PPR schedule for electrical installations. How to draw up a PPR schedule for electrical equipment

PZ No. 4. Calculation of equipment maintenance schedule.

Task number 1. The operating time of the pump between overhauls is 8640 hours, the average - 2160 hours, the current ones - 720 hours. The actual number of days of work per year is 360. The number of work shifts is 3, the duration of the shift is 8 hours. By the beginning of the year, the equipment had run after overhaul 7320 hours, average - 840 hours, current - 120 hours. Make a schedule for the shutdown of the pump for the year.

Decision.

To schedule a pump shutdown for a year:

1. Number of working days in a month: 360 / 12 = 30 days

2. Month of shutdown for repairs:

Capital (8640 - 7320) / 3 * 8 * 30 = 1.8 months, we accept February.

Current (2160 - 840) / 3 * 8 * 30 = 1.8 months, we accept February

RTO (720 - 120) / 3 * 8 * 30 \u003d 0.8 months, we accept January.

3. We determine after how many months it is necessary to make subsequent repairs:

Capital 8640 / 3 * 8 * 30 = 12 months, we accept 12 months, i.e. next year;

Current 2160 / 720 = 3 months, we accept in 3 months, those in February, May, August, November.

PTO 720 / 720 = 1 month, accepted after 1 month, i.e. every month except February, May, August and November.

4. We draw up a pump PPR schedule:

Month: Jan. Feb. March Apr may june july aug. sept. oct. Nov. dec

Type TO TO TO TO T TO TO TO T TO TO T TO

repair

Task 2. There are 20 dryers in the PVC resin production workshop. The actual operating time of one dryer per year is 6480 hours, the duration of the overhaul cycle is 8640 hours, from overhaul to current repairs is 4320 hours, between maintenance and repair is 864 hours. The calendar operating time of the equipment per year is 8640 hours. Determine the number of major, current repairs and maintenance of dryers per year.

Methodical instructions.

The required number of repairs per year for each type and type of equipment is determined by the formula:

n rem. = Ood.rev. * Tfact * n in. rem. / tc, where

Ood.ob. - the number of units of the same type of equipment in operation;

Tts - the duration of the overhaul cycle, hour;

Tfact - the actual operating time of the equipment, hour;

n in. rem. - the number of all repairs (major, medium, current) of the overhaul cycle.

The number of repairs of each type is determined by the formulas:

capital

n cap. = Tk / Tc

current

n cf. = Tk / Tc.t. - one

repair and maintenance services

n pto \u003d Tk / Tc.t. - ∑ (cap. + current), where

Tk is the calendar operating time of the equipment, hour.

Tc.t. - the duration of the overhaul period from overhaul to current repairs, hour;

∑ (cap. + current ..) - the amount of capital and current repairs.

Task 3. Calculate the number of compressor repairs based on the following data: the number of compressors - 8, the duration of the overhaul cycle = 8640 hours, the overhaul period between major repairs - 7130 hours, between the current ones - 2160 hours, between RTO - 720 hours. Actual number of days of operation per year - 358, number of shifts - 3, shift duration - 8 hours.

Methodical instructions.

To complete the task, use the formulas for the calculation given in guidelines to task 2.

Task 4. Make a schedule PPR equipment according to the data below:

Indicators	Option 1	Option 2	Option 3
Equipment	Compressor	Dryer	Autoclave
Working time between repair hours, hours
Capital	7130	14700	8238
Current	2160	2880	2880
RTO
Actual number of days worked per year
Number of shifts
Duration working days, hours
Continued mileage rev. after rem. by the beginning of the year,
Capital	5310	12200	7310
current			1950
RTO

Methodical instructions.

To complete the task, use the formulas for the calculation given in the guidelines for task 1.

Task 5. Determine the downtime of equipment in repair according to the data below:

Indicators	Pump	Distillation column	Bake
Labor intensity of repair, man-hour
number
riggers
locksmiths
welders
Working hours
Number of shifts

Guidelines

The downtime is equal to the quotient of the division: the numerator is the complexity of the repair, the denominator is the product of the number of repairmen times the working day and the rate of completion of the norm.

The PPR system is based on the following basic principles:

 the implementation of preventive work should be carried out strictly according to pre-compiled calendar schedules;

 when justifying the frequency of preventive maintenance, it is necessary to take into account environmental conditions, temporary modes of operation of equipment, the degree of responsibility of technological processes, etc.;

 the volume and labor intensity of preventive maintenance performed are provided on an average (enlarged basis) and are specified in each specific case depending on the technical condition of the equipment;

 The design of the equipment must comply with the environmental conditions and the mode of operation, based on the requirements of regulatory documents.

Scheduled preventive maintenance is a set of works aimed at maintaining and restoring equipment performance. Depending on the nature and degree of equipment wear, on the volume, content and complexity of preventive maintenance, it includes overhaul maintenance, current, medium and overhaul s.

Interrepair maintenance is preventive in nature. It consists of regularly cleaning and lubricating the equipment, inspecting and checking the operation of its mechanisms, replacing parts with a short service life, and eliminating minor faults. These works, as a rule, are carried out without stopping the equipment, during its current operation.

Current repair is a complex repair work carried out between two regular overhauls and consisting in the replacement or restoration of individual parts. Current repairs are carried out without complete disassembly of the equipment, but it requires a short shutdown and decommissioning of the equipment with de-energization. At current repair equipment, external inspection, cleaning, lubrication, checking the operation of mechanisms, repair of broken and worn parts, for example, inspection and cleaning of the generator without excavating the rotor, varnishing the frontal parts, wiping insulators, inspection and cleaning of inputs at transformers and switches without changing them, etc. d.

Thus, current repairs are carried out to ensure or restore the operability of electrical equipment by eliminating failures and malfunctions that occur during its operation. During the current repair, the necessary measurements and tests are carried out to identify equipment defects at an early stage of their development. Based on measurements and tests, the scope of the upcoming overhaul is specified. Current repairs are usually carried out at least once every 1-2 years.

During a medium repair, individual units are disassembled for inspection, cleaning of parts and elimination of detected malfunctions, repair or replacement of wear parts or units that do not ensure normal operation of the equipment until the next overhaul. Average repairs are carried out with a frequency of no more than 1 time per year.

During a major overhaul, equipment is opened and revised with a thorough internal inspection, measurements technical parameters and troubleshooting of found faults. Overhaul is carried out at the end of the overhaul period established for each type of equipment. During the final repair, all worn parts are replaced or restored, individual elements and equipment units are modernized. These works require the dismantling of units, complete external and internal repairs with checking the condition of components and parts, a significant number of highly skilled workers, a long shutdown of electrical equipment, a large amount of testing and complex devices. The main electrical equipment is subject to major repairs at a certain time.

Unlike current repairs, medium and capital repairs are aimed at restoring a partially or completely used up mechanical and switching resource of equipment.

Upon completion of the repair, the equipment is assembled, adjusted and tested. The main equipment of power plants and substations after preliminary acceptance from repair is checked in operation under load for 24 hours.

The conclusion about the suitability of the equipment for operation is made on the basis of a comparison of the test results with current standards, the results of previous tests, as well as measurements obtained on the same type of equipment. Non-transportable equipment is tested in mobile electrical laboratories.

In addition to scheduled preventive repairs in the practice of power supply systems, there are unplanned repairs: emergency and recovery and unscheduled. The task of emergency repair is to eliminate the consequences of an accident or eliminate damage that requires immediate shutdown of the equipment. In case of emergency (fire, insulation overlap, etc.), the equipment is stopped for repairs without the permission of the dispatcher.

The terms for major repairs of the main equipment of power facilities are as follows:

Turbine generators up to 100 MW Turbine generators over 100 MW Hydrogenerators Synchronous compensators Main transformers, reactors and auxiliary transformers Oil circuit breakers Load break switches, disconnectors, earthing knives Air circuit breakers and their drives Compressors for air circuit breakers Separators and short-circuiters with drives Condenser units Rechargeable batteries

1 time in 45 years 1 time in 3-4 years 1 time in 4–6 years 1 time in 4–5 years The first time not later than 8 years after putting into operation, in the future - as needed, depending on the results of measurements of their condition 1 time in 6–8 years 1 time in 4–8 years 1 time in 4–6 years 1 time in 2-3 years 1 time in 2-3 years 1 time in 6 years Not later than 15 years after the start of operation

Unscheduled repairs are agreed with the system dispatcher and are made out with a corresponding application. They are carried out to eliminate various malfunctions in the operation of the equipment, as well as after the switching resource has been triggered. So, depending on the type, circuit breakers with a voltage of 6 kV and above are put into unscheduled repair after switching off 3-10 short circuits at the rated breaking current.

Scheduled preventive maintenance is the simplest and most reliable way to schedule repairs.

The main conditions that ensure planned and preventive relations regarding the repair of equipment are as follows:

The main need for electrical equipment for repair is satisfied by scheduled repairs performed after a specific number of hours worked by it, due to which a periodically repeating cycle is formed;

Each scheduled preventive repair of electrical installations is carried out to the extent necessary to eliminate all existing defects, as well as to ensure the natural operation of the equipment until the next scheduled repair. The term of scheduled repairs is determined according to the established periods;

The organization of preventive maintenance and control are based on the usual scope of work, the implementation of which ensures the operable condition of the equipment;

The normal scope of work is determined by the established optimal periods between scheduled periodic repairs;

Between planned and periodic periods, electrical equipment undergoes scheduled inspections and checks, which are a means of prevention.

The frequency and alternation of scheduled equipment repair depends on the purpose of the equipment, its design and repair features, dimensions and operating conditions. Preparation for a scheduled repair is based on the specification of defects, the selection of spare parts and spare parts that will need to be replaced during the repair. An algorithm for this repair is specially created, which ensures uninterrupted operation during the repair. This approach to preparation makes it possible to carry out a complete repair of equipment without disturbing the usual work of production.

Well-planned preventive maintenance includes:

Planning;

Preparation of electrical equipment for planned repairs;

Carrying out scheduled repairs;

Carrying out activities related to scheduled maintenance and repair.

The system of planned preventive maintenance of equipment includes a couple of stages:

1. Stage overhaul

It is carried out without disrupting the operation of the equipment. Includes: systematic cleaning; systematic lubrication; systematic examination; systematic adjustment of the operation of electrical equipment; replacement of parts that have a short service life; fixing minor problems.

In other words, this is preventive maintenance, which includes daily inspection and maintenance, and at the same time, it must be properly organized in order to maximize the life of the equipment, maintain high-quality work, and reduce the cost of scheduled repairs.

The main work performed at the overhaul stage:

Tracking the state of equipment;

Enforcement by employees of the rules of appropriate use;

Daily cleaning and lubrication;

Timely elimination of minor breakdowns and adjustment of mechanisms.

2. Current stage

Scheduled preventive maintenance of electrical equipment is most often carried out without dismantling the equipment, only its operation stops. Includes the elimination of breakdowns that occurred during the period of work. At the current stage, measurements and tests are carried out, with the help of which flaws in equipment are detected at an early stage.

The decision on the suitability of electrical equipment is made by repairmen. This decision is based on a comparison of test results during scheduled maintenance. In addition to scheduled repairs to eliminate defects in the operation of equipment, work is carried out outside the plan. They are carried out after the exhaustion of the entire resource of the equipment.

3. Stage middle

It is carried out for the full or partial restoration of obsolete equipment. Includes disassembly of units, designed to view, clean the mechanisms and eliminate the identified defects, replace some wear parts. The middle stage is carried out no more than once a year.

The system at the middle stage of preventive maintenance of equipment includes setting the cycle, volume and sequence of work in accordance with the regulatory and technical documentation. The middle stage affects the maintenance of the equipment in good condition.

4. Overhaul

It is carried out by opening electrical equipment, its full check with inspection of all details. It includes tests, measurements, elimination of identified faults, as a result of which the modernization of electrical equipment is carried out. As a result of the overhaul, the technical parameters of the devices are completely restored.

Major overhaul is possible only after the overhaul stage. To carry it out, you must do the following:

Draw up work schedules;

Carry out preliminary inspection and verification;

Prepare documents;

Prepare tools and necessary replacement parts;

Carry out fire fighting measures.

Major overhaul includes:

Replacement or restoration of worn mechanisms;

Modernization of any mechanisms;

Perform preventive checks and measurements;

Carrying out minor repairs.

Malfunctions found during equipment checks are eliminated during subsequent repairs. And breakdowns of an emergency nature are eliminated immediately.

Everyone separate view equipment has its own frequency of scheduled preventive maintenance, which is regulated by the Rules technical operation. All activities are reflected in the documentation, a strict record of the availability of equipment, as well as its condition, is kept. According to the approved annual plan a nomenclature plan is created, which reflects the implementation of capital and current repairs. Before starting current or major repairs, it is necessary to specify the date of installation of electrical equipment for repairs.

Planned preventive maintenance year- this is the basis that serves to draw up a budget plan for the year, developed 2 times a year. The sum of the year of the budget plan is divided into months and quarters, it all depends on the period of the overhaul.

Today, for the system of preventive maintenance of equipment, computer and microprocessor technology (structures, stands, installations for diagnostics and testing) are most often used, which affects the prevention of equipment wear, lower repair costs, and also helps to increase operational efficiency.

The system of scheduled preventive repairs or the PPR system, as it is customary to call this method of organizing repairs for short, is a fairly common method that originated and received wide use in countries former USSR. The peculiarity of such a "popularity" of this type of organization of the repair economy was that it fit rather harmoniously into the planned form of economic management of that time.

Now let's look at what PPR (planned preventive maintenance) is.

System of planned preventive maintenance (PPR) of equipment– system of technical and organizational measures aimed at maintaining and (or) restoring operational properties technological equipment and devices as a whole and (or) individual pieces of equipment, structural units and elements.

Enterprises use various varieties systems of planned preventive repairs (PPR). The main similarity in their organization is that the regulation of repair work, their frequency, duration, costs for these works is planned. However, various indicators serve as indicators for determining the timing of scheduled repairs.

PPR classification

I would single out several varieties of the preventive maintenance system, which have the following classification:

regulated PPR (scheduled preventive maintenance)

• PPR by calendar periods
• PPR for calendar periods with adjustment of the scope of work
• PPR for operating time
• PPR with regulated control
• PPR by operating modes

PPR (scheduled preventive maintenance) according to the state:

• PPR for acceptable level parameter
• PPR according to the permissible level of the parameter with the adjustment of the diagnostic plan
• PPR on the admissible level of the parameter with its prediction
• PPR with control of the level of reliability
• PPR with a forecast of the level of reliability

In practice, the system of regulated preventive maintenance (PPR) is widespread. This can be explained by greater simplicity, compared with the state-based PPR system. In the regulated PPR, the binding goes to calendar dates and it is simply accepted that the equipment operates throughout the entire shift without stopping. In this case, the structure of the repair cycle is more symmetrical and has fewer phase shifts. In the case of organizing a PPR system according to some acceptable parameter-indicator, it is necessary to take into account a large number of these indicators specific to each class and type of equipment.

Benefits of using a PPR system or preventive maintenance of equipment

The system of planned preventive maintenance of equipment (PPR) has a large number of advantages that determine its widespread use in industry. As the main ones, I would single out the following advantages of the system:

• control over the duration of overhaul periods of equipment operation
• regulation of equipment downtime for repairs
• forecasting the cost of repairing equipment, components and mechanisms
• analysis of the causes of equipment failure
• calculation of the number of repair personnel depending on the repair complexity of the equipment

Disadvantages of the PPR system or preventive maintenance of equipment

Along with the visible advantages, there are a number of disadvantages of the PPR system. I will make a reservation in advance that they are mainly applicable to enterprises of the CIS countries.

• lack of convenient tools for planning repairs
• complexity of labor costs calculations
• the complexity of taking into account the parameter-indicator
• the complexity of the operational adjustment of the planned repairs

The above shortcomings of the PPR system relate to certain specifics of the technological equipment park installed at CIS enterprises. First of all, this is a large degree of equipment wear. Often the wear of equipment reaches 80 - 95%. This significantly deforms the system of preventive maintenance, forcing specialists to adjust the PPR schedules and carry out a large number of unplanned (emergency) repairs, significantly exceeding the normal amount of repair work. Also, when using the method of organizing the PPR system by operating time (after a certain time of equipment operation), the labor intensity of the system increases. In this case, it is necessary to organize accounting of actually worked machine hours, which, together with a large fleet of equipment (hundreds and thousands of units), makes this work impossible.

The structure of repair work in the PPR system of equipment (scheduled preventive maintenance)

The structure of repair work in the equipment maintenance system is determined by the requirements of GOST 18322-78 and GOST 28.001-78

Despite the fact that the PPR system assumes an accident-free model for the operation and repair of equipment, in practice it is necessary to take into account unscheduled repairs. They are most often caused by poor technical condition or an accident due to poor quality

How to draw up a PPR schedule for electrical equipment?

How to draw up an annual schedule for the maintenance of electrical equipment? I will try to answer this question in detail in today's post.

It's no secret that the main document for the repair of electrical equipment is the annual schedule of preventive maintenance of electrical equipment, on the basis of which the need for repair personnel, materials, spare parts, components is determined. It includes each unit subject to major and current repairs of electrical equipment.

To draw up an annual preventive maintenance schedule (PPR schedule) for electrical equipment, we need standards for the frequency of equipment repairs. These data can be found in the manufacturer's passport data for electrical equipment, if the plant specifically regulates this, or use the "System Maintenance and repair of power equipment. I use A.I. FMD in 2008, therefore, I will refer to this source further.

Download A.I. foot and mouth disease

So. Your household has a certain amount of power equipment. All this equipment must be included in the PPR schedule. But first a little general information what is the annual PPR schedule.

Column 1 indicates the name of the equipment, as a rule, brief and understandable information about the equipment, for example, name and type, power, manufacturer, etc. Column 2 - number according to the scheme (inventory number). I often use numbers from electrical single-line diagrams or from technological ones. Columns 3-5 indicate the resource standards between major repairs and current ones. Columns 6-10 indicate the dates of the last major and current repairs. In columns 11-22, each of which corresponds to one month, symbol indicate the type of planned repair: K - capital, T - current. In columns 23 and 24, respectively, the annual downtime of equipment in repair and the annual fund of working hours are recorded. Now that we have considered general provisions about the PPR schedule, consider a specific example. Let's assume that in our electrical facilities, in building 541, we have: 1) a three-phase two-winding oil transformer (T-1 according to the scheme) 6 / 0.4 kV, 1000 kVA; 2) pump motor, asynchronous (designation according to the scheme H-1), Рн=125 kW; Step 1. We enter our equipment into the empty form of the PPR schedule.

Step 2 At this stage, we determine the resource standards between repairs and downtime. a) For our transformer: open the reference book p. 205 and in the table "Standards for the frequency, duration and complexity of repair of transformers and complete substations" we find a description of the equipment that fits our transformer . For our power of 1000 kVA, we select the values ​​​​of the frequency of repairs and downtime during major and current repairs, and write them down in our schedule.

b) For an electric motor according to the same scheme - page 151 Table 7.1 (see figure).

We transfer the found standards in the tables to our PPR schedule

Step 3 For the selected electrical equipment, we need to determine the number and type of repairs in the coming year . To do this, we need to determine the dates of the last repairs - major and current. Suppose we are making a schedule for 2011. The equipment is operational, the dates of repairs are known to us . For T-1, the overhaul was carried out in January 2005, the current one - January 2008 . For the pump engine N-1, the capital one is September 2009, the current one is March 2010. We enter this data into the chart.

We determine when and what types of repairs are due for the T-1 transformer in 2011. As we know there are 8640 hours in a year. We take the found resource standard between major repairs for the T-1 transformer 103680 h and divide it by the number of hours in a year 8640 h. We calculate 103680/8640 = 12 years. Thus, the next overhaul should be carried out 12 years after the last overhaul, and since. the last one was in January 2005, which means that the next one is planned for January 2017. For current repairs, the same principle of operation: 25920/8640=3 years. The last maintenance was carried out in January 2008, thus. 2008+3=2011. The next current repair is in January 2011, it is for this year that we draw up a schedule, therefore, in column 8 (January) we enter “T” for the T-1 transformer.

For the electric motor we get; major repairs are carried out every 6 years and are planned for September 2015. The current one is held 2 times a year (every 6 months) and, according to the latest current repairs, we plan for March and September 2011. Important note: if the electrical equipment is newly mounted, then all types of repairs, as a rule, "dance" from the date the equipment was put into operation. Our chart looks like this:

Step 4 Determine the annual downtime for repairs . For a transformer, it will be equal to 8 hours, because. in 2011, we planned one current repair, and in the resource norms for current repairs, the denominator is 8 hours . For the N-1 electric motor in 2011 there will be two current repairs, the downtime rate in the current repair is 10 hours. Multiply 10 hours by 2 and get an annual downtime equal to 20 hours. In the column of the annual working time fund, we indicate the number of hours that this equipment will be in operation, minus downtime for repairs. We get the final form of our graph.

An important note: at some enterprises, power engineers in their annual PPR schedules, instead of the last two columns of annual downtime and the annual fund, indicate only one column - “Labor intensity, man * hour”. This labor intensity is calculated according to the number of pieces of equipment and the norms of labor intensity of one repair. This scheme is convenient when working with contractors performing repair work. Do not forget that the dates of repairs must be coordinated with the mechanical service and, if necessary, the instrumentation service, as well as with other structural units that are directly related to the repair and maintenance of related equipment. If you have any questions about the preparation of the annual PPR schedule, ask questions, I will try, if possible, to answer them in detail.