This document discusses using control charts to guide maintenance policy selection. Specifically, it proposes using a time-based control chart (t-chart) to monitor the failure process of components. The t-chart would track the time between failures and use control limits to identify eight different maintenance policy zones. A case study applying this approach to an armored flexible conveyor in an underground coal mine in India is described to illustrate how the maintenance policy zones could inform maintenance decisions.
This document provides an overview of condition-based maintenance (CBM) and how to manage a CBM program. It defines CBM as maintenance performed after indicators show equipment is failing or performance is deteriorating. The benefits of CBM over planned maintenance are described as improved reliability, safety, lower costs, and increased readiness. Potential disadvantages like high costs and increased complexity are also outlined. The document discusses the evolution of maintenance from a run-to-failure approach to more proactive CBM. It provides examples of CBM tools and techniques including vibration monitoring and trend analysis. Finally, it emphasizes that CBM supports a safety management system by addressing problems before failures occur.
CBM Cost Benefit Analysis by Carl Byington - PHM Design, LLCCarl Byington
Carl Byington with PHM Design, LLC reviews some of the elements of CBM Cost Benefit Analysis. The analysis consider implementation and non recurring engineering cost as well as deferred, eliminated scheduled maintenance, reduced unscheduled maintenance, and operational cost savings drivers. Specific examples from aircraft, ground vehicle, and industrial applications are provided.
#phmdesign
https://phmdesign.com
CBM Requirements by Carl Byington - PHM Design, LLCCarl Byington
Carl Byington with PHM Design, LLC reviews:
Conceptual functional architecture:
Describes functions and functional interactions
Traces functions to capabilities or services desired in the COO
Conceptual physical architecture:
Allocates and describes the conceptual implementation of functions
Traces implementation to function
Activity Flows:
Identifies primary paths through the principal use-cases to meet the goals and interests of the stakeholders
Trades identify preferred path which, in turn, provides context for requirements derivation and operational thread development.
#phmdesign
https://phmdesign.com
Carl Byington is a consultant who advocates for condition-based maintenance (CBM), which involves monitoring equipment performance through sensors and performing maintenance only when data indicates a potential failure. CBM aims to decrease unnecessary maintenance costs while increasing operational readiness compared to traditional time-based maintenance. Implementing CBM requires predictive diagnostics using sensor data fusion to determine equipment health and predict remaining useful life. It is an emerging strategy enabled by advances in sensors, data processing, and machine learning techniques. The first step is identifying critical assets suitable for CBM monitoring.
The document discusses different types of machine maintenance. It defines maintenance as activities intended to retain or restore functionality. There are two main types of maintenance: planned and unplanned. Planned maintenance includes preventive, corrective, improvement, and predictive maintenance. The goals of maintenance are to maximize uptime and equipment life while minimizing costs. Proper maintenance is important for safety, productivity and profitability.
A complete guide on preparation, planning and execution of a computerized maintenance management system with examples and illustration of the program modules interaction and the way these programs operate.
Definition of RCM, principles and goals of RCM; Four major components of RCM: reactive maintenance, preventive maintenance, predictive testing and inspection and proactive maintenance; RCM strategies.
This document provides an overview of condition-based maintenance (CBM) and how to manage a CBM program. It defines CBM as maintenance performed after indicators show equipment is failing or performance is deteriorating. The benefits of CBM over planned maintenance are described as improved reliability, safety, lower costs, and increased readiness. Potential disadvantages like high costs and increased complexity are also outlined. The document discusses the evolution of maintenance from a run-to-failure approach to more proactive CBM. It provides examples of CBM tools and techniques including vibration monitoring and trend analysis. Finally, it emphasizes that CBM supports a safety management system by addressing problems before failures occur.
CBM Cost Benefit Analysis by Carl Byington - PHM Design, LLCCarl Byington
Carl Byington with PHM Design, LLC reviews some of the elements of CBM Cost Benefit Analysis. The analysis consider implementation and non recurring engineering cost as well as deferred, eliminated scheduled maintenance, reduced unscheduled maintenance, and operational cost savings drivers. Specific examples from aircraft, ground vehicle, and industrial applications are provided.
#phmdesign
https://phmdesign.com
CBM Requirements by Carl Byington - PHM Design, LLCCarl Byington
Carl Byington with PHM Design, LLC reviews:
Conceptual functional architecture:
Describes functions and functional interactions
Traces functions to capabilities or services desired in the COO
Conceptual physical architecture:
Allocates and describes the conceptual implementation of functions
Traces implementation to function
Activity Flows:
Identifies primary paths through the principal use-cases to meet the goals and interests of the stakeholders
Trades identify preferred path which, in turn, provides context for requirements derivation and operational thread development.
#phmdesign
https://phmdesign.com
Carl Byington is a consultant who advocates for condition-based maintenance (CBM), which involves monitoring equipment performance through sensors and performing maintenance only when data indicates a potential failure. CBM aims to decrease unnecessary maintenance costs while increasing operational readiness compared to traditional time-based maintenance. Implementing CBM requires predictive diagnostics using sensor data fusion to determine equipment health and predict remaining useful life. It is an emerging strategy enabled by advances in sensors, data processing, and machine learning techniques. The first step is identifying critical assets suitable for CBM monitoring.
The document discusses different types of machine maintenance. It defines maintenance as activities intended to retain or restore functionality. There are two main types of maintenance: planned and unplanned. Planned maintenance includes preventive, corrective, improvement, and predictive maintenance. The goals of maintenance are to maximize uptime and equipment life while minimizing costs. Proper maintenance is important for safety, productivity and profitability.
A complete guide on preparation, planning and execution of a computerized maintenance management system with examples and illustration of the program modules interaction and the way these programs operate.
Definition of RCM, principles and goals of RCM; Four major components of RCM: reactive maintenance, preventive maintenance, predictive testing and inspection and proactive maintenance; RCM strategies.
Reducing Maintenance Costs In A Tough Economic ClimateOMCS International
The document discusses reducing maintenance costs in a tough economic climate. It outlines different maintenance options like condition-based maintenance, fixed time replacement, and operate to fail. It provides examples of reviewing and optimizing maintenance programs to reduce costs at an aluminum smelter, chemical plant, and underground mining equipment. Suggestions are given to eliminate unnecessary tasks, maximize operator roles, switch to condition-or output-based servicing, and focus on the most expensive maintenance areas.
The document provides an introduction to predictive maintenance. It outlines the objectives of the course, which are to define predictive maintenance programs and various condition monitoring techniques, including vibration analysis, lubrication analysis, ultrasonic analysis, and thermographic analysis. The agenda covers topics such as predictive maintenance, maintenance planning, vibration analysis, and thermal analysis. The document then begins discussing predictive maintenance in more detail, defining preventative maintenance, predictive maintenance, and condition monitoring. It explores patterns of equipment failure and how to monitor equipment condition.
Definition of Preventive Maintenance, PM Elements, Plant Characteristics In Need of a PM Program, Principle for Selecting Items for PM, PM Measures, PM Models with examples
The document describes a case study applying reliability-centered maintenance (RCM) methodology to develop a maintenance plan for a steam-process plant in Egypt. The plant consists of a fire-tube boiler, feed-water pump, dryers, and process heater. A failure mode and effect analysis was conducted for critical equipment. The boiler and pump were found to be critical. An RCM-based maintenance program was developed that decreased labor costs by 25.8% and downtime costs by 80% compared to the plant's current maintenance.
The document discusses plans for implementing a preventive maintenance program at a residential life facility. It outlines preparations like gathering equipment data, labeling systems, and preparing equipment. It describes the maintenance management system that will be used to schedule tasks. Implementing preventive maintenance is expected to save significant time on tasks like filter changes. Challenges may include social and technical factors, but the benefits of preventive maintenance in reducing costs and downtime outweigh these challenges.
Maintenance and Operation Management-Emergency Management System YoungTae (Henry) Huh
This document provides an overview of maintenance and operation for an Emergency Management System (EMS) case study in Bangladesh. It describes the key components of an EMS including software, hardware, network architecture and users. It then covers various aspects of maintaining and operating the EMS such as defining maintenance and operations, the management process, necessary systems and tools, required organization and human resources, different phases and types of maintenance. It also discusses methods, procedures and checks for regular and special maintenance of the EMS.
Definition, types of corrective maintenance, steps and cycle;
Measures of corrective maintenance are: Mean Corrective Maintenance Time , Median Active Corrective Maintenance Time, Maximum Active Corrective Maintenance Time.
Then different models : a system that can either be in up (operating) or down (failed) state; a system that can either be operating normally or failed in two mutually exclusive failure modes; a system that can either be operating normally, operating in degradation mode, or failed completely; a two identical-unit redundant (parallel) system. At least one unit must operate normally for system success.
Preventive maintenance refers to regularly scheduled maintenance tasks that are intended to prevent equipment failures and unplanned downtime. It involves careful planning and scheduling of inspections and servicing before issues occur. Recommended standards help determine what maintenance is needed and how often based on the equipment type and operation. The benefits of preventive maintenance compared to reactive maintenance include cost savings of 12-18% from less downtime, repairs, and errors as well as prolonged equipment life.
The document discusses different types of maintenance activities. It defines maintenance and its objectives to keep equipment operational at minimum cost. It describes various types of maintenance including planned preventive maintenance to minimize breakdowns, and unplanned corrective maintenance after failures occur. Predictive maintenance uses condition monitoring to detect potential failures while preventive maintenance relies on routine inspections.
Simple Steps to Improve Your Maintenance ProgramTranscat
Presented by John Bernet of Fluke Corporation, Fluke and Transcat detail the benefits of a proactive maintenance program and how it compares to historical reactive, preventive, and predictive maintenance schedules.
The Future of Maintenance Management: 11 Trends Shaping Your Workplace and Ho...Jason Johnson
Join us as we explore eleven emerging trends in maintenance management and how, with the help of CMMS software, you can capture critical data for making good decisions to help your organization save time and money.
The document discusses maintenance management and provides definitions of key terms. It describes the evolution of maintenance from simply fixing equipment when it breaks to more modern approaches like reliability centered maintenance (RCM). The objectives of maintenance are to preserve asset functions and avoid failures. The functions of maintenance management include physical asset management, maintenance strategy determination, and planning and scheduling maintenance work. Different maintenance strategies like preventative maintenance and condition-based maintenance are also covered.
Reliability centered maintenance (RCM) integrates different maintenance strategies including reactive, preventive, predictive testing and inspection, and proactive maintenance. The goal of RCM is to maximize reliability and minimize maintenance costs and downtime. RCM involves analyzing systems to understand failures, prioritizing failures based on consequences, and determining the best strategy to address each failure. Common applications of RCM include the aviation, spacecraft, nuclear, and defense industries where minimizing downtime is critical.
It saves more then it costs....
Preventive maintenance and reactive maintenance are an extremely critical part of any fleet operations. By creating a Preventive Maintenance program to decrease the incidents of equipment arriving late for the PM’s they are due for, this program can be an integral part of cost savings and reduction of equipment downtime for repairs.
Hello Everyone!
This is the best ppt on 'Industrial Maintenance' that you can ever find. I tried to include all the topics related to the maintenance of industry. These notes will also be helpful from university exam point of view. Go through the whole ppt and leave a feedback in the comment box. Learn and Enjoy!
Thank You!
This document discusses how utilities are moving from traditional time-based maintenance to condition-based maintenance (CBM) by leveraging new technologies to optimize asset management. CBM utilizes data from inspections, testing, predictive maintenance technologies and online monitoring to determine the optimal maintenance strategy. The document outlines how utilities can better implement CBM by integrating their data management systems, which analyze condition monitoring data, with their work management systems, which plan and schedule maintenance work, to create a closed-loop process where data drives maintenance decisions and work orders. Automating data collection and integrating different data sources enables a more effective overall asset management strategy focused on CBM.
This document summarizes trends in maintenance management approaches over time. It discusses early approaches like breakdown maintenance from before 1950. It then outlines the development of preventive maintenance between 1950-1960, predictive maintenance between 1960-1970, condition-based maintenance, total productive maintenance between 1970-1985, and computerized maintenance management systems after 1985. The document provides examples of each approach and concludes that while new trends emerge, older approaches still have applicability depending on the situation.
How to set up a Preventive Maintenance ProgramSchoolDude
The document discusses the importance and best practices of implementing a preventive maintenance (PM) program. It outlines that PM programs can reduce emergency work orders by 25% and lower overall maintenance costs by performing cheaper scheduled maintenance. A successful PM program follows four steps: 1) determining PM schedules and plans, 2) assigning staff, 3) gaining management support, and 4) ongoing reporting and improvement. Regular maintenance can extend equipment lifespan, improve safety and energy efficiency, and lower long-term costs compared to deferred maintenance. The SchoolDude PMDirect software allows for automated PM work generation and performance tracking to help facilities teams successfully implement and monitor a PM program.
Este documento presenta una serie de ejercicios resueltos sobre análisis de circuitos eléctricos en serie, paralelo y mixtos. Inicia explicando la ley de Ohm y cómo calcular corriente, voltaje y resistencia en un circuito simple. Luego cubre temas como sumar resistencias en serie y paralelo, así como calcular voltaje y corriente total para circuitos con múltiples componentes. Finaliza con un ejemplo sobre un circuito mixto y los pasos para reducirlo a su resistencia equivalente.
Este documento describe cómo resolver un circuito eléctrico mixto con resistencias en serie y paralelo para encontrar las variables como voltaje, corriente y resistencia equivalente. Primero se calcula la resistencia equivalente de cada agrupación en paralelo, luego se trata el circuito completo como uno en serie. Finalmente, se analizan las corrientes y voltajes individuales en cada rama.
Reducing Maintenance Costs In A Tough Economic ClimateOMCS International
The document discusses reducing maintenance costs in a tough economic climate. It outlines different maintenance options like condition-based maintenance, fixed time replacement, and operate to fail. It provides examples of reviewing and optimizing maintenance programs to reduce costs at an aluminum smelter, chemical plant, and underground mining equipment. Suggestions are given to eliminate unnecessary tasks, maximize operator roles, switch to condition-or output-based servicing, and focus on the most expensive maintenance areas.
The document provides an introduction to predictive maintenance. It outlines the objectives of the course, which are to define predictive maintenance programs and various condition monitoring techniques, including vibration analysis, lubrication analysis, ultrasonic analysis, and thermographic analysis. The agenda covers topics such as predictive maintenance, maintenance planning, vibration analysis, and thermal analysis. The document then begins discussing predictive maintenance in more detail, defining preventative maintenance, predictive maintenance, and condition monitoring. It explores patterns of equipment failure and how to monitor equipment condition.
Definition of Preventive Maintenance, PM Elements, Plant Characteristics In Need of a PM Program, Principle for Selecting Items for PM, PM Measures, PM Models with examples
The document describes a case study applying reliability-centered maintenance (RCM) methodology to develop a maintenance plan for a steam-process plant in Egypt. The plant consists of a fire-tube boiler, feed-water pump, dryers, and process heater. A failure mode and effect analysis was conducted for critical equipment. The boiler and pump were found to be critical. An RCM-based maintenance program was developed that decreased labor costs by 25.8% and downtime costs by 80% compared to the plant's current maintenance.
The document discusses plans for implementing a preventive maintenance program at a residential life facility. It outlines preparations like gathering equipment data, labeling systems, and preparing equipment. It describes the maintenance management system that will be used to schedule tasks. Implementing preventive maintenance is expected to save significant time on tasks like filter changes. Challenges may include social and technical factors, but the benefits of preventive maintenance in reducing costs and downtime outweigh these challenges.
Maintenance and Operation Management-Emergency Management System YoungTae (Henry) Huh
This document provides an overview of maintenance and operation for an Emergency Management System (EMS) case study in Bangladesh. It describes the key components of an EMS including software, hardware, network architecture and users. It then covers various aspects of maintaining and operating the EMS such as defining maintenance and operations, the management process, necessary systems and tools, required organization and human resources, different phases and types of maintenance. It also discusses methods, procedures and checks for regular and special maintenance of the EMS.
Definition, types of corrective maintenance, steps and cycle;
Measures of corrective maintenance are: Mean Corrective Maintenance Time , Median Active Corrective Maintenance Time, Maximum Active Corrective Maintenance Time.
Then different models : a system that can either be in up (operating) or down (failed) state; a system that can either be operating normally or failed in two mutually exclusive failure modes; a system that can either be operating normally, operating in degradation mode, or failed completely; a two identical-unit redundant (parallel) system. At least one unit must operate normally for system success.
Preventive maintenance refers to regularly scheduled maintenance tasks that are intended to prevent equipment failures and unplanned downtime. It involves careful planning and scheduling of inspections and servicing before issues occur. Recommended standards help determine what maintenance is needed and how often based on the equipment type and operation. The benefits of preventive maintenance compared to reactive maintenance include cost savings of 12-18% from less downtime, repairs, and errors as well as prolonged equipment life.
The document discusses different types of maintenance activities. It defines maintenance and its objectives to keep equipment operational at minimum cost. It describes various types of maintenance including planned preventive maintenance to minimize breakdowns, and unplanned corrective maintenance after failures occur. Predictive maintenance uses condition monitoring to detect potential failures while preventive maintenance relies on routine inspections.
Simple Steps to Improve Your Maintenance ProgramTranscat
Presented by John Bernet of Fluke Corporation, Fluke and Transcat detail the benefits of a proactive maintenance program and how it compares to historical reactive, preventive, and predictive maintenance schedules.
The Future of Maintenance Management: 11 Trends Shaping Your Workplace and Ho...Jason Johnson
Join us as we explore eleven emerging trends in maintenance management and how, with the help of CMMS software, you can capture critical data for making good decisions to help your organization save time and money.
The document discusses maintenance management and provides definitions of key terms. It describes the evolution of maintenance from simply fixing equipment when it breaks to more modern approaches like reliability centered maintenance (RCM). The objectives of maintenance are to preserve asset functions and avoid failures. The functions of maintenance management include physical asset management, maintenance strategy determination, and planning and scheduling maintenance work. Different maintenance strategies like preventative maintenance and condition-based maintenance are also covered.
Reliability centered maintenance (RCM) integrates different maintenance strategies including reactive, preventive, predictive testing and inspection, and proactive maintenance. The goal of RCM is to maximize reliability and minimize maintenance costs and downtime. RCM involves analyzing systems to understand failures, prioritizing failures based on consequences, and determining the best strategy to address each failure. Common applications of RCM include the aviation, spacecraft, nuclear, and defense industries where minimizing downtime is critical.
It saves more then it costs....
Preventive maintenance and reactive maintenance are an extremely critical part of any fleet operations. By creating a Preventive Maintenance program to decrease the incidents of equipment arriving late for the PM’s they are due for, this program can be an integral part of cost savings and reduction of equipment downtime for repairs.
Hello Everyone!
This is the best ppt on 'Industrial Maintenance' that you can ever find. I tried to include all the topics related to the maintenance of industry. These notes will also be helpful from university exam point of view. Go through the whole ppt and leave a feedback in the comment box. Learn and Enjoy!
Thank You!
This document discusses how utilities are moving from traditional time-based maintenance to condition-based maintenance (CBM) by leveraging new technologies to optimize asset management. CBM utilizes data from inspections, testing, predictive maintenance technologies and online monitoring to determine the optimal maintenance strategy. The document outlines how utilities can better implement CBM by integrating their data management systems, which analyze condition monitoring data, with their work management systems, which plan and schedule maintenance work, to create a closed-loop process where data drives maintenance decisions and work orders. Automating data collection and integrating different data sources enables a more effective overall asset management strategy focused on CBM.
This document summarizes trends in maintenance management approaches over time. It discusses early approaches like breakdown maintenance from before 1950. It then outlines the development of preventive maintenance between 1950-1960, predictive maintenance between 1960-1970, condition-based maintenance, total productive maintenance between 1970-1985, and computerized maintenance management systems after 1985. The document provides examples of each approach and concludes that while new trends emerge, older approaches still have applicability depending on the situation.
How to set up a Preventive Maintenance ProgramSchoolDude
The document discusses the importance and best practices of implementing a preventive maintenance (PM) program. It outlines that PM programs can reduce emergency work orders by 25% and lower overall maintenance costs by performing cheaper scheduled maintenance. A successful PM program follows four steps: 1) determining PM schedules and plans, 2) assigning staff, 3) gaining management support, and 4) ongoing reporting and improvement. Regular maintenance can extend equipment lifespan, improve safety and energy efficiency, and lower long-term costs compared to deferred maintenance. The SchoolDude PMDirect software allows for automated PM work generation and performance tracking to help facilities teams successfully implement and monitor a PM program.
Este documento presenta una serie de ejercicios resueltos sobre análisis de circuitos eléctricos en serie, paralelo y mixtos. Inicia explicando la ley de Ohm y cómo calcular corriente, voltaje y resistencia en un circuito simple. Luego cubre temas como sumar resistencias en serie y paralelo, así como calcular voltaje y corriente total para circuitos con múltiples componentes. Finaliza con un ejemplo sobre un circuito mixto y los pasos para reducirlo a su resistencia equivalente.
Este documento describe cómo resolver un circuito eléctrico mixto con resistencias en serie y paralelo para encontrar las variables como voltaje, corriente y resistencia equivalente. Primero se calcula la resistencia equivalente de cada agrupación en paralelo, luego se trata el circuito completo como uno en serie. Finalmente, se analizan las corrientes y voltajes individuales en cada rama.
This document discusses implementing a condition-based maintenance (CBM) program across an entire enterprise using the OSIsoft PI System. It describes CBM as a proactive approach that monitors assets for early signs of degradation to predict and prevent failures. The document outlines how to collect asset data, structure it for analysis and visualization, and create a web portal to monitor asset conditions and receive notifications. Implementing this CBM methodology can help organizations optimize maintenance processes and reduce costs through more efficient asset management.
Los componentes eléctricos pueden conectarse en serie o en paralelo. En una conexión en serie, la misma corriente fluye a través de cada componente y la tensión total es la suma de las tensiones individuales. En una conexión en paralelo, la misma tensión se aplica a cada componente y la corriente total se distribuye entre ellos. Un cortocircuito hace que toda la corriente fluya a través de la ruta de menor resistencia, en lugar de a través de los componentes deseados.
Este documento presenta información sobre circuitos eléctricos de corriente directa. Explica conceptos como resistencias en serie y paralelo, y cómo calcular las resistencias y corrientes equivalentes en circuitos simples y complejos. El objetivo es que los estudiantes aprendan a determinar las resistencias y corrientes en cualquier circuito eléctrico usando las leyes de Kirchhoff y Ohm.
El documento explica la ley de Ohm para circuitos en serie. Indica que la corriente es la misma en todas las resistencias y que el voltaje total es igual a la suma de los voltajes individuales en cada resistencia. Además, muestra ejemplos numéricos para calcular el voltaje total, los voltajes individuales y la resistencia total equivalente de un circuito en serie dado la corriente y las resistencias individuales.
Maintainability analysis of an offshore gas compression train system: A case ...Irfan Ullah Khan
This document presents a case study on maintainability analysis of an offshore gas compression train system.
The study proposes a methodology to analyze maintenance downtime data over time to identify improvement trends and critical subsystems. Applying this to a gas compression train system, the analysis found improvement trends from enhanced spare parts logistics and equipment scheduling. It also identified gas turbines and logistic operations as subsystems requiring attention to reduce downtime.
The study compared different data modeling methods and found the lognormal distribution provided the best fit. This allowed more accurate calculation of key maintainability measures like mean downtime. The analysis provided insights for effective maintenance planning and future system design improvements to minimize downtime.
Design of an accuracy control system in ship building industryGopalakrishnan P
This document summarizes a study on implementing an Accuracy Control System (ACS) in an Indian shipyard to improve quality and reduce reworks. A pilot study was conducted on the plasma cutting machine. Data on dimensional variations was collected and control charts were developed. The analysis found the process to be out of control. Major causes of variation like fluctuations in power supply voltage and issues with input design data were identified through cause-and-effect analysis and testing. It was recommended to use advanced voltage regulators and calibrate the input design data to minimize variations and improve the plasma cutting accuracy. The ACS is expected to enhance quality and reduce production costs.
RGT is a planned test-analyze-and-fix (TAAF) process in which End Unit is tested under actual, simulated, or accelerated environments to disclose design deficiencies and defects. It is intended to provide a basis for early incorporation of corrective actions and for verification of their effectiveness, thus promoting reliability growth. RGT is intended to correct failures that reduce operational effectiveness and failures that increase maintenance and logistics support costs.
Statistical Process Control (SPC) is a method of using statistical analysis to monitor and control a process. SPC helps determine whether a process is stable or unpredictable by comparing data to control limits on charts. There are control charts for variables (data that can be measured numerically) and attributes (data classified into categories). The document discusses types of control charts like p charts for proportions and u charts for defects per unit. It also covers process capability indices, which measure how well a process produces outputs within specifications. The goal of SPC is to detect non-routine variations and make processes as consistent as possible through continuous improvement.
This document provides information about tools and templates for a RIBA quality management toolkit. It includes definitions and descriptions of common quality management tools such as check sheets, control charts, Pareto charts, scatter plots, Ishikawa diagrams, histograms, and others. Links are also provided to additional free resources on quality management topics like systems, courses, standards, and strategies.
Here's a copy of DENR semi annual report (CMR). This report is submitted in compliance of ECC condition. Said report is submitted on or before July 15 (1st half) and Jan 15 (2nd half) of every year
The document provides information about quality management strategy templates including templates, tools, and strategies. It then lists additional quality management resources and templates. The rest of the document outlines a quality management strategy template, including defining quality requirements and standards for both products and processes, quality assurance metrics and processes, and three common quality management tools - check sheets, control charts, and Pareto charts.
The graphical analysis for maintenace management methodPeterpanPan3
This article proposes a new graphical tool called the Graphical Analysis for Maintenance Management (GAMM) method to support maintenance management decision making. The GAMM method visualizes equipment dependability data like the number and duration of corrective and preventive interventions over time. It helps identify opportunities to improve operations and maintenance by analyzing patterns in the timing and impacts of interventions. The GAMM method estimates reliability using nonparametric estimators and graphs cumulative intervention rates over time based on historical maintenance data.
The document provides a comprehensive guide for developing transformer assessment indices. It discusses key steps such as determining the purpose of the index, identifying failure modes to include, and designing a scoring system. The guide outlines different types of indices for various purposes like replacement or repair. It also addresses handling missing data and calculating a quality score to indicate confidence in the assessment. The overall document aims to help asset managers develop indices that provide useful information for medium to long term asset planning decisions.
This document provides an overview of control charts, which are statistical process control tools used to monitor manufacturing processes. It discusses the key elements of control charts, including center lines, control limits, data collection sections and how points inside or outside the control limits indicate whether a process is in or out of statistical control. The document also describes different types of control charts for variables and attributes data and their functions in improving process performance over time. Specifically, it focuses on X-bar and R charts, which are used when measurements are collected in subgroups, and how statistical data is required to construct these charts, including determining the number of subgroups.
This document discusses quality management strategy and provides resources and tools for quality management. It begins by explaining that having a clear quality management strategy is important for PRINCE2 projects to ensure customer expectations are met. It then provides details on developing a quality management strategy, including defining quality expectations, standards, and management procedures. Finally, it introduces several quality management tools, including check sheets, control charts, Pareto charts, and scatter plots.
- Seven tools;
- Process variability;
- Important use of the control chart;
- Statistical basis of the control chart:
> Basic principles and type of control chart;
> Choice of control limits;
> Sampling size and sampling frequency;
> Average run length;
> Rational subgroups;
> Analysis of patterns on control charts;
> Sensitizing rules for control charts;
> Phase I and Phase II of control chart.
This document discusses joint optimization of statistical process control (SPC) and preventive maintenance. It describes different types of control charts that can be used for SPC, including X-bar charts. Preventive maintenance aims to avoid equipment failures by conducting maintenance activities regularly. The document presents a model to optimize SPC sampling intervals, sample size, control limits and preventive maintenance schedules to minimize total operational costs. The model utilizes information from quality control charts to inform maintenance decisions.
The document discusses statistical process control (SPC). It provides an overview of SPC, including its history and importance in quality control. It describes the basic steps of SPC and the types of variation that can occur in processes. Common SPC tools like control charts are explained, along with how they are constructed and interpreted. The document also provides examples of how SPC was implemented at Tata Consultancy Services to reduce defects and improve process performance.
The document discusses maintenance management. It defines maintenance as keeping equipment operational or repairing it. The objectives of maintenance are increased availability, safety, and optimized costs. Maintenance management involves managing maintenance functions. Common maintenance strategies discussed are breakdown, preventive, predictive, opportunity, and design-out maintenance. Functions of the maintenance department include maintaining equipment, installations, preventive maintenance, condition monitoring, modifications, inventory management, and record keeping. Elements of effective maintenance management discussed are maintenance policy, materials control, work orders, job planning, data recording, and performance measurement.
Measurement and Evaluation of Reliability, Availability and Maintainability o...IOSR Journals
The growing complexity of equipments and systems often lead to failures and as a consequence the
aspects of reliability, maintainability and availability have come into forefront. The failure of machineries and
equipments causes disruption in production resulting from a loss of availability of the system and also increases
the cost of maintenance. The present study deals with the determination of reliability and availability aspects of
one of the significant constituent in a Railway Diesel Locomotive Engine. In order to assess the availability
performance of these components, a broad set of studies has been carried out to gather accurate information at
the level of detail considered suitable to meet the availability analysis target. The Reliability analysis is
performed using the Weibull Distribution and the various data plots as well as failure rate information help in
achieving results that may be utilized in the near future by the Railway Locomotive Engines for reducing the
unexpected breakdowns and will enhance the reliability and availability of the Engine. In this work, ABC
analysis has been used for the maintenance of spare parts inventory. Here, Power pack assemblies, Engine
System are used to focus on the reliability, maintainability and availability aspects
Guidelines to Understanding to estimate MTBFijsrd.com
To quantifying a reparable system or reliability we can use MTBF. It has been used for various decisions. MTBF is determining the reliability. For developing the MTBF model we can use Poisson distribution, Weibull model and Bayesian are the most popular approach. In this paper we are talking about complexities and misconceptions of MTBF and clarify in sequence what are the items and concerns that need to be consider in estimating MTBF.
Control charts are statistical tools used to determine whether a manufacturing or business process is stable and predictable or experiencing unpredictable variation. Walter Shewhart invented control charts in the 1920s at Bell Labs to monitor telephony processes. Control charts plot process data over time along with an average line and upper and lower control limits set at 3 standard deviations from the average. As long as data points remain within the control limits, the process is considered in a state of statistical control and predictable. Points outside the limits suggest an unpredictable special cause of variation that requires investigation. Control charts allow detection of changes in a process's natural variation that may require adjusting process parameters.
Your One-Stop Shop for Python Success: Top 10 US Python Development Providersakankshawande
Simplify your search for a reliable Python development partner! This list presents the top 10 trusted US providers offering comprehensive Python development services, ensuring your project's success from conception to completion.
Building Production Ready Search Pipelines with Spark and MilvusZilliz
Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
leewayhertz.com-AI in predictive maintenance Use cases technologies benefits ...alexjohnson7307
Predictive maintenance is a proactive approach that anticipates equipment failures before they happen. At the forefront of this innovative strategy is Artificial Intelligence (AI), which brings unprecedented precision and efficiency. AI in predictive maintenance is transforming industries by reducing downtime, minimizing costs, and enhancing productivity.
zkStudyClub - LatticeFold: A Lattice-based Folding Scheme and its Application...Alex Pruden
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1. A control chart guided maintenance policy selection
Suprakash Guptaa
*, Jhareswar Maitib
, Ravi Kumarc
and Uday Kumard
a
Department of Mining Engineering, Institute of Technology, BHU, Varanasi, Uttar Pradesh,
India; b
Department of Industrial Engineering and Management, Indian Institute of Technology,
Kharagpur, West Bengal, India; c
Reliability Engineering Centre, Indian Institute of Technology,
Kharagpur, West Bengal, India; d
Division of Operation and Maintenance, Lulea˚ University of
Technology, Lulea˚, Sweden
(Received 29 July 2008; final version received 7 February 2009)
In addition to adopting new and advanced technology, effective maintenance
management is one of the key parameters for meeting ever increasing
production targets both in terms of quality and quantity. A lot of capital
may be drained off in the absence of sound maintenance policy and there is
ample scope to minimise this loss through proper maintenance decisions. This
study aims to develop a scheme for maintenance policy decisions through a
time-based control chart (t-chart) that monitors the failure process of the
component or system under investigation. On the basis of the nature of the
control chart, eight maintenance policy zones were identified. A case study on
an Armoured Flexible Conveyor (AFC) used in an underground coal mine in
India was undertaken to illustrate the use of the developed scheme for making
maintenance policy decisions.
Keywords: control chart; failure process monitoring; maintenance policy; Weibull
distribution
Introduction
Maintenance is an increasing portion of operating cost and requires to be
thorough planning to ensure that each maintenance dollar is well spent [1].
Therefore, organisations should have a maintenance policy to guide the
maintenance department in planning and scheduling of all maintenance activities.
A maintenance policy is a statement of principle, usually containing a set of rules,
used to guide maintenance management in decision-making for maintenance
planning. There are two aspects of maintenance planning, namely, identification
of correct maintenance actions from an analysis of past and recurrent failures,
and planning and scheduling of all maintenance actions directed to improve the
efficiency of the maintenance function [2]. Maintenance policy normally addresses
maintenance related queries like when to do maintenance, how to do maintenance
or whether the present schedule for maintenance is apt (i.e. cost effective/as per
with the failure process) or needs modification. A suitable failure process
*Corresponding author. Email: suprakash@bhu.ac.in
International Journal of Mining, Reclamation and Environment
Vol. 23, No. 3, September 2009, 216–226
ISSN 1748-0930 print/ISSN 1748-0949 online
Ó 2009 Taylor & Francis
DOI: 10.1080/17480930902916478
http://www.informaworld.com
2. monitoring scheme may be adopted that will serve as an effective tool to the
management in framing the maintenance policy.
A control chart is an useful tool for process monitoring in any industry. The
basic purpose of developing a control chart is to identify assignable causes of
deviations of process parameters. The principles behind developing a control chart
are (i) all processes behave in a typical manner based on their inherent
characteristics, which are termed as common cause variation and (ii) in the presence
of assignable causes, the process behaviour changes and the symptoms of these
changes are manifested by the process characteristics [3]. Each component has its
own characteristic life and it fails after this because of the common cause of ageing.
As the failure of the components of equipment is a random process and caused by
common causes, control chart principles can be applied for monitoring the failure
process of the components of equipment to detect the presence of assignable causes
and their removal. For example, the assignable causes may be sudden increase of
stress and human error, and common causes are the inherent characteristics of the
machine component.
Xie et al. [4] has adopted the control scheme proposed by Chan et al. [5] for
monitoring the reliability of a component or system. This approach can ease out
the problem of large data requirement in standard control charts like Shewart
control charts and can easily be adapted to failure process monitoring in
maintenance engineering. Cassady et al. [6] have used an "X chart with an age
related preventive maintenance policy for optimisation of the operating cost of
manufacturing equipment. In this article, the control chart principle developed by
Xie et al. [4] is applied to monitor the failure process of the components of an
Armoured Flexible Conveyor (AFC) being used for conveying coal from an
underground Longwall face. A framework for maintenance policy decisions is
developed based on the failure causes of the components of the AFC as depicted
in the control charts.
Development of control chart for monitoring of time between failure
The failures of a component can be described by a continuous statistical distribution
like the Weibull and lognormal distributions. However, the Weibull distribution has
one very important property in that the distribution has no specific characteristic
shape. In fact, depending upon the values of the parameters, it can be shaped to fit a
set of data that cannot be characterised as a particular distribution other than a
Weibull distribution with certain shaping parameters. The construction of control
charts for Weibull distribution based on Xie et al. [4] is given below.
The cumulative distribution function (CDF), F (t) of a two-parameter Weibull
distribution is,
FðtÞ ¼ 1 À exp
t
Z
b
; t 0 ð1Þ
where Z ¼ scale parameter and b ¼ shape parameter.
Xie et al. [4] termed their control chart t-chart to monitor the time between
failures (TBFs) of components. The t-chart is a function of the scale (Z) and
shape (b) parameters of the Weibull Distribution. Like standard control charts,
‘‘the control limits for t-chart are defined in such a manner that the components’
International Journal of Mining, Reclamation and Environment 217
3. failure process is considered to be out of control if the time to observe
exactly one failure is less than lower control limit (LCL), TL or greater than
upper control limit (UCL), TU’’. As the control limits are set based on the
properties of sampling distribution, there is always a chance of false alarm when
the failure process is characterised by the common causes with a very low
probability value and is termed as Type-I error (a). The acceptable level of Type-I
error (a) depends on the material of the component used, maintenance
effectiveness, human performance and environmental factors. For an acceptable
Type-I error (a), the control limits can be calculated from the following
expressions:
Central Limit; TC ¼ CL ¼ Z À 1 þ 1=bð Þ½ Š ln 2 ð2Þ
Lower control limit, TL ¼ LCL ¼ Z ln 1=1 À a=2ð Þ½ Š1=b
ð3Þ
Upper control limit, TU ¼ UCL ¼ Z ln 2=að Þ½ Š1=b
ð4Þ
Development of a framework for maintenance policy decisions
Monitoring of the component’s failure by t-chart shows its failure behaviour and
helps to take required maintenance actions following the maintenance policy as
given in Table 1. Components’ performance as well as the effectiveness of the
present maintenance schedule is said to be satisfactory when the TBFs points lie
in between the CL and UCL, and average and within control when the TBFs lie
around the CL and above the LCL provided that there are no systematic patterns
on the TBF values. The performance of the present maintenance schedule is
unsatisfactory and the component is deteriorating when the TBFs points are
around the LCL in the t-chart. When the TBFs data show any systematic pattern
it is also a cause of concern, as a pattern reflects the possible presence of
assignable causes. TBFs less than LCL mean that the failure occurrence rate has
increased resulting in a decrease in the failure time. On the other hand, if TBF
exceeds the UCL, this signals a possible process improvement. If this happens,
the management should look for possible causes for this improvement and the
follow-up actions should aim to maintain them. The policy or approach that had
helped this improvement should be maintained or even implemented for other
similar systems or equipment.
Application of control chart based maintenance policy – a case study
The developed control chart based maintenance policy was applied to an AFC
operated in a Longwall mine in India. The schematic for applying the methodology
is shown in Figure 1. The AFC is divided into manageable components and TBF
data for each of the components were collected. The failure data were analysed and
control charts for each of the components were developed. Finally, the components
were classified based on their control chart characteristics and an appropriate
maintenance policy for each class was outlined. The details of the application are
described in the following sections.
218 S. Gupta et al.
4. Table 1. Control chart characteristics and its meaning in maintenance policy.
Zone no Control chart characteristics Possible causes
Maintenance
policy
0 All points are within control limits
and no systematic pattern exists.
Common causes
of failures
Follow present
maintenance
policy.
I t-chart of TBFs show some points are
outside the upper control
limit (UCL) including points
on the limit line (UCL).
Signals a possible
process
improvement or
adoption of
better
maintenance
scheme or both.
For the first two
causes, maintain
the present
maintenance
policy. Follow
the same policy
for alike
components.
Component may
be under-loaded
due to misfit
that results in
delegating its
load over others
or over-design.
For the last cause,
redesign system.
II t-chart of TBFs show some
points are outside the lower
control limit (LCL) including
points on the limit line (LCL).
Signals possible
process
deterioration
and component
has reached in
wear out phase
(old) or in burn-
in phase (new).
Depending on the
age of the
component,
replace if it is
old or watch for
some more time
before framing
its maintenance
schedule when it
is new.
Presence of
extraneous
causes such as
roof fall in
underground
coal mines.
Some assignable
causes likely to
be present and
need to be
investigated.
III t-chart of TBFs show all points
within control limits but several
points’ line up consecutively
only between CL and UCL.
Signals possible
permanent
process
improvement,
e.g. adoption of
better
Follow the
changed
maintenance
policy.
(continued)
International Journal of Mining, Reclamation and Environment 219
5. Table 1. (Continued).
Zone no Control chart characteristics Possible causes
Maintenance
policy
maintenance
policy.
May increase the
periodic
inspection or
replacement
interval.
IV t-chart of TBFs show all points
within control limits but
several points’ line up
consecutively only between
CL and LCL.
Signals possible
permanent
process
deterioration,
e.g. adoption of
inadequate
maintenance
policy or
inferior quality
components/
spares.
Change the
present
maintenance
policy.
May decrease the
periodic
inspection or
replacement
interval.
Institute intensive
quality check.
V t-chart of TBFs show all points within
control limits but there is continuous
rise or fall in a series of points.
Component is
overstressed or
under-stressed,
possibly due to
change in
operating
conditions or
change in
maintenance
crew or spare
parts quality.
Investigate the
changes in
operating
conditions or in
maintenance.
Necessitates
modification in
present
maintenance
schedule in
coherence with
the changed
operating
conditions.
VI t-chart of TBFs show all points within
control limits and the points show
the same pattern of change over
equal intervals.
It’s a complex
phenomenon
and is very
difficult to
evaluate the
The only way is to
follow the
changes in TBF
closely, and
make a technical
(continued)
220 S. Gupta et al.
6. Mine description
A case study was undertaken in two longwall panels (Panel – A Panel – B) of an
underground coal mine in Southern India. The A panel is located between TG
35 LS and MG 40 LS and worked with a face length of 158 m. A total of 434,416
tonnes of coal was extracted in 12 months from this panel. The B panel is located
between TG 41 LS and MG 44 LS and worked with a face length of 136.5 m. A
total of 551,577 tonnes of coal was extracted in 8 months from this panel. Detailed
geology and layout of a coal face can be found in the article of Gupta et al. [7].
Failure data of the AFC used in these two longwall panels were collected through
field visits.
Data collection
Performance monitoring of components calls for sufficient information on the time
to failure characteristics of that unit under the specified conditions of use. Although
data from life tests serve as a good source of this information for Longwall mining
equipment like AFC, this sort of data is not available and normally collected from
the field. For the present study, various failure and maintenance information of the
AFC for a 2 year period was collected from the records kept in the mine, and the
Table 1. (Continued).
Zone no Control chart characteristics Possible causes
Maintenance
policy
causes. One of
the causes of
such behaviour
may be the
periodic
replacement of
another
component
which influences
the failure
characteristic of
the component
of interest.
decision
regarding
maintenance
and/or
operations.
VII t-chart of TBFs show all points within
control limits but the points stick
close to the CL or control limit
lines (UCL or LCL).
Indicating mixing
of failure data
obtained for
different
components or
similar
components
under different
operating
conditions.
Data recording
and
classification
system is
inadequate and
need to be
changed.
International Journal of Mining, Reclamation and Environment 221
7. concerned persons were consulted for grouping of the data. This period includes the
salvage period between these two panels. Necessary correction for the salvage period
was made to the TBF data for all the components.
Calculation of time between failures
TBFs for each component of AFC were calculated from the collected field data in
following steps and tabulated in Table 2.
Figure 1. A flow-chart for control chart based maintenance policy selection.
222 S. Gupta et al.
9. . Step 1: Note the dates and times of failures from the field record.
. Step 2: Find the number of working days between two successive failures of the
same component (dn). This calculation was done for the total study period, i.e.
from the starting of the first panel to the end of the second panel.
. Step 3: Calculate the equipment working hours (wh) between two successive
failures of the same component by multiplying the number of days (dn) with
16.5, the number of working hours per day. As the mine was operating in four
shifts of 6 h duration and the equipment remains idle in the pre-maintenance
shift. Average equipment operating hours per shift was 5.5 h as half an hour is
lost due to change of shifts.
. Step 4: Calculate the TBFs by subtracting the number of breakdown hours of
the equipment owing to failure of other components within the period of
interest from the equipment working hours (wh). Incorporate proper correction
for the exact time of failure, i.e. in which shift and at what time the failure was
reported on the particular dates.
Analysis of failure data
Once the TBFs for all the components of AFC were calculated, the next step is to fit
the data to a distribution by which they can be best described and subsequently, the
parameters of the fitted distribution are estimation. As the result of trend test suggests
that the data are identically distributed and absence of correlation advocates their
Table 3. List of scale parameter, shape parameter and control limits for the components of
AFC.
Component
no (Ci) Component name
Scale
parameter
(Z)
Shape
parameter
(b) CL UCL LCL
1 Adjusting pan 473.792 0.969862 332.6192 3320 0.5213
2 Attachment bracket 793.152 0.968203 556.8324 5576 0.8625
3 Bolts 1611.63 2.11333 989.1189 3938 70.715
4 Bursting disc 1074 1.40235 669.1386 1871 154.047
5 Chain connector 1311.07 1.04757 890.2909 7951 2.3908
6 Chain links 111.852 1.12578 74.28683 599 0.3161
7 Deck plate 581.54 1.83264 358.2186 1629 15.80
8 Drive shaft 666.497 1.1628 438.1832 3381 2.2707
9 Flight bars 108.879 1.0879 72.82737 618 0.2508
10 Fluid coupling (MG) 582.867 0.791018 460.2906 6343 0.1374
11 Fluid coupling (TG) 479.744 0.79393 378.8492 5175 0.1166
12 Fusible plug 1083.6 0.858649 809.9091 9770 0.4933
13 Gear box 164.128 2.07487 150.7456 408 6.7962
14 Inspection door 615.324 0.810079 477.6849 6330 0.1766
15 Oil seal (MG) 555.376 3.2836 345.4141 987 74.257
16 Oil seal (TG) 707.044 1.2276 457.678 3292 3.2513
17 Pan connector 678.771 0.709884 584.296 9703 0.0616
18 Ramp pan 153.396 0.581485 166.8578 3945 0.0018
19 Spill plate 484.085 0.856476 363.7308 4389 0.2161
20 Spill pan 1244.78 0.962259 877.7954 8857 1.2977
21 Sprocket assembly 1117.23 1.68444 690.9487 3428 22.114
22 Sprocket bearings 591.227 1.45999 370.7966 2155 6.4035
23 Triangular socket 334.65 0.811455 259.7918 3429 0.0974
224 S. Gupta et al.
10. independency, a classical distribution may therefore fit to the data [8]. Studies by
Ramani et al. [9] and Gupta et al. [10] show that the failure behaviour of longwall
equipment can be best described by a two-parameter Weibull distribution. Mann’s
test was done for goodness-of-fit tests of the TBF data to two-parameter Weibull
distribution. Test results are in favour of accepting the null hypothesis H0:- TBF of
AFC components are Weibull. Parameters of the two-parameter Weibull distribution
for the components of the AFC were estimated using STASTICA (version 5) as given
in Table 3.
Results and discussions
Table 3 presents the control limit values for the components of AFC. The TBF
control charts show the pattern of the failure process of the components. TBF points
in conjunction with the control lines show deterioration or improvement of
components’ failure process. The patterns observed in TBF monitoring are
attributed to maintenance effectiveness or ineffectiveness of the case study
component. t-charts for all the components of AFC were prepared as shown in
Figure 2 for chain links. On the basis of possible control chart characteristics of the
components, they were classified into eight maintenance zones. The t-chart of chain
Table 4. AFC components with their zone of maintenance.
Zone of maintenance Component no (Ci)
Total number
of components Percentage
0 7, 12, 13, 21 4 17.39
I 4 1 4.35
II 6, 8, 9, 10, 14, 17, 18, 19, 23 9 39.13
III 15 1 4.35
IV Nil 0 0.00
V 1, 3, 11, 16, 20, 22 6 26.09
VI Nil 0 0.00
VII 2, 5 2 8.70
Figure 2. T-chart for chain links.
International Journal of Mining, Reclamation and Environment 225
11. links depicts a number of points below or on the LCL, clearly indicating its berth in
the maintenance zone II. Mostly failures of the chain links were caused because of
ageing as it was old, and sometimes due to the impact of falling rock or coal. The
number of components along with their zones of maintenance is shown is Table 4. Of
the 23 components of the AFC studied, 39.13% components fall under zone II
followed by zones 0 (17.39%) and V (17.39%). Maintenance policy for each of zone
of maintenance is given in Table 1. For example for the components falling under
zone II, the maintenance policies are:
. Depending on the age of the component, replace if it has reached its wear out
phase (old) or watch for some more time before fixing up its maintenance
schedule when it is new.
. Investigate whether there is any assignable cause leading to significant process
deterioration and eliminate the cause.
Conclusions
The general conclusion of this study is that control chart (t-chart) is a very simple
and effective tool for monitoring the failure process of a component. It is helpful to
judge the maintenance effectiveness i.e. whether the present maintenance is in
coherence with the failure process or required any change. It can be used as an
effective tool for maintenance management in making maintenance decisions. This
study shows that the overall status of maintenance in the AFC is not up to the mark.
The management should pay proper attention to this ever neglected but very
important aspect.
Acknowledgements
The authors thank the anonymous reviewers for their constructive comments and suggestions
on an earlier version of the article.
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