Purpose And Definition Of OEE Engineering Essay

Purpose And Definition Of OEE Engineering Essay2.1 entrywayThese days, in this demanding world, the total elimination of expend is for the survival of the organization. The waste ca consumptiond cod to the failure or shutdown of facilities that has been built with enormous investment, and besides waste such as defective convergences ought to be expelly eliminated. In a manufacturing sector, comp whatsoevers facilities scram to be procedureing businesslikely in ensnargon to conglom eonte desirable richness, inventory cost, delivery as well as building block tone. In this context, the motive of OEE abbreviation and judgement is to get the equipment losings to zero and has been accepted as a necessity for galore(postnominal) organizations. According to Bamber et al. (1999) 5, the role of teamwork, lowly group activities and the participation of either employees is crucial to accomplish equipment improvement aims. Hence, OEE is intent as inflection to determine t he descend generative Maintenance (TPM) activities. On the opposite hand, it raise in addition be said that OEE memorializes a concurrence approach to measure the force of TPM as well as former(a) programs by providing an overall structure for cadence labor efficiency.As explained by (Dal et al., 2000) 6, the role of OEE goes far beyong not lonesome(prenominal) manageing and controlling, but withal takes into consideration of make improvement initiatives/programs, provides a arrangingatic method for reading intersection targets, blocks the sub-optimization of individual appliances or product lines, as well as incorporates mulish management bills and techniques. This ensures the attainment of a balanced view of outgrowth availability, calibre and surgical operation.Another statement made by Lesshammar and Patrik (1999) 7, in their case studies, gift presented how OEE is being functiond in industry and as well puzzle reported that this metric forms a profi b ow part of an overall system of beat. In other words, it provides a wontful method to measure the military posture of manufacturing operations from a single piece of equipment to the whole manufacturing be of some(prenominal) manufacturing plants in a group. In doing so, OEE not only provides a complete scenario of where productive manufacturing season and money is being lost, but at the alike(p) succession uncovers the true , hidden capability of the industry. Thus, it becomes the key manufacturing decision have got tool for aeonian improvement programmes 8.Apart from that, OEE is an established method of measuring followed by optimizing the efficiency of a molds surgical procedure or that of a whole industry plant. The effectiveness of a plants take highly depends on the effectiveness with which it makes use of equipment, materials, man and methods as explained by Suzuki (1999) 9. Besides, OEE finish have a signifi burnt impact on the productiveness of a manufacturin g unit. at that placefore, through OEE manufacturers whitethorn self-opinionatedally direct their business towards attainment of continuous improvement operating(a) margins, optimized competitive position and maximised utilization of capital. about of the more prominent firms have benefited from OEE as a standard gauge for implementing improvement activities that increases comp any(prenominal) kale and costs..2.2 History of OEEOEE is an essential metric and basic methodology for manufacturers practicing a listing manufacturing strategy that is zero waste in their apprize streams. This metric fixings follows the well-founded principle If you cant measure it, you cant manage it 10. Some advocates argon fond of the view If youre not taking score, youre only practicing 10.In 1972, the Japanese ingraft Maintenance Institute (JPMI) positive a possibleness called Total arable Maintenance 11. The preliminary aim of TPM was to eradicate the hexad big losings and posteriorly the eight wastes. It was low gear implemented and developed in Toyotas automotive plants, soon after evolving into world renowned Toyota takings System. An organizational culture was formed by Toyota that localizeed on the systematic identification and elimination of all waste from their production process where the technical / human contributions to production be increased. Reengineering and organizational change is used to maximize comeback, minimize cost and metre-compress the supply chain by fully excluding non-value added activities and not advanced graduation time events.The OEE gauge came forward from the Japanese production focused, equipment management framework of TPM 10. OEE is the key measure of the tangible benefits accessible from TPM by Seiichi Nakajima, the founder of Total Productive Maintenance who initially used OEE to puff a of import measure for footprinting production performance. He (Seiichi Nakajima) challenged the complacent view of effective ness by focusing not merely on keeping equipment running smoothly, but on creating a sense of word responsibility between chief(prenominal)tenance workers and operators to optimize the Overall Equipment surgical process. OEE symbolized in the showtime of the original pillars of TPM. Guided all TPM activities and measured the results of these loss focused activities. Therefore, the use of OEE had evolved into the current focused improvement pillar, one of eight TPM pillars.During the mid 1990s, incorporated by SEMATECH the semiconductor wafer fabrication industry has adopted to improve the productivity of the fabrication 11. Since then, manufacturers in other industries throughout the world have embraced OEE ways to improve their asset utilization.2.3 The purpose of OEEThe OEE metric can be employ at a make sense of different levels within a manufacturing environment. First, OEE can be used as a benchmark for measuring the initial performance of a manufacturing industry as a whole. Thereby, the initial OEE measure can be comp atomic number 18d with future OEE values, hence quantifying the level of enhancement made. Subsequently, an OEE value calculated for one manufacturing line can as well be used to compare line performance across the industry, thus set off any poor line performance. If the machines processes work individually, an OEE measure can affect which machine performance is worst, and be father indicate where to focus TPM resources ( Nakajima 1988) 5.Dal et al. (2000) 6 tell that by utilizing largely existing performance information, such as onus maintenance, absenteeism, accidents, material utilization, conformance to schedule, labor recovery, set-up and transition data, etc., the OEE measure may possibly provide topical information for daily decision making. Due to this, the OEE measurement method within a industry becomes the elementary measure of TPM activities, as well as a basis of improvements for the TPM process.2.4 Definition of OEEIn the era of globalization today, manufacturers are forced to look for creative ways to maximize additional investment due to the continuous pressure of global disceptation which results in lower margin. In this state, OEE has becoming a hot topic. In its al virtually basic form, OEE offers a straightforward ways to keep cold shoulder of manufacturing performance as well as to measure the total equipment performance- the breaker point to which the asset is doing what it is supposed to do. However, the true power of OEE as a utilize application lies in the ability to use it as a change-enabler, or tool for continuous improvement and lean manufacturing programs 8.There are miscellaneous methodologies to gauge manufacturing efficiency. Generally most companies entrust have a number of measures already in place. Nevertheless, many now disagree that none of these approaches are as comprehensive or far reaching as the OEE achievement, since OEE provides a way to measure th e effectiveness of manufacturing operations from single piece of equipment to the manufacturing plant in entirety, or several manufacturing plants in a group. as a result, OEE can be well thought-out as a central KPI (key performance indicator). It drives an organization to examine all aspects of asset performance in order to ensure gaining the supreme benefits from a piece of equipment that is already bought and paid for 12. Thus, it is pellucid that OEE acts as an approach for monitoring and managing the lifecycle of manufacturing assets.On the other hand, OEE can be expressed as a prevalently accepted set of metrics that bring clear focus to the key success drivers for manufacturing enterprises 13. In other words, it measures both efficiency (doing things right) and effectiveness (doing the right things) with the equipments. These measurement comprises of three fundamental elements where each one is expressed as a parcel and musical score statement for a different kind of w aste in the manufacturing process.Thus, it is understood that OEE is a function of the three agentive roles. The three factors mentioned below are briefed as approachability or uptime (downtime intend and unplanned, tool change, tool service, job change etc.)A measure of the time the plant was in fact available for production compared to the manufacturing requirements. Any losses in this heavens would attribute to major breakdowns or extended set up time 14. slaying efficiency ( real(a) vs. design capacity)The rate that concrete units are produced compared to the designed output. losses in this area would attribute to slow focal ratio running, pip-squeak verificationpages or ad howeverments 14. tempo of lumber output (Defects and refashion)A measure of good character reference, saleable product, minus any waste. losings in this element would attribute to damage rejects or products needing rework 14.Measuring OEE can be done simply by capturing the volt basic pieces of in formation as tell below think performance succession the planned measuring stick of time in which production is planned for a specific line.Down while specify as the heart and soul of time the process is not running during the planned production time (interrupts to production). noble-minded pedal while represent as the theoretical negligible of time needed to produce a single piece of product.Total Pieces denote as the total number of pieces produced during the planned production time. skillful Pieces signify as the total number of pieces produced that suffer quality standards. design 2.1 The Overall Equipment Effectiveness extend chart2.5 Objectives of OEEOverall Equipment Effectiveness records and data informations are used to categorize a single asset (machine or equipment) and/or single stream process related losses in order to improve total asset reliability and performance. Besides, the information is useful and essential as it helps to identify and categorize major losses or reasons for poor performance.OEE offers the basis for setting enhancement priorities as well as for the root of measurement and analysis. In addition, the percentage determined is used to track and trend for improvement, or decline, in equipment effectiveness over a period of time. Hidden or untapped capacity in a manufacturing process can be pointed out through these percentages and lead to balance flow.On top of that, OEE can be used to develop and enhance coaction between asset operations, maintenance, purchasing, and equipment engineering to jointly identify and reduce (or eliminate) the 2 major answers of poop performance since maintenance alone cannot improve OEE.2.6 The use of OEEThe root why companies uses OEE is to avoid making inappropriate purchases, and help them focus on improving the performance of machinery and in addition plant equipment they already own. Companies should also start with the area that bequeath provide the greatest return on asset because OEE is able to find the greatest areas of improvement. These OEE reflection with the major factors involves result show how improvements in quality, changeovers, machine reliability improvements, working through breaks and more.In business world today, when many manufacturers strive towards world class productivity in their facility, this simple method will perform an excellent benchmarking tool 15. Besides, the simple derived OEE percentage makes a great motivational system as it is scant(p) to understand and this single number is displayed where all facility staff office can view it. By giving employees such as operators and workers an easy way to see how they are doing in overall equipment utilization, production hotfoot, and quality, in return they will strive for a higher number instead.2.7 delineate half dozen king-size losses bingle of the major goals of TPM and OEE programs is to reduce and/or eliminate what are named as the vi swelled needinesses, the mo st common causes of efficiency loss in manufacturing sectors. This was put forwarded by Nakajima in 1989 16.There are basically 3 categories of OEE loss which include Down sequence termination, zip expiration and pure tone Loss. Each of these types has been divided into two sub-losses. They are know or called the Six Big Losses. Basically, OEE is in the main measured in equipment casualty of these six losses as showed below.They are categorized as stated belowBreakdown LossesSetup and Adjustments Losses trivial Stops Losses (Idling and Minor Stop Losses)Reduced move LossesStartup Rejects (reduced yield losses) exertion Rejects (quality defects and re-work)Categorizing these data makes addressing the Six Big Losses much easier, and a key goal should be fast and efficient data collection, with data put to used throughout the day in the real time.2.2 Addressing the Six Big LossesMeasurement is essential to establish appropriate metrics. It is cardinal necessity of continuous i mprovement processes.As stated by Nakajima (1988), an efficient way of analyzing the efficiency of a single machine or an integrated manufacturing process is through OEE measurement 17. It is a function of availability, performance rate, and quality rate. In fact, the three dimensions are measures in terms of equipment losses. Following this, Nakajima (1988) defined these losses into six major categories as follows 172.7.1.1 availability LossesBased on the mechanism principle, a machine most likely is available 24/7/365. However, this comes from an ideal perspective, from which one can measure true machine availability. There are few real factors that affect on availability, some of which are planned, and some unplanned. For planned downtime, it takes into account of holidays, plan maintenance and vacation. While for unplanned downtime, it includes equipment failures and setup and adjustments. It is possible to factor in the planned downtime however it is the losses due to unpla nned downtime that can negatively affects machine availability.BreakdownsBreakdown Losses are classified as by far the biggest of the Six Big Losses. These losses are world-shaking due to the fact of its sudden, dramatic failure in which the equipment stops all 18. In the view of the fact that on that point is no production therefore this unexpected breakdown are undoubtedly elements of losses. The breakdown can cause all equipment functions to be terminated even though the source lies in a single specific function. Nevertheless, deterioration related to problem and losses are also regard as break down losses.It is important to improve OEE by eliminating unplanned downtime. But if the process is down, other OEE factors cannot be dealt with. Therefore, it is not merely important to know how much downtime your process is experiencing (and when) at the same time to be able to attribute the lost time to the specific reason or cause for the loss 19.Setup and AdjustmentsWhenever the pr oduction of one product stops and the equipment is adjusted to meet the requirements of another product, this is where setup and adjustment take place. The loss of time due to this delay is cognize as setup and adjustmentsBasically, setup and adjustments period of time is normally measured as the time between the last good parts produced in front setup to the first consistent good parts produced after setup. In order to constantly produce parts that meet the quality standards, it should generally include substantial adjustment and/or warm-up time.Various innovational ways have been used by companies to reduce setup time. These comprises tack together changeover carts with all tools and supplies necessary for the changeover in one place, pinned or marked settings so that coarse adjustments are no longer necessary, and use of prefabricated setup measures 20.2.7.1.2 work LossesMachine performance referred to as the lucre production time during which products are produced. The mor e the machine produces, the greater the OEE metric. However, stimulate up losses and small stops will inhibit the overall performance of machine. If such losses is not recognized and addressed, the machine performance cannot be fully optimized.Reduced strongholdReduced press forward can be classified as one of the most difficult of the Six Big Losses to monitor and record. This is due to the reason that there is a portentous difference between the theoretical maximum speed and what people ring the maximum speed is. In most cases, in order to prevent other losses such as quality rejects and breakdowns, the production speed needs to be optimized. Losses due to reduce speed are therefore, often ignored or unde counterbalanceimated 21. It happens when the equipment runs slower than its optimal or maximum speed.Apart from that, reduced speed is the difference between designed speed and the actual operating speed 21. There are various reasons where equipment may be running at less t han its designed speed, for instance non-standard or difficult raw materials, history or past problems, mechanical problems, or fear of overloading the equipment. This loss of speed is actually converted into time during the OEE calculation. crushed StopsWe can also assume small stops as one of the most difficult of the Six Big Losses to monitor and record. Whenever a machine shows short interruptions and does not have a constant speed, this will not result in a smooth flow of production. Minor stoppages and the subsequent loss of speed can be the cause from products blocking sensors or products getting stuck in the conveyor belts. The machines effectiveness will be diminished drastically if these hitches occur frequently 21.The occurrence of these losses happens whenever equipment stops for a short time as the result of a temporary problem. As an example, a work-piece is jammed in a thrash about or when a sensor activates and shut down the machines, this will decidedly result in a minor stoppage. As soon as someone removes the jammed work-piece or resets the sensor instantly, it ranges normally again. These losses also include idling losses that occur when equipment continues to run without producing. Thus, since idling and minor stoppages interrupt jobs, therefore they can also be categorized as breakdowns. Despite that, the two are fundamentally different in that a minor stoppage and the duration are usually less than 10 minutes.2.7.1.3 Quality LossesA scrap is when the final product is not saleable, and the entire process has been wasted on product that will never make it to the customer. Thus, it is very essential to take into account the quality of the product while evaluating OEE. handiness and speed often has been the main focus, and quality is unexpended behind. The key to keep in mind is that without a good product, the rest of the operation is a white elephant. Generally, quality losses are generated during inauguration while the machine is ram ping up, during adjustment, or during normal production, as rejected/ outcaste product due to process instabilities.Startup RejectsProducts that do not meet the quality standards are called scraps, even if they can be sold as sub-spec. A specific type of quality loss is the startup losses where these losses occur due to whenStarting up of the machine the production is not shelter as soon as the machine starts and the first products do not meet the quality standards.The process of the machine at the end of a production run is no longer stable and the products no longer to be able to meet the specifications require.Quantities of products are no longer counted as part of the production order and consequently are considered as loss.These are usually hidden losses, which are often considered to be unavoidable. The scale of these losses can be surprisingly large 21. accepted adjustments and warm-up time is required for several equipments to obtain optimum output. Losses that happen in th e early stages of production during machine setup to stabilisation of product quality are called the startup losses. The losses differ with academic degree of stability of processing condition, operators technical skill, maintenance level on equipment, and many more. outturn rejectsA product that does not meet the quality specifications/standards for the first time, but can be reprocessed into good products is known as rework products. remolding products is not a disadvantage as the product can be sold to fit other demand needs. However, the product was not right first time and is therefore a quality loss just like scrap 21.Production rejects are classified as quality losses that are not caused by startup. These losses arise only when products produced are not conforming to the specifications. Parts that require rework of any kind should be considered reject and this happens during steady state production.Example of the Downtime loss, Speed loss, and Quality loss is depicted in th e following page.The Six Big Losses with three categories are shown in figure below. The following table shows how this Six Big Losses are categorized with examples given.Figure 2.3 potpourri of Six Big Losses.The table below lists the Six Big Losses, and show how they are relate to the OEE Loss categories. A typical major loss, the categories of OEE as well as examples of events is shown as followOEE LossCategorySix Big LossCategoryEvent ExamplesDown while LossBreakdowns Tooling Failures Unplanned Maintenance General Breakdowns Equipment FailureSetup and AdjustmentsSetup/ changeover Material Shortages Operator Shortages Major Adjustments Warm-Up clippingSpeed LossIdling and Minor stops Obstructed Product Flow gene Jams Misfeeds Sensor Blocked Delivery Blocked Cleaning/CheckingReduced Speed Rough Running Under Nameplate power Under Design Capacity Equipment Wear Operator InefficiencyQuality LossStart-up Losses shred Rework In-Process Damage In-Process Expiration Incorrect Asse mblyDefect Losses Scrap Rework In-Process Damage In-Process Expiration Incorrect AssemblyTable 2.1 The Six Big Losses in OEE2.8 OEE factorsAs explained in previous subsequent chapter, the OEE calculation is based on the three OEE factors. This comprises of availableness, Quality and act. They are as well referring as Effectiveness Factors. Here is how each of these factors is calculated.availablenessThe accessibility part of OEE represents the percentage of schedule time that the equipment is available to function 18. This Availability element is a measurement of the uptime that is designed to exclude the effects of performance, quality, and scheduled downtime events.Since Availability takes into account of Downtime loss, the formula is calculated as20Availability = Operation timePlanned Production timeWhere, Operation time = Planned production time Unscheduled DowntimeProduction time = Planned production time Scheduled DowntimeDowntime losses zero indicates the availability is coke%, where the gross operating time equals the available time for production. i.e. Operation time equals Planned Production time. Therefore, it can be said that coke% Availability delegacy the process has been running without any recorded stops.PerformancePerformance can be denoted as the ratio between gelt operating(a) while and direct condemnation. Since Performance takes into account of speed loss, the formula is calculated as22Performance = Net operate Time in operation(p) TimeThe Performance portion of OEE corresponds to the speed at which the machine runs as a percentage of its designed speed. This Performance element is a measurement of speed that is designed to exclude the effects of availability and quality 18. Performance does not penalize for rejects, which imply even if the work is rejected or rework, it will still be included in the planned and actual hours accordingly. Since Performance takes into account Speed Loss, the formula is calculated asPerformance = Ideal Cycle Timeoperating(a) Time / Total Pieces23Where, Ideal Cycle Time = the minimum cycle time that the process can be expected to achieve in optimal circumstances. It is at times called, Theoretical Cycle Time, Nameplate Capacity or Design Cycle Time. Since Run Rate is the reciprocal of Cycle Time, Performance can also be calculated asPerformance = Total Pieces / operating(a) TimeIdeal Run Rate24Performance is limited at 100%, to make sure that if an error is made in specifying the Ideal Cycle Time of Ideal Run Rate, the effect on OEE will be limited. Therefore, it can be said that 100% Performance convey the process has been consistently running at its theoretical maximum speed.Quality RateThe Quality portion of the OEE signifies the good units produced as a percentage of the total units produced 18. The Quality metric is a measurement of process yield that is designed to exclude the effects of availability and performance. Quality is the ratio of to the full Productive Tim e to Net Operating Time.Quality = to the full Productive Time / Net Operating Time25Quality = skinny Pieces / Total PiecesSince Quality takes into account of Quality Loss, the formula is calculated as26(Total no of units of processed products- No of units of no good products)/(total no of units of processed products). Thus, it can be said that 100% Quality means there is no rework or reject pieces. Therefore, since OEE takes into account all three OEE factors, the formula is calculated as27OEE = Availability x Performance x QualityTherefore OEE is the product of its effectiveness factors Availability, Performance andQuality.The study of each of these effectiveness factors will improve the Overall Equipment Effectiveness. at a lower place diagrams shows the three major elements of OEE together with formula calculated .Figure 2.4.Shows the formula on how to calculate OEEFigure 2.5Shows the OEE FactorsLossOEE FactorPlanned culminationNot included in OEE calculationDown Time LossAva ilability is the ratio of Operating Time to Planned Production Time (Operating Time is Planned Production Time less Down Time Loss).Calculated as the ratio of Operating Time to Planed Production Time.100% Availability means the process has been running without any recorded stops.Speed LossPerformance is the ratio of Net Operating Time to Operating Time (Net Operating Time is Operating Time less Speed Loss).Calculated as the ratio of Ideal Cycle Time to veridical Cycle Time, or alternately the ratio of Actual Run Rate to Ideal Run Rate.100% Performance means the process has been consistently running at its theoretical maximum speed.Table 2.1 indicates the 3 main factors of OEEQuality LossQuality is the ratio of Fully Productive Time to Net Operating Time (Fully Productive Time is Net Operating Time less Quality Loss).Calculated as the ratio of replete(p) Pieces to Total Pieces.100% Quality means there have been no reject or rework pieces.2.9 OEE Components of Plant Operating Time2. 9.1 Components of Plant Operating TimeIn order to establish an accurate measurement, OEE analysis begins with Plant Operating Time. Basically, this Plant Operating Time implies as the amount of time the facility is open and available for equipment process. It can also be refer as the maximum amount of time and is a constant. One day consists of 24 hours of 60 minutes. While, for one week, it consists of 7 days of 24 hours. Whereas, in one year consists of 52 weeks. At times, Plant Operating Time is also referred to as Theoretical Production Time. It consists of different losses like speed and quality loss as well as fully productive time2.9.1 Plant Production Time at a time a category of called Planned close down Down is subtracted from Plant Operating Time, the remaining available time is called Planned Production Time. The Planned Shut Down shall include any events that should be excluded from efficiency analysis since there was no intension of running production 22. For example, tea breaks, lunch breaks, scheduled maintenance or periods where there is nothing to produce. Nevertheless, Planned Production Time is also known as Available Production Time. OEE initiates with Planned Production Time and analyze efficiency as well as productivity losses that occur, with the aim of eliminating or reducing these losses. OEE starts with Plant Operating Time and end up with Fully Productive Time, screening the source of productive loss that occur in between.2.9.1.1 Operating TimeFrom Planned Production Time, the downtime loss is subtracted to gain Operating Time. The downtime losses inclusive of any events that stop planned production for an appreciable length of time (normally several minute-long decorous to log as a traceable event) 22. Examples of these include material shortages, equipment failures, and changeover time. Since it is also includes as type of downtime, the changeover time is included in OEE analysis. Even though it may not be possible to reduce 9 c hangeover times, however, it can be reduced in most cases. The remaining available time is called Operating Time and also known as Gross Operating Time 22.2.9.1.2 Net Operating TimeFrom the Operating Time, the speed loss is deducted to obtain Net Operating Time. The speed losses take account of any factors that cause the process to operate less than the maximum possible speed while running. Examples of these include machine wear, substandard materials, miss-feeds, and operator inefficiency.2.9.1.3 Fully Productive TimeAs for Net Operating Time, the Quality Loss is subtracted and the remaining available time is called the Fully Productive Time. These quality losses accounts for produced pieces that do not meet quality standards, together with pieces that require rework. The goal here is to maximize Fully Productive Time w