实施的前两年分别降至1.49%,0.85%,实现了污水处理厂节能降耗及运行可靠性的强化。     

工矿企业实施设备、设施本质安全化探讨

分析了企业生产过程中,设备、设施本质安全化的状况,认为企业安全工作的根本出路在于设备、设施本质安全化.提出了通过加强企业领导安全意识,提高生产系统的安全投入,在建设项目的设施过程中力争提高设备设施的本质安全化水平,抓好新建、改建、扩建工程项目的"三同时"管理和安全评价,生产单位通过认真做好生产过程中的维护管理等途径提高设备、设施本质安全化.     

基于知识推理的发电企业设备风险管理应用研究

基于发电企业设备自身的特点及工作人员对风险知识认知的局限性,有必要分析发电企业设备在运行、检修中潜在的风险.分析了设备风险知识与风险管理的关系,并以发电企业各类大型设备中应用最广泛的电动机为例,解决了电动机风险知识的表达及推理问题,为实现基于知识的设备风险管理提供了一种思路,对指导发电企业的设备日常维护、巡检以及状态监测、避免不必要的损失有着积极的意义.