The Good Maintenance Guide 1. Introduction
1. Maintenance Management 1.1 Definitions (1) The Good Maintenance Guide 1. Maintenance Management 1.1 Definitions (1) Asset Any item of physical equipment
1. Maintenance Management 1.2. Definitions (2) The Good Maintenance Guide 1. Maintenance Management 1.2. Definitions (2) Asset function - What users expect from their assets (output, speed, safety, environmental integrity, quality ..) - The level of performance which the users require when the asset does its function
1. Maintenance Management 1.1. Definitions (3) The Good Maintenance Guide 1. Maintenance Management 1.1. Definitions (3) Asset failure Situation where the asset is no longer capable of fulfilling one or more of its intended functions
1. Maintenance Management 1.1. Definitions (4) The Good Maintenance Guide 1. Maintenance Management 1.1. Definitions (4) Maintenance Any activity carried out on an asset in order to - ensure that the asset continues to perform its intended functions - repair the asset
1. Maintenance Management 1.1. Definitions (5) The Good Maintenance Guide 1. Maintenance Management 1.1. Definitions (5) Maintenance management The coordination, control, planning, execution and monitoring of the right equipment maintenance activities of manufacturing operations
1. Maintenance Management 2. Objectives Preserve asset functions Avoid the consequences of failure of the asset safety failures: endanger personnel and equipment operational failures: result in product loss and cost of repair non-operational failures: result in cost of repair
1. Maintenance Management 3. Evolution (1) Definitions Availability time available for production - downtime time available for production = a measure of the equipment uptime Reliability the probability that equipment will not fail in a given time period = a measure of the frequency of downtime
1. Maintenance Management 1.3. Evolution (2) The Good Maintenance Guide 1. Maintenance Management 1.3. Evolution (2) Expectations of the maintenance function 1930 - 1950 1950 - 1980 1980 - 2000 Higher availability Lower costs Longer asset life Higher reliability Better product quality Safety integrity Environment integrity Show results Fix it when it breaks Higher availability Lower costs Longer asset life
1. Maintenance Management 1.3. Evolution (3) The Good Maintenance Guide 1. Maintenance Management 1.3. Evolution (3) Maintenance techniques 1930 - 1950 1950 - 1980 1980 - 2000 Condition monitoring Failure modes and effects analysis Computerized Maint. Management Systems RCM - TPM (see later) Fix it when it breaks Scheduled maintenance Planning systems Computerization
The Good Maintenance Guide 2. Maintenance Management Functions
2. Maintenance Management Functions 2.1. Overview Physical asset management identification of assets recording of information Maintenance strategy conducting the right maintenance Maintenance planning & scheduling work order management Resources management people, spare parts, tools Performance measurement
The Good Maintenance Guide 2. Maintenance Management Functions Physical assets management
2. Maintenance Management Functions 2.2. Physical Assets Management Maintenance is concerned with Assets Preservation of asset functions Renovation of assets Life extension of assets Replacement of assets
Maintenance Management Functions 2.2. Physical Assets Management Assets must be identified use an asset hierarchy to identify your assets example plant area (packing area) equipment (belt conveyor) item (gear box) part (bearing) standardize the equipment descriptions
Maintenance Management Functions 2.2. Physical Assets Management Asset information must be recorded record all equipment maintenance activities assign all maintenance costs establish and effectively use a documented history for each equipment
The Good Maintenance Guide 2. Maintenance Management Functions Maintenance strategy determination
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination Strategy Maintenance type Fix it when it fails Emergency maintenance Corrective maintenance Preventive maintenance Time based (calendar time or running time) Condition based Predictive maintenance Equipment redesign Modification maintenance Failure finding Routine maintenance
Reliability Centered Maintenance (RCM) Maintenance Management Functions 2.3. Maintenance strategy determination How can we assure that the maintenance conducted is the right maintenance and that it produces the required equipment reliability? Reliability Centered Maintenance (RCM)
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination RCM is a technique for reviewing equipment failures and for determining the right maintenance tasks RCM definition
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination RCM properties RCM ensures that all performed maintenance is cost effective RCM contradicts the traditional precepts that the reliability of equipment is directly related to operating age RCM focuses on preserving the functions of equipment, not on preserving the equipment itself
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination RCM steps Select the most critical equipment Determine the functions of the equipment Establish performance standards Determine type of failures Identify causes of failures Define effects of failures Categorize the effects of failures Identify appropriate maintenance tasks Establish an overall maintenance plan
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination RCM implementation Operations identifies the functions and performance standards Maintenance identifies the types of failures defines the most appropriate condition monitoring techniques builds a program Maintenance and operations collaborate on the consequences of identified failures carry out the program
Some important notes about failures Maintenance Management Functions 2.3. Maintenance strategy determination Some important notes about failures A part of equipment has suffered a failure when it is no longer capable of fulfilling one or more of its intended functions A failure mode or cause is any event which causes a failure A failure pattern is the relationship between the probability of failure of an item, and its age There are six distinct failure patterns, one of which is the bathtub curve
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination Bathtub curve Probability of failure Manufacturing & installation defects Useful Life Period Wear-out Period Operating time
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination Failure patterns A (bathtub curve) - starting with manufacturing and installation defects, going to constant failure probability, ending in a wear-out zone - example: new machines
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination Failure patterns B - constant failure probability, ending in a wear-out zone - example: abrasion
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination Failure patterns C - slowly increasing probability of failure - no identifiable wear-out age - example: fatigue
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination Failure patterns D - low failure probability when the item is new - rapid increase to a constant level
The Good Maintenance Guide Maintenance Management Functions 2.3. Maintenance strategy determination Failure patterns E - constant failure probability at all ages - example: rolling element bearings
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination Failure patterns F - starts with high failure probability - drops to a constant level
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination The most appropriate equipment maintenance strategy can be determined by The failure pattern that applies to a given failure mode Mean Time between Failures (MTBF): the number of failures in a given time period, divided by the time that the equipment was operating in that period FMEA (Failure Mode and Effects Analysis): identify all the events which are reasonably likely to cause each failed state
Maintenance types: emergency maintenance Maintenance Management Functions 2.3. Maintenance strategy determination Definition: maintenance work requiring immediate response from maintenance employees Goal: solve downtime, safety risk, danger or damage Properties: unplanned creates peaks and valleys in the work load expensive requires emergency spare parts purchasing Maintenance types: emergency maintenance
Maintenance types: corrective maintenance Maintenance Management Functions 2.3. Maintenance strategy determination Definition: restoring an asset to a preserved condition Goal: improve quality or performance Properties: planned a work order has been created the work is prepared Maintenance types: corrective maintenance
Maintenance types: preventive maintenance Maintenance Management Functions 2.3. Maintenance strategy determination Definition: replacements or overhauls scheduled on elapse of calendar time or elapse of running time Goal: reduce downtime and breakdowns extend the life of the equipment or system Properties: planned & prepared correct failure probability must be known original reliability must be restored Maintenance types: preventive maintenance
Maintenance types: routine maintenance Maintenance Management Functions 2.3. Maintenance strategy determination Definition: short periodic work carried out pre-dominantly on-line ex: inspections, lubrication, adjustments Goal: reduce downtime and breakdowns extend the life of the equipment or system Properties: planned & prepared Maintenance types: routine maintenance
Maintenance types: predictive maintenance Maintenance Management Functions 2.3. Maintenance strategy determination Maintenance types: predictive maintenance Definition: comparing the trend of measured physical parameters against known engineering limits Goal: detecting potential and hidden failures (see next slide) Properties: planned condition based
Maintenance types: predictive maintenance Maintenance Management Functions 2.3. Maintenance strategy determination Maintenance types: predictive maintenance Types of failures functional failure: the inability to meet the specified performance standard potential failure: a physical condition which indicates that the failure process has started (metal particles in oil) hidden failure: failure is not apparent until the function is attempted
Maintenance Management Functions 2. 3 Maintenance Management Functions 2.3. Maintenance strategy determination Maintenance types: predictive maintenance The majority of failures do not occur instantaneously but develop over a period of time (P-F Curve) . . 100% Failure can be detected Failure starts to occur Operating Condition P . Failure has occurred F Time - Possible actions at P - prevent functional failure - avoid consequences of the failure
Maintenance types: predictive maintenance 2. Maintenance Management Functions 2.3. Maintenance strategy determination Maintenance types: predictive maintenance Diagnostic devices: Vibration analysis Lubrication analysis Infrared thermography Ultrasonic testing Shock pulse methods Oil analysis Coolant analysis Wear particle analysis
The Good Maintenance Guide 2. Maintenance Management Functions Maintenance planning and scheduling
2. Maintenance Management Functions 2. 4 2. Maintenance Management Functions 2.4. Maintenance planning and scheduling Definitions Work request formal request to have work done. Can be filled out by a production or maintenance employee Work order Written authorization to proceed with a repair or other activity to preserve an asset function
2. Maintenance Management Functions 2. 4 2. Maintenance Management Functions 2.4. Maintenance planning and scheduling Work planning assigning work orders to a time period plan resources Work scheduling arranging the sequence of the work orders considerations priority availability of craftsperson availability of material and equipment desires of the operating personnel
2. Maintenance Management Functions 2. 4 2. Maintenance Management Functions 2.4. Maintenance planning and scheduling Work identification by operation or maintenance personnel Work order creation work order number date originator asset identification short description priority approved by Workflow
2. Maintenance Management Functions 2. 4 2. Maintenance Management Functions 2.4. Maintenance planning and scheduling Work preparation accounting code job description (sequence of events) crafts required material required tools required safety and environment considerations estimated hours
2. Maintenance Management Functions 2. 4 2. Maintenance Management Functions 2.4. Maintenance planning and scheduling Work execution Progress tracking Work analysis Recording information nature of occurrence of the failure nature of the failure nature of the repair total downtime, labor-hours and spare parts
2. Maintenance Management Functions 2. 4 2. Maintenance Management Functions 2.4. Maintenance planning and scheduling Work preparation Work preparations are important facilitate estimation assure that the job will be done in the most efficient manner contribute to training by indicating the methodology of the job the preparation can be used the next time the job has to be executed
2. Maintenance Management Functions 2. 4 2. Maintenance Management Functions 2.4. Maintenance planning and scheduling Priority system A priority system is established to ensure that the most needed work orders are scheduled first Example of priorities 0: emergency or safety work 1: work to start within 24 hours 2: work to start within 1 week 3: work to start within 1 month 4: turnaround or overhaul
2. Maintenance Management Functions 2. 4 2. Maintenance Management Functions 2.4. Maintenance planning and scheduling Backlog management What is Backlog: all work available to be done. Backlog work has been approved and prepared The backlog must be used as a tool to make decisions informs management about future needs for maintenance (contracting, more or less personnel) must be effectively managed so that it does not grow to an unmanageable size
The Good Maintenance Guide 2. Maintenance Management Functions Resource management
2. Maintenance Management Functions 2.5. Resource management Resources people spare parts tools Resource management matching the resources to the workload
2. Maintenance Management Functions 2.5. Resource management People Utilization of people can be improved by managing the size of the backlog contracting shift from unplanned to planned work smoothing the workload
2. Maintenance Management Functions 2.5. Resource management Spare Parts The optimal balance between the cost of holding and the cost of stockout must be achieved Classification of spare parts Function Usage rate fast moving slow moving
2. Maintenance Management Functions 2.5. Resource management Spare parts management the right parts in the right place at the right time in the right quantity create an equipment history analysis identify dormant or excess stock items establishment of workable stock levels, controlled by supply lead-time and usage
2. Maintenance Management Functions 2.5. Resource management Tools Tools are not consumable Tools must be: monitored maintained replaced on time
The Good Maintenance Guide 2. Maintenance Management Functions Performance measurement
2. Maintenance Management Functions 2.6. Performance measurement You can’t manage what you don’t measure Maintenance is often organized and performed without proper measures to determine its impact on the business’s success You need consistent and reliable data high quality analysis clear presentation of the information
2. Maintenance Management Functions 2.6. Performance measurements General Actual budget versus forecast Maintenance costs overhead, labor, contractors, spare parts as a % of sales per unit produced Safety and environmental performance
2. Maintenance Management Functions 2.6. Performance measurements Organization Ratio of contractors to company employees Ratio of production to maintenance employees Maintenance employees per supervisor Maintenance employees per planner % overtime hours % absenteeism
2. Maintenance Management Functions 2.6. Performance measurements Spare parts Inventory turnover Inventory accuracy level Inventory service level % downtime due to stockouts Materials versus labor ratio Dormant stock items Excess stock items
2. Maintenance Management Functions 2.6. Performance measurements Work order management Work order lead time Workload (backlog) level by craft by priority by type Man hours per work order Daily schedule completion % emergency, corrective, preventive and predictive maintenance of total activity
2. Maintenance Management Functions 2.6. Performance measurements Equipment Overall Equipment Effectiveness Reliability Availability Maintainability Mean time between Failure Costs for each asset center Return on investment
The Good Maintenance Guide 3. CMMS
3. CMMS 3.1. Definition CMMS = Computerized Maintenance Management System (computer replaces manual systems)
3. CMMS 3.2. Basic modules Asset register Work order management documentation equipment data management multi-level hierarchical filing system Work order management History file required for feedback maintenance of work preparations reporting Spare parts inventory control
3. CMMS 3.3. Optional modules Budget analysis Invoice / ordering control Condition Based Maintenance Manager Failure analysis
3. CMMS 3.4. Trends Internet-enabled bringing information and training to the shop floor transferring analysis data to equipment suppliers online equipment monitoring purchasing of spare parts (e-procurement) software vendors will host CMMS on their own servers (Application Service Providers)
3. CMMS 3.4. Trends (2) Data Input: Use of handheld computers by technicians Interfacing with bar code terminals Integration of Supply Chain Software and CMMS
4. Total Productive Maintenance TPM is a company-wide team-based effort to build quality into equipment and to improve overall equipment effectiveness (OEE) TPM principles, components, implementation and benefits are handled in detail in our Good Maintenance Guide
5. RCM versus TPM RCM is strong in determining what maintenance to do, while TPM is all about improving rather than merely maintaining your processes
The Good Maintenance Guide 6. Good Maintenance Management
6. Good maintenance management Principles Maintenance is recognized by management as an integrated, essential part of production Continuous improvement programs are in place performance is evaluated reasons for downtime are analyzed corrective actions are taken progress is measured
6. Good maintenance management There is a commitment to improve the ratio of planned versus unplanned work There is an emphasis on training Operators are involved in the maintenance of their equipment
6. Good maintenance management Benefits Equipment downtime reduction smoother running reduced waste higher return on investment increased equipment life repair history available People more efficient operation balance of workloads reduced overtime increased cooperation between production and maintenance departments Spare parts lower inventory levels lower usage
The end