Planned preventive maintenance is the easiest and most reliable way to plan repairs.

The main conditions ensuring the preventive relations regarding the repair of equipment are the following:

The main need for electrical equipment to be repaired is satisfied at the expense of the scheduled repair hours worked through a specific number of hours worked by them, due to which a periodically repeating cycle is formed;

Each scheduled repair of electrical installations is performed 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 is based on the usual scope of work, the performance of which ensures the operational 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 inspections, which are a means of prevention.

The frequency and alternation of the planned 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 need to be replaced during repair. A special algorithm is created for performing this repair, which ensures uninterrupted operation during repair. Such an approach in preparation makes it possible to carry out a complete repair of equipment without disturbing the usual work of production.

Planned preventive well-designed repair includes:

Planning;

Preparation of electrical equipment for the planned repair;

Carrying out planned repairs;

Carrying out activities that are associated with the planned maintenance and repair.

The system of preventive maintenance of equipment includes a couple of steps:

1. Stage overhaul

It is carried out without violation of equipment operation. Includes: systematic cleaning; systematic lubrication; systematic inspection; systematic adjustment of electrical equipment; replacement of parts that have a short life; elimination of small faults.

In other words, it is prevention, which includes daily inspection and care, while it must be properly organized in order to maximize the life of the equipment, preserve quality work, and reduce the cost of scheduled repairs.

The main work performed at the turnaround stage:

Equipment status monitoring;

Conducting staff rules appropriate use;

Daily cleaning and lubrication;

Timely elimination of minor breakdowns and adjustment mechanisms.

2. Stage current

Planned preventive maintenance of electrical equipment is most often performed without disassembling the equipment, only its operation stops. It includes the elimination of breakdowns that occurred during the work. At the current stage, measurements and tests are carried out, with the help of which the defects of the equipment are detected at an early stage.

The decision on the validity of electrical equipment made repairmen. This decree is based on a comparison of the findings of tests for planned maintenance. In addition to scheduled repairs, out-of-plan work is performed to eliminate defects in equipment operation. They are carried out after exhaustion of all equipment resource.

3. Stage average

Carried out for the full or partial restoration of old equipment. It includes disassembly of components, intended for viewing, cleaning mechanisms and eliminating identified defects, replacing some quickly wearing 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 the installation of cyclical nature, volume and sequence of work in accordance with the regulatory and technical documentation. The middle stage affects the maintenance of equipment in the norm.

4. Overhaul

It is carried out by opening electrical equipment, its full inspection with inspection of all parts. Includes testing, measuring, eliminating the identified faults, as a result of which the electrical equipment is being modernized. As a result of the overhaul, the technical parameters of the devices are fully restored.

Overhaul is possible only after the overhaul stage. To conduct it, you must perform the following:

Draw up production schedules;

Conduct a preliminary inspection and verification;

Prepare documents;

Prepare tools and necessary replacement parts;

Perform fire prevention measures.

Overhaul includes:

Replacing or restoring worn mechanisms;

Modernization of any mechanisms;

Performing preventive checks and measurements;

Implementation of work related to the elimination of minor damage.

Malfunctions detected during equipment inspection are eliminated during subsequent repairs. And breakdowns that have an emergency character are eliminated immediately.

Each individual type of equipment has its own frequency of scheduled preventive maintenance, which is regulated by the Rules of technical operation. All activities are recorded in the documentation, a strict record of the availability of equipment, as well as its condition is maintained. According to the approved annual plan, a nomenclature plan is created, which reflects capital and current repairs. Before you start maintenance or overhaul, you must specify the date of installation of electrical equipment for repairs.

Schedule year of preventive maintenance  - this is the basis for drawing up a plan-estimate of the year, developed 2 times a year. The sum of the year of the plan-estimates broken down by months and quarters, it all depends on the period of the overhaul.

Today, for the system of preventive maintenance of equipment, computing and microprocessor equipment (constructions, stands, facilities for diagnostics and testing) are most often used, which affects the prevention of equipment wear, reduced repair costs, and also contributes to an increase in operating efficiency.

The distribution of staff in groups

After the choice of the form of service and the structure of the electrotechnical service of the economy, electricians and engineers and technicians are distributed among structural units.

The required number of personnel in the maintenance and repair groups or service areas is determined by the formula.

where N x - the number of personnel in the group (in the area, people);

T i - annual labor costs for the implementation of the I-th type of work in the group (on the site), people · h;

The number of personnel in the operational (duty) group is determined.

where K D - the coefficient of the participation of labor costs for operational (duty) service in the planned costs for MOT, TR, AP

(K D = 0.15 ... ..0.25).

The number of personnel in the repair group is defined as

where N rem is the number of personnel in the repair group (people);

T i - the annual labor costs for repairs, people. · H;

F D - the actual working time fund for one worker, h.

The number of staff in the maintenance team is determined by

When allocating personnel, it should be borne in mind that, according to the requirements of the safety regulations for the operation of electrical installations of consumers, at least two electricians must be assigned to each section (object), one of which is appointed as senior.

The total number of electricians in the groups (areas) of the electrical service, determined by the cost of labor (without major repairs), should not differ dramatically from the total number of electricians, determined by the average load.

Scheduling maintenance of electrical equipment

Requirements for PPR and TO schedules

The basis of the organization of work on the operation of electrical equipment are monthly, quarterly and annual maintenance and repair schedules. When developing them, the following should be considered:

Dates of electrical equipment TR should be combined with the dates of repair of machines on which it is used;

Electrical equipment used seasonally, it is advisable to repair before the period of intensive use;

The planned duration of the work must comply with the category of complexity of electrical equipment;

The time for transitions of electricians to service facilities during the working day should be reduced as much as possible;

The entire working day of electricians should be as full as possible.

The order of scheduling of PPR and TO

Scheduling is performed in the following order:

1. A working table is being developed, on the basis of which a monthly schedule of preventive maintenance is compiled. The worksheets (Appendix 1) provide a list of electrical equipment of individual production units of the farm (complex, farm, mechanical repair shops, ancillary enterprises, etc.) with an indication of the equipment installation time, the latest capital, current and emergency repairs, maintenance . Each piece of equipment is shown in a separate line.

Service planning begins with a more complex type, i.e. overhaul, then scheduled maintenance and in the last turn, set the time for MOT.

The duration of a particular outage is determined by the frequency and date of its last. If the days of repairs falls on Sunday (Saturday) or pre-holiday days, then repairs are transferred to a later or early date.

With the coincidence of the dates of the MOT, TP or CD planned for a more complex type of repair. Calendar days of capital repairs of equipment are set depending on the specific conditions of the farm or the organization involved. The timing of the next MOT and TP are determined by the frequency of their conduct. In case of violation of the periodicity of the implementation of planned preventive repairs or maintenance, their implementation is planned for the beginning of the month.

The type of repair (capital, current) or maintenance is indicated in the columns of calendar days, respectively, by the letters КР, ТР or ТО. The table also marks weekends (B) and holidays (F) days.

2. Based on the data of the worksheet, a monthly schedule of the outage is compiled (Appendix 2). Using data on the complexity of maintenance and repairs, the labor costs of electricians are determined by the day to complete the planned scope of work. Costs for CD are not taken into account if this type of repair is performed by a third-party organization.

In some cases: in case of territorial dispersion of subdivisions and small labor expenditures for performing maintenance (0.5-1 hours) and running repairs (2-8 hours); with a lack of means of transportation of workers, we can neglect the frequency of current repairs and maintenance. In this case, planning is carried out on the basis of: full shift loading of electricians (at least two people) and the minimum violation of the timing of the outage. It is not advisable to violate the frequency of the execution of the outage of electrical equipment operating in the conditions of the release of ammonia in damp rooms.

Similarly, schedules are compiled for the following months.

3. On the basis of monthly schedules are compiled quarterly and annual (Appendix 2).

When drawing up the general schedules of the outage plan for all divisions of the farm, it is necessary to ensure that there is no imposition of deadlines for carrying out work at different sites for the same services. After scheduling, they are thoroughly checked.

To ensure continuity of technological processes, MOT and TP of electrical equipment is carried out in technological breaks. The implementation of the current repair of electrical equipment is planned simultaneously with the current repair of technological equipment. Seasonal TO and TP, as well as the overhaul of electrical wiring of livestock buildings and grain grooves are planned for the period of their inactivity. These works must be completed before the start of the season of use of the production facility.

At the same time, the schedule should provide: uniform loading of electricians during the day, month and year; minimal loss of time to move and travel between objects; compliance with the normalized frequency of preventive measures (deviations should not exceed ± 35%).

The following basic principles are the basis of the CPD system:

 the implementation of preventive work must be carried out strictly according to a predetermined schedule;

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

 the volume and complexity of the preventive work performed are provided for averaged (enlarged) and are specified in each specific case depending on the technical condition of the equipment;

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

Planned preventive maintenance is a set of works aimed at maintaining and restoring the equipment. Depending on the nature and degree of wear and tear of equipment, on the volume, content and complexity of maintenance work, it includes turnaround maintenance, current, medium and major repairs.

Overhaul maintenance is preventive. It consists of regular cleaning and lubrication of equipment, inspection and testing of its mechanisms, replacement of parts with a short service life, elimination of minor malfunctions. These works, as a rule, are performed without stopping the equipment, during its current operation.

The current repair is a complex of repair work carried out between two regular capital repairs and consisting in the replacement or restoration of individual parts. Current repairs are made without complete disassembly of the equipment, but it requires a brief shutdown and removal of equipment from work with stress relief. During the current repair of equipment, external inspection, cleaning, lubrication, inspection of the mechanisms, repair of worn and worn parts, such as inspection and cleaning of the generator without rotor removal, lacquering of frontal parts, wiping insulators, inspection and cleaning of inputs at transformers and switches without changing them, are performed etc.

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

With average repairs, individual components are disassembled for inspection, cleaning of parts and elimination of detected faults, repair or replacement of wear parts or components that do not provide for normal equipment operation until the next major overhaul. Medium repairs are made at intervals no more than 1 time per year.

In the case of an overhaul, the equipment is opened and inspected with thorough internal inspection, measurements of technical parameters and elimination of detected faults. The overhaul is performed at the end of the period between turnarounds established for each type of equipment. In the event of a final repair, all worn parts are replaced or restored, the individual elements and components of the equipment are modernized. These works require disassembling of the units, complete external and internal repairs with checking the state of components and parts, a significant number of highly skilled workers, a long shutdown of electrical equipment, a large amount of testing and complex tools. The main electrical equipment is subject to major repairs in certain periods.

In contrast to the current repair, the medium and major are aimed at restoring partially or fully spent mechanical and switching equipment life.

At the end of the repair, the equipment is assembled, set up and tested. The main equipment of power plants and substations after preliminary acceptance of the repair is checked in the work under load for 24 hours.

The conclusion about the suitability of equipment for operation is made on the basis of a comparison of 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 the scheduled maintenance in the practice of power supply systems, there are unplanned repairs: emergency and unplanned. The task of the emergency repair is the elimination of the consequences of the accident or the elimination of the damage that requires the immediate shutdown of the equipment. In case of emergency (fire, isolation isolation, etc.), the equipment is stopped for repairs without the permission of the dispatcher.

Dates of capital repairs of the main equipment of power facilities are as follows:

Unscheduled repairs are agreed with the dispatcher of the system and issued the corresponding application. They are carried out to eliminate various malfunctions in the operation of equipment, as well as after triggering a switching resource by it. So, depending on the type of switches with a voltage of 6 kV and above, they are taken to unscheduled repairs after tripping 3–10 short circuits at rated tripping current.

The system of planned preventive repairs or the CPD system, as it is commonly called this method of organizing repairs, is a fairly common method that originated and became widespread in the countries of the former USSR. The peculiarity of such a “popularity” of this type of organization of repair facilities was the fact that it fairly harmoniously fit into the planned form of economic management of the time.

Now let's understand what is the outage (scheduled preventive maintenance).

The system of preventive maintenance (PPR) equipment  - a system of technical and organizational measures aimed at maintaining and (or) restoring the operational properties of process equipment and devices as a whole and (or) individual pieces of equipment, structural units and elements.

At the enterprises different types of systems of scheduled preventive repairs are used. The main similarity in their organization is that the regulation of repairs, their frequency, duration, cost of these works is of a planned nature. However, indicators for determining the timing of scheduled repairs are various indicators.

CPD classification

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

regulated outage (scheduled preventive maintenance)

• CPD by calendar period
• CPD for calendar periods with adjustments to the scope of work
• Time of work
• RCC with regulated control
• PPR on operating modes

PPR (scheduled preventive repair) as:

• PPR at permissible parameter level
• CPD at the permissible level of the parameter with the adjustment of the diagnostic plan
• CPD at the permissible level of the parameter with its prediction
• PRD with reliability control
• PRD with a predicted level of reliability

In practice, the system of regulated scheduled preventive maintenance is widespread. This can be explained by greater simplicity compared with the state-of-art PPR system. In a regulated outage, the reference goes to calendar dates and the fact that the equipment operates during the entire shift without stopping is simply accepted. In this case, the structure of the repair cycle is more symmetrical and has less phase shifts. In the case of organizing an outage system for any permissible indicator parameter, a large number of these indicators, specific to each class and type of equipment, must be taken into account.

Benefits of using an outage system or preventive maintenance of equipment

The system of scheduled preventive maintenance of equipment (CPD) 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 of the period of overhaul periods of equipment operation
• regulation of equipment downtime under repair
• forecasting the cost of repairing equipment, components and mechanisms
• analysis of the causes of equipment failure
• calculation of the number of maintenance personnel, depending on the repair complexity of equipment

Disadvantages of an outage system or scheduled preventive maintenance of equipment

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

• lack of convenient repair planning tools
• labor input calculations
• the complexity of the accounting parameter indicator
• the complexity of the operational adjustment of planned repairs

The above drawbacks of the CPD system relate to certain specifics of the technological equipment park installed in the CIS enterprises. First of all, this is a large degree of equipment wear. Often, equipment wear reaches 80–95%. This significantly distorts the system of preventive repairs, forcing specialists to correct the schedules of preventive maintenance and to carry out a large number of unplanned (emergency) repairs, which exceed the normal amount of repairs. Also, when using the method of organizing an outage system for operating time (after a certain time of equipment operation), the complexity of the system increases. In this case, it is necessary to organize the accounting of actually spent machine hours, which, together with a large fleet of equipment (hundreds and thousands of units), makes this work impracticable.

Structure of repair work in the system of equipment outage (scheduled preventive maintenance)

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

Despite the fact that the PRD system implies a trouble-free model of equipment operation and maintenance, in practice it is necessary to take into account unplanned repairs. Their cause is most often unsatisfactory technical condition or accident due to poor quality

In the organization of planning and graphing apply network scheduling.

Network planning and management includes 3 main stages:

1. A network is developed that reflects the whole complex of works, their interrelation in a certain technological sequence, which is to be accomplished in order to achieve I the set goal;

2. Optimization of the network schedule, i.e. choice of the received option;

3. Operational management and monitoring of the progress of work. The order of construction of the network schedule:

compiled a list of works;

compiled a list of events;

rational technological sequence and interrelation of works is determined;

determines the need for material and labor resources for each job;

set the duration of the work.

4.2 Drawing up a job identification card for a network schedule.

Drawing up a job identification card is the first step in network planning. The card is determined by the following data:

standards of installation time and completion date;

the project for the production of electrical work and technological maps;

current cards and prices for electrical work;

data on the duration of certain types of work on the basis of practical experience.

The Department of Chief Power Engineering works closely with the following departments:

capital construction;

chief mechanic;

marketing department;

economic planning.

Calculation of maintenance personnel

Chrem = Labor ppr / Ffak

Chrem = 1986/1435 = 1.3 = 1 man

Safety precautions take 2 people

Duty staff - around the clock

Change per day

I change - from 7-16 o'clock

II change from 16-23 hours

III shift from 23-7 hours

IV shift-exit

5. Operation of electrical equipment.

5.1 Planned preventive maintenance.

The CPD system is a set of technical and organizational measures for the maintenance, servicing and repair of equipment, carried out in a planned manner and of a precautionary nature.

Planned this system is called because all activities are carried out according to plan (schedule) in a predetermined time frame.

Preventive, it is called because in addition to repair work includes preventive measures that prevent accidents and breakdowns. These activities include:

daily care;

equipment supervision;

turnaround service - checking for accuracy;

• washing and oil change.

CPD system

Overhaul

service

Flushing