Equipment utilization rate. Efficiency of use of production equipment Calculation of the number of repairs and equipment downtime

And any business faces the task of reducing non-production time. If necessary equipment or the process does not work, this reduces the planned output, followed by a reduction in the profit and margin of the business.

The key question this metric helps answer is how effectively are we managing our processes or equipment?

Downtime is any production time during which a process or equipment is unavailable due to breakdowns (errors) or repairs (maintenance).

Equipment downtime is commonly associated with manufacturing industries; process downtime can occur in any industry. Take, for example, call centers, which can experience interruptions in the delivery of assistance over the phone, or hospitals, which are characterized by downtime of diagnostic equipment.

Downtime analysis gives companies the ability to evaluate the efficiency of internal production processes.

How to take measurements

Information collection method

The data for calculating a key performance indicator (KPI) comes directly from the process or equipment, or from reports.

Formula

The downtime of a process or equipment can be calculated using the relationship:

Downtime = (TAt / PPTt) × 100%

where TAt is the actual production time of the process or equipment for a given period t; PPT t is the planned production time of a process or equipment for a given period t.

KPI can be obtained in absolute terms:

Downtime = PPTt - TAt.

Downtime can be measured continuously (especially when automating a process) and serve as an indicator when a predetermined value has been reached. At the same time, information about downtime can be submitted on a monthly or quarterly basis.

The source of information may be the equipment itself, since many types production equipment track downtime automatic mode. The same applies to processes if there is an automatic monitoring system. In some cases, manual entries are required.

The cost of measuring downtime is modest and depends on the data already available. If equipment and processes generate downtime information automatically, the calculations are relatively simple. Costs increase with manual data collection.

Target values

The goal for this KPI should be a value equal to zero, subject to the exclusion or at least minimization of any unscheduled interventions in the production process - in particular, if the process or equipment does not operate around the clock, then maintenance can be carried out during non-production hours.

Example. Consider the radiology department of a hospital, which has two CT scanners for which we will determine the downtime. At least one of the tomographs must be ready to work around the clock, and during normal business hours (from 9.00 to 17.00) both devices must be ready to work.

Downtime is considered to be the time during which at least one tomograph is not ready for operation during normal business hours. Critical downtime is considered to be the time during which both tomographs are not ready for operation.

Let's look at an example based on one day.

Tomograph No. 1 was not working from 13.00 to 15.00 due to a breakdown and from 19.00 to 22.00 due to routine maintenance.

Tomograph No. 2 did not work from 19.00 to 20.00 due to a breakdown.

(2 hours / 8) × 100% = 25%, or 2 hours.

Downtime of tomograph No. 1 Downtime of tomograph No. 2 = 0%.

Critical downtime = 1 / 24 = 4.16% or 1 hour.

Notes

When measuring equipment downtime, you need to understand the cost component, such as the direct labor costs you incur by paying wages to the equipment operator when it is idle.

Competition, the desire to occupy new markets, increase business value and, finally, increase profits - all this gives impetus to initiatives to expand production, investing tens and hundreds of millions of rubles in new production equipment. However, when planning investments, not every manager can answer the question: are the available capacities being used effectively? The same question is appropriate to pose when the equipment has already been purchased and put into operation. Moreover, here you need not only to answer, but to justify your answer with quantitative indicators.

Naturally, the manager of the enterprise understands that the equipment operates under conditions of restrictions that prevent the increase in the efficiency of its use. Some of these restrictions are unavoidable: non-working hours (stops on weekends and holidays), scheduled stops (for re-adjustment, maintenance and preventive maintenance, loading of raw materials), loss of speed to bring stopped equipment to its nominal operating mode, etc. The easiest way is to accept these losses of time as a given and cross them off the calendar.

But this is where the problems that require attention lie. Did all the stops really take place as planned, or were there unplanned increases in their duration or number somewhere? If there were, then how to determine at what point in the technological process, when and for what reason?

Rice. 1. Real production time and lost production time

It is even more obvious that the lack service personnel, distractions during meetings, shortages of raw materials, power outages, defects and equipment failures lead to unscheduled downtime and reduced work speed technological systems, which means losses in production volumes. Moreover, in the absence of output during these time intervals, costs are still incurred (staff salaries, rent of space and equipment, etc.) and increase costs. It is also obvious that those periods when defects were made are equivalent to wasted time.

Each type of loss “pinches off” its contribution from the time during which the equipment could produce products. As a result, real production time correlates with calendar time as shown in Fig. 1. Does the manager who makes the decision to deploy additional capacity know about this?

Apparently, he guesses, but does not know exactly where and how much working time is “buried”, and how to extract it, how to dig up this kind of treasure hidden by a veil of uncontrollable factors. After all, the real production process involves tens and hundreds possible reasons loss of working time. How to identify them and how to manage them?

What is OEE?

Do you find it difficult to manage all your losses and their causes at the same time? - and don’t try to do this, but rather establish which types of losses have the greatest contribution, identify their causes and concentrate only on them. To paraphrase Pareto's rule, 80 percent of lost production time is due to 20 percent of the reasons. Accordingly, having dealt with the main problems, you can then move on to the next 20 percent, but at a new level of total losses.

The mention here of “species” already implies the presence of a certain classification and systematicity. The need to focus on the largest component of losses requires measurement. Indeed, what can be measured can be managed. And in this case, efficiency of measurement and response is also important. These needs are met by the internationally known indicator OEE - Overall Equipment Effectiveness, used to measure the overall efficiency of equipment.

The OEE indicator demonstrates that with the help of a simple calculation and analysis algorithm it is possible to obtain an answer to the most important question for an enterprise manager - how can one quickly and significantly increase product output without introducing additional capacity? The OEE indicator opens the “black box” of losses and allows you to capture problem areas production.

According to the definition, OEE takes into account three factors:

1. A - Availability - takes into account losses associated with equipment downtime (Down Time Loss).

A = (Actual time worked) / (Planned production time)

2. P - Performance - takes into account losses associated with a decrease in production speed (Speed ​​Loss).

P = (Quantity of products produced / Working time) / (Production rate per hour)

3. Q - Quality - takes into account losses associated with low quality products (Quality Loss).

Q = (Quantity of quality products) / (Quantity of products produced)

The resulting expression for calculating OEE is:

OEE = A * P * Q.

What is needed to measure OEE?

In order to obtain an OEE indicator, it is necessary to record equipment transitions from working to non-working states and vice versa during each work shift. In this case, the time spent in a particular state should be recorded.

In order to then analyze the causes of losses, the registration of these transitions must be accompanied by an indication of their reasons (a directory of reasons must be developed). Each shift must record the quantity of products produced, the amount of defects (or quality products), and the reasons for defects.

To compare work shifts, production lines or areas based on their contribution to the final OEE, the calculation of the indicator must be carried out with an appropriate sample of data - by shift, line, etc. As a rule, calculations are required for different production periods, etc. After corrective actions aimed at eliminating the causes of losses, it is necessary to monitor their effectiveness, that is, evaluate the new OEE value and analyze it in the necessary sections. Thus, it should be carried out continuous monitoring OEE. All information should be accumulated, stored and made available to the manager for analysis in a convenient form - in the form of histograms or graphs.

All this seems easy to do at first glance. But practical implementation calculating and monitoring OEE using paper media encounters serious difficulties as soon as we deal with more or less large-scale production. Primary automation tools, such as Excel tables, do not help either if you need to process large amounts of data.

Therefore, the task of OEE monitoring can be practically solved only in a corporate information system that will provide a unified OEE data environment for all involved persons - managers at different levels, production and maintenance personnel. The benefits that an information system provides are well known. This is a one-time data entry (there is no rewriting from one paper journal to another), one single copy of data for everyone (there is no multiplication of record copies fraught with contradictions), remote access to data (there is no stage of physical transportation of data from source to recipient), etc. d.

Moreover, in our opinion, efficient system OEE monitoring should have as its basis information system Maintenance and repair (IS MRO) equipment, and be like a superstructure over the IS MRO. Data from the MRO IS - on repairs performed, statistics on failures and damage to equipment and components, statistics on defects - is valuable information that should be used in the OEE monitoring system to identify the causes of losses.

That is, the enterprise must build an integrated equipment efficiency management system, which includes an MRO IS and an OEE monitoring system. In this case, it will be possible, by decomposing cause-and-effect relationships, to move from common reasons to particular ones, find the root causes of losses and make decisions aimed at eliminating them. For example, you can move along the information links between records: from identified unscheduled downtime - to the reason for the downtime (breakdown) - then to the nature of the breakdown (bearing failure) - then to the cause of the breakdown (lack of lubrication). In this case, the first two entries are made by production workers, and the last ones by maintenance personnel. When analyzed over a sufficiently long period of time, it is possible to identify recurring breakdowns and causes, repeated downtime due to them, etc.

Repair (service) service employees enter reports into the MRO IS on the work performed, indicating the spare parts and materials used, their cost, labor intensity of the work, and the cost of services from external organizations. By tracing the connection from breakdowns to causes and further to repair costs, it is possible to obtain an estimate not only of production losses due to downtime, but also to determine what direct costs the enterprise has incurred.

What does it look like?

The functions of users of the OEE performance monitoring system can be distributed as follows. Production personnel records in the system all equipment stops for a shift, indicating their reasons from the status directory - breakdown, lack of supply of raw materials, damage to packaging (Fig. 2), etc. For the operational state, the operator records the set operating speed production line for subsequent analysis of the distribution of product output productivity. At the end of the shift, the operator registers in the system the number of products produced and defects, as well as the rate of production speed.

Rice. 2. Chain of equipment states for which OEE is measured

Rice. 3 Summary of defects indicating causes and consequences
(Click on the image to enlarge it)

Repair personnel, whose goal is to ensure the operability (readiness) of production equipment, uses the defect log in the MRO IS (Fig. 3). All failures and damage are recorded, their types and causes are specified. Work is planned to eliminate them. Accumulated statistics on the distribution of defects by causes, consequences and criticality are used to plan preventive maintenance and timely provision of spare parts and materials. Reports on maintenance and repairs performed are entered into the database, which, along with registered defects, are stored in electronic equipment forms and work logs. This data contains information about labor costs, replacement parts, causes of defects, actual and planned costs of work, etc. and can be printed out of the system.

Rice. 4. Indicators of distribution of working time use per shift
(Click on the image to enlarge it)

The middle manager receives operational data for the shift on indicators of lost working time and distribution data by production speed (Fig. 4), evaluates OEE indicators, analyzes the causes of losses, plans measures to improve the equipment maintenance process, and monitors the implementation of planned activities.

Top management receives operational data on OEE indicators for any period (Fig. 5), evaluates OEE indicators, analyzes the causes of losses using Pareto charts (Fig. 6), demonstrating the main causes of lost working time.

Rice. 5. Summary OEE indicators for the selected period

Thus, the OEE technique makes it possible to systematize the factors that reduce the efficiency of equipment, see the degree of their impact and, as a result, influence the result not at the level of assumptions and intuition, but using a modern and effective management tool. For anyone large enough and modern production this is extremely important.

Rice. 6. Diagram of causes of downtime

Literature:

1. Hansen, Robert C. Overall Equipment Effectiveness: a powerful production/maintenance tool for increased profits. Industrial Press, 2001. ISBN 0-8311-3138-1.

2. Hansen, Robert C. Unleashing the Power of OEE//Maintenance technology articles. - 1998. - June. (www.mt-online.com).

3. Kryukov I.E., Antonenko I.N. Automation of repair and maintenance management at a food industry enterprise// Food industry. — 2009. -№5. — P. 22-24.

Of great importance is the development and implementation of organizational measures to increase and improve the use of production capacity, improving the organization of equipment repairs, ensuring a reduction in equipment downtime, increasing labor discipline of workers, etc.

The time for repairs and inspections of equipment in discontinuous and continuous production is determined by standard equipment according to uniform standards. These standards specify the frequency of repairs, the duration of equipment downtime for repairs and the labor intensity of repairs. For the rest of the equipment - by analogy or on the basis of progressive indicators of enterprises. If the actual results of the work of the best repair teams at the enterprise provide a reduction in equipment downtime for repairs compared to established industry standards, then these progressive indicators should be taken into account when calculating the time fund.

Establishment of equipment downtime for repairs based on the maintenance schedule

Standards for the duration of equipment downtime for repairs include the time for preparatory, repair and final work.

Reducing the duration of equipment downtime during repairs is achieved through timely and complete technical and material preparation repair work, ensuring the continuity of their implementation in accordance with the developed plan for organizing repairs using maps of the scientific organization of labor compiled for the repair of large units and technological lines for the use of the most advanced methods and techniques for performing repair work using special equipment and means of mechanization of the organization of repair work, ensuring maximum compaction of the repair process in time, the use of network schedules for this purpose, providing repair work with qualified personnel and the participation of operating personnel in the repair, creating a material and moral interest for the performers of repair work in completing them ahead of schedule with a high quality of repair.

The industry is faced with the task of increasing the shift ratio and eliminating equipment downtime.

The duration of equipment downtime for repairs is determined by the total duration of the preparatory (Pp), repair (Pr) and final (P3) periods

Repair costs depend on the type of process plant; they are the largest item in processing costs. Each day of equipment downtime for repairs is associated with a significant decrease in production output. Therefore, speeding up and reducing the cost of repair work is of current importance.

The difference between the calendar and effective (planned) time funds is the duration of planned downtime. In fact, as a rule, there are also unscheduled equipment downtime as a result of unforeseen reasons - accidents, deficiencies in production organization, etc. Therefore, the actual time worked (Tfr) will be somewhat less than the effective time fund (Teff).

In addition to planned ones, unscheduled equipment downtime is also possible. Typically, these downtimes are the result of deficiencies in production, supply and labor organization. The goal is to completely eliminate unscheduled downtime and minimize planned downtime.

Downtime data technological installations show that in the total amount of downtime, 48% or more is downtime during major and current repairs. Therefore, the development of measures aimed at reducing equipment downtime during repairs has great importance to increase the coefficient of extensive use of technological installations. There is also a large amount of downtime of technological installations due to organizational reasons (lack of raw materials, electricity, tanks, etc.). -

Leveling production by volume is the most an important condition application of the kanban system and minimal loss of workers’ time, reducing equipment downtime.

And this approach has a very serious basis. When switching to automated equipment, the number of service personnel is significantly reduced and each worker has to control a large group of machines. If cleaning on such equipment is technically difficult to implement or is difficult to organize, then this will certainly cause various disruptions in the technological process, which sooner or later will cause a decrease in the quality of processing, the appearance of defects, costly equipment downtime.

Fig, 10.3. Dependence of material and cost indicators of repair production on the level of in-plant centralization of repair personnel / - equipment downtime during repairs // - cost of capital repairs I EP equipment /// - output per repairman IV - labor intensity of capital repairs V - dynamics of plan implementation overhaul  

Reducing equipment downtime during repairs by reducing repair time due to their specialization and rational organization.

As experience shows, at present there is a lot of equipment downtime at electrical plants for organizational reasons. In this regard, further improvement of organization and management in the industry is necessary.

The increasing importance of repair and modernization of fixed assets, especially equipment, requires constant improvement of its organization. The main objectives of organizing repairs are to increase the level of operational readiness of fixed assets; reduce equipment downtime during repairs; reduce labor and material costs associated with performing maintenance and repair work on fixed assets; improve the quality of their maintenance and repairs, ensuring a reduction in the need for repairs; (if necessary) major repairs of equipment with its modernization, mechanization of repair work and increasing the level of labor productivity of repair personnel.

As a rule, it is preferable to round down the service rate, since, firstly, equipment downtime in most cases is associated with greater losses than work downtime, and secondly, worker downtime can also be used for rest, personal needs or work maintenance. places.

The former three-link system of machines - engine, transmission mechanism, working machine - has turned into a four-link system, which also includes devices for automatic regulation and control of production processes. This includes measuring and control electrical, electronic, pneumatic and hydraulic devices, remotes automatic control, means of dispatch control, computer equipment, etc. The rhythm of the production process, strict adherence to the regime, reduction of equipment downtime depend on this group of fixed assets, and hence -

Determination of equipment downtime rates in robotic technological complexes

Option No. 8

Completed by: student of group 03-311 /Silevich E.A./

Consultant: Associate Professor 307 /Grachev V.V./

Moscow 2013.

Goal of the work- Based on the theory of queuing, determine the average downtime of machines and manipulators, the downtime rate due to multi-machine service.

General information

The problem of complex automation of multi-item serial production is effectively solved by creating standard robotic technological complexes (RTC). They represent the totality of the unit technological equipment(automatic machines), industrial robots and equipment that operate autonomously and carry out multiple cycles.

The efficiency of robots increases when servicing automatic machines in groups.

Serving some machines with one handling device reduces costs and allows these devices to partially perform transportation functions. In this case, losses arise while the machine is waiting for service, if at the same time there is a need for new workpieces at several positions.

Waiting time for manipulating device service
leads to losses, which are determined approximately based on theory
mass service.

Time for performing some regulated work in technological process is called the norm of piece time T piece:

where t 0 is the main time spent directly on
shaping the part (deformation, removal and application
material, assembly, installation, etc.);

t in - auxiliary time time spent on installation, securing the workpiece, removing the part, time for approaching and retracting tools, etc.;

t org - organizational service time (supplying the workplace with workpieces, components, tools, removing finished products etc.);

t tech - time for workplace maintenance (turning on equipment, warming up, adjusting devices, turning off equipment, cleaning it, etc.);

t per - time of breaks in work, in relation to conveyor production.

For automatic equipment The time it takes to complete one operation is called operational time T op or cycle time T c:

The machine system is closed system waiting for the M/M1 form with internal organization FIFO (first in, first out).

Each service request is satisfied when a manipulator services another machine. The application is put on the queue, and the machine waits until the manipulator is free.

The designation M/M1 indicates that the nature of requests and the servicing process correspond to a Markov process, and the number of servicing devices is equal to one.

Average cycle time and average service time are due to the fact that service orders are random in nature. The rate of receipt of service orders per unit time is equal to:

where is the average cycle time for parts processed in the machine system:

where T rev is the service time of one machine.

For calculations, it is convenient to introduce the dimensionless coefficient ρ - the ratio of the intensity of receipt of requests to the average intensity of service:

where k is the number of orders from machines for their maintenance.

The Markov process means that the random issuance of service requests does not depend on previous requests.

In the system, the number of requests for service can be equal to k = 0, 1, 2, ..., m. Possible states (E) of the system:

E 0 (k=0) - all machines are working, the manipulator is standing.

E 1 (k=1) - all machines except one are working, the manipulator serves the machine from which the request was received.

E m (k=m-1) – all machines are standing, one machine is serviced by a manipulator, the rest are waiting in line for order execution.

Probability that all machines are working (no orders):

It is convenient to use the recurrent formula:

Number of machines waiting in line for service:

Average underload of one machine:

Rice. 2. Graphs of the dependence of P k, A s, A m, K on the amount of equipment

Exercise

For a machine system, including 3 machines and one service manipulator, determine the average downtime of the machines and manipulator, the downtime rate due to multi-machine maintenance.

Initial data

Calculation of required parameters

1. We define the coefficient ρ as the ratio of the intensity of requests received to the average intensity of service:

2. Determine P 0 - the probability that all machines are working and the manipulator is standing:

3. Probability of receiving k requests for service:

Examination:

The calculations were carried out correctly.

4. Determine the average number of machines awaiting service:

5. We determine the machine downtime rate due to waiting during multi-machine maintenance:

6. Probability of machine operation in given time:

those. Average machine utilization is 90.3%.

7. Probability of the manipulator working at a given time:

Conclusions:

1. The coefficient of equipment utilization by volume of work (integral load coefficient) reflects both the time and the degree of use of its capacity and is equal to the ratio of the volume of products actually produced on it to the planned volume that should be obtained when working without downtime and with the installed capacity. Increasing the equipment utilization rate is the most important prerequisite for intensifying production and increasing production output at existing facilities.

Instructions

Select a fixed asset (or a group of them) and evaluation parameters to analyze the efficiency of use. The use of workshop machines can be assessed by the time they operate or by the volume of products produced, the use of trucks by the number of tons transported, etc. Suppose it is necessary to calculate the utilization rate of a weaving workshop based on the time they operate. There are ten machines in the workshop, staff in two twelve-hour shifts.

Determine the planned working time fund for the analyzed period, taking into account the established operating mode. To calculate it, you can use a production time sheet if the enterprise operates on a five-day schedule. working week. If shifts are established in production, then the planned working hours are calculated based on the approved shift schedules. IN in this example The planned load of one machine for a month will be equal to: 30 days per 24 hours = 720 hours.

Determine the number of hours of actual operation of the looms in the workshop during the period. To do this, you will need timesheet data. Find the total number of hours worked by the shop staff. Let the workers of the weaving shop work 6,800 man-hours in a month, which corresponds to the actual operating time of the machines.

Calculate the utilization rate of the weaving workshop equipment using the formula - Ki = (Fr/S)/Fp, where: Fr - actual amount of time worked by all machines, hour, C - number of machines in the workshop, pcs, Fp - planned working time fund, hour. In this example, the equipment utilization factor will be equal to: 6,800/10/720= 0.94. Consequently, the looms of the weaving workshop were used at 94% for the month. The remaining 6% is his downtime. Similarly, you can calculate the utilization rate of any fixed asset (or group of assets) for the period of interest to you.

note

To increase the efficiency of equipment use, it is necessary to reduce downtime. To do this, you need to use high-quality raw materials, pay attention to improving the qualifications of personnel, and replace worn-out equipment with new ones.

Sources:

• Enterprise economy
• Coefficient financial independence

A coefficient is a certain indicator expressed in relative values. It can reflect the speed of development of any action, the relationship of various phenomena, the degree of use of resources and many other aspects that can be compared and assessed. Demand represents certain needs, for anything, mediated and limited by some factors. Considering the above, the demand coefficient as an indicator can be used in any area of ​​life, both material and intangible.

Instructions

In order to determine the demand coefficient, it is necessary to know what kind of demand it is necessary to determine what factors influence demand indicators and what their numerical expression is. It is also important to know and be able to apply various demand coefficients. Initially, it is necessary to determine which demand coefficient will be calculated. This could be demand and services, demand for money, demand for loads and many, many other categories.

Having decided on the type of demand, it is necessary to establish which factors and to what extent influence the determination of the demand coefficient. This requires either monitoring current processes that affect the demand coefficient, or obtaining already known values. To obtain already known quantities, there are various kinds of reference books.