2. System of scheduled preventive maintenance of equipment
The planned preventive form of organizing the repair of technological equipment throughout the world is recognized as the most effective and has found the greatest distribution. The development of a system for scheduled preventive maintenance of equipment began in the USSR in 1923. Currently, various versions of the preventive maintenance system are the basis of the organization Maintenance and repair of equipment at enterprises in most sectors of material production and service.
System of scheduled preventive maintenance of equipment- this is a set of planned organizational and technical measures for the care, supervision of equipment, its maintenance and repair. The purpose of these measures is to prevent progressively increasing wear, prevent accidents and maintain equipment in constant readiness for work. The PPR system involves carrying out preventive measures for maintenance and scheduled repair of equipment after a certain number of hours of its operation, while the alternation and frequency of activities are determined by the characteristics of the equipment and its operating conditions.
PPR system includes
Maintenance
and scheduled equipment repairs.
Maintenance- this is a set of operations to maintain the functionality of equipment when used for its intended purpose, during storage and transportation. Maintenance includes
routine maintenance between overhauls
and periodic preventive maintenance operations.
Routine maintenance between overhauls consists of daily monitoring of the condition of the equipment and compliance with the rules of its operation, timely regulation of mechanisms and elimination of emerging minor faults. These works are performed by the main workers and repair personnel on duty (mechanics, lubricators, electricians), as a rule, without equipment downtime. Periodic preventive maintenance operations regulated and carried out by repair personnel according to a pre-developed schedule without equipment downtime. Such operations include
inspections carried out to identify defects that must be eliminated immediately or during the next scheduled repair;
flushing and oil change provided for equipment with centralized and crankcase lubrication systems;
accuracy checks performed by department staff technical control and chief mechanic.
Scheduled repairs includes
Maintenance
and major repairs.
Maintenance is carried out during the operation of the equipment in order to ensure its operability until the next scheduled repair (the next routine or major). Current repairs consist of replacing or restoring individual parts (parts, assembly units) of equipment and adjusting its mechanisms. Major renovation carried out with the aim of restoring the full or close to full resource of equipment (accuracy, power, productivity). Major repairs, as a rule, require repair work in stationary conditions and the use of special technological equipment. Therefore, it is usually necessary to remove the equipment from the foundation at the site of operation and transport it to a specialized department where major repairs are carried out. During a major overhaul, the equipment is completely disassembled, all its parts are checked, worn parts are replaced and restored, coordinates are aligned, etc.
The repair and maintenance system, depending on the nature and operating conditions of the equipment, can operate in different organizational forms:
in the form of a post-examination system,
periodic repair systems
or standard repair systems.
Post-examination system involves carrying out equipment inspections according to a pre-developed schedule, during which its condition is established and a list of defects is compiled. Based on the inspection data, the timing and content of the upcoming repairs are determined. This system is used for certain types of equipment operating under stable conditions.
Periodic repair system involves planning the timing and volume of repair work of all types based on a developed regulatory framework. The actual scope of work is adjusted relative to the standard based on the results of the inspection. This system is most common in mechanical engineering.
Standard repair system involves planning the volume and content of repair work based on precisely established standards and strict adherence to repair plans, regardless of the actual condition of the equipment. This system applies to equipment whose unscheduled shutdown is unacceptable or dangerous (for example, lifting and transport devices).
The effectiveness of the PPR system is largely determined by the development of its regulatory framework and the accuracy of the established standards. The standards of the enterprise's PPR system are differentiated by equipment groups. Basic repair standards are
repair cycles and their structure,
labor and material intensity of repair work,
material supplies for repair needs.
Repair cycle- this is the period of time from the moment the equipment is put into operation until the first overhaul or between two consecutive major overhauls. The repair cycle is the smallest repeating period of equipment operation, during which all types of maintenance and repair are carried out in the established sequence in accordance with the structure of the repair cycle. The structure of the repair cycle establishes the list, quantity and sequence of equipment repairs during the repair cycle. For example, the repair cycle structure may include the following repair sequence:
K–T 1 - T 2 - T 3 - TO,
Where T 1 , T 2 And T 3 - respectively, the first, second and third current repairs;
TO- major repairs (only one major repair is included in the repair cycle).
The content of work performed within each of the current repairs is regulated and may differ significantly from others present in the repair cycle. The structure of the repair cycle may include a small ( M) and average ( WITH) repair: for example, T 2 = C; T 1 = T 3 = M.
Similarly, the structure of the maintenance cycle can be presented, establishing the list, quantity and sequence of work on between-repair maintenance (shift inspection, partial inspection, replenishment of lubricant, replacement of lubricant, preventive adjustment, etc.). It is possible to include maintenance work ( THAT) into the structure of the repair cycle, for example:
WHO 1 - T 1 - THAT 2 - T 2 - THAT 3 - T 3 - THAT 4 - TO.
The repair cycle is measured by the operating time of the equipment; downtime during repairs is not included in the cycle. The duration of the repair cycle is determined by the service life of the main mechanisms and parts, the replacement or repair of which can be carried out during complete disassembly of the equipment. Wear of main parts depends on many factors, the main ones being
type of production, on which the intensity of equipment use depends;
physical and mechanical properties of the material being processed, on which the wear rate of equipment and its parts depends;
operating conditions, such as high humidity, dust and gas contamination;
equipment accuracy class, which determines the level of requirements for monitoring the technical condition of equipment;
Repair cycle duration T is determined in machine-hours worked by calculation using empirical dependencies that take into account the influence of many factors, including those listed above:
Where T n- standard repair cycle, hours (for example, for certain metal-cutting machines T n= 16,800 hours);
ß P , ß m , ß at , ß T , ß R- coefficients that take into account, respectively, the type of production, the type of material being processed, operating conditions, accuracy and dimensions of equipment.
The values of the coefficients and the standard duration of the repair cycle are determined on the basis of generalization and analysis of the actual data of the enterprise or are taken from reference data.
Overhaul period T mr And maintenance frequency T That are also expressed by the number of hours worked:
,
(104)
,
(105)
Where n T And n THAT- accordingly, the number of routine repairs and maintenance work per one repair cycle.
The duration of the repair cycle, the period between repairs and the frequency of maintenance can be expressed in years or months if the shift of equipment operation is known. Proper care maintenance of equipment during its operation, carrying out organizational and technical measures that extend the service life of parts and components of equipment, contribute to a change in the actual duration of the repair cycle and overhaul periods compared to the standard ones. The service life of wear parts and equipment parts is shorter than the duration of the overhaul period. Therefore, it is advisable to replace them as they wear out during the period between repairs. At the same time, the labor intensity of repairs is reduced, and the volume of work on between-repairs increases.
The labor and material intensity of repair and maintenance of equipment depends on its design features. The more complex the equipment, the larger its size and the higher the processing accuracy, the higher the complexity of its repair and maintenance, the higher the labor and material intensity of this work. Based on the complexity of the repair, the equipment is divided into categories of repair complexity. The complexity of repair work separately for the mechanical and electrical parts of the equipment is determined through the complexity of the repair complexity unit.
Repair complexity category (TO) is the degree of complexity of equipment repair. The category of repair complexity of equipment is determined by the number of units of repair complexity assigned to a given group of equipment by comparing it with the accepted standard - conditional equipment. At domestic mechanical engineering enterprises, the unit of repair complexity of a mechanical part is traditionally taken to be the repair complexity of conventional equipment, the labor intensity of a major overhaul of which is 50 hours, and the unit of repair complexity of its electrical part is 12.5 hours (1/11 of the labor intensity of a major overhaul of a 1K62 screw-cutting lathe, which is assigned the 11th category of repair complexity).
Repair unit (R. e.) is the complexity of the corresponding type of equipment repair of the first category of repair complexity. Labor intensity standards per repair unit are set by type of repair work (washing, checking, inspection, current and major repairs) separately for plumbing, machine tools and other work. The complexity of each type of repair work is determined by multiplying the time standards for this type of work for one repair unit by the number of repair units of the complexity category for repairing the corresponding equipment.
Total labor intensity of repair work (Q) in the planning period is calculated using the formula:
q K , q T And q THAT- labor intensity standards for capital and current repairs, maintenance per repair unit, hours;
n TO , n T , n THAT- number of major and current repairs, maintenance work in the planned period.
Instructions
Find information about how often the law requires preventive maintenance of the type of equipment your organization uses. For this purpose, there are special collections of standards for types of equipment. They can be purchased in bookstores in the departments technical literature or borrow it from the library. But at the same time, in view of the fact that they must be relevant, so choose the newest collection from those offered.
Start filling out the created table. In the first column, write down the equipment, modification and manufacturer. Next, indicate the inventory number given to this equipment at your enterprise. In columns three to five, information is entered about how long this or that can work technical device between scheduled repairs. Take this information from the code reference book.
From the sixth to the tenth paragraph, information is provided about when the last equipment repairs were carried out. Both scheduled checks and various unexpected problems are indicated.
Further, points from eleven to twenty-two are designated by the months of the coming year. In each of them you must check whether planned or major repairs of a particular one are planned during this period. Before doing this, review the standards for equipment repair and draw a conclusion about when it is best to carry out a technical inspection of a particular machine.
In the twenty-third column you need the annual period of stay of the machine in. To do this, add up all the days that rely on the repair of this type of equipment according to the regulations, and indicate the resulting figure in the table.
In the last, twenty-fourth paragraph, indicate total time, which the machine must operate for a year. To do this, add up all the hours during which the device will be used in a year, and subtract from them the time allotted for repairs.
Sources:
- how to make a ppr
The work of an editorial office is a complex mechanism in which everything must function without interruption. One small mistake or delay - and the issue of a newspaper or magazine may not be published on time. To avoid various unpleasant and unforeseen situations, an editorial schedule or plan is needed. There are different schedules - for one issue, for a week, for a quarter, for a month, for a year.
Instructions
Let's say you need to draw up an editorial plan for the delivery of the next issue of a magazine. Let's say you are the managing editor of a specialized monthly magazine for owners retail outlets. You have one month left for pre-press preparation of the publication. First of all, you need to identify the topic of the issue. For example, it would be relevant now to talk with entrepreneurs about the features of summer trading.
Then decide by what date each material should be prepared. This can also be noted in the created table. Do not forget that preparing materials will require journalists time to collect invoices, conduct interviews, and write texts. And in order for the magazine to reach the printing shop on time, it will also take time for the work of other, no less important, editorial staff. Keep these points in mind when creating your schedule.
Also in editorial terms, it is necessary to note the deadlines, proofreaders and other specialists working on the creation of the issue. For convenience, you can make another table. In it, indicate the deadlines that will be required for the texts to be proofread by the editor,
PZ No. 4. Calculation of equipment maintenance schedule.
Task No. 1. The operating time of the pump between major repairs is 8640 hours, medium - 2160 hours, current - 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 a mileage after major repairs of 7320 hours, average - 840 hours, current - 120 hours. Draw up a pump maintenance schedule for a year.
Solution.
To draw up a pump maintenance schedule 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, take February.
Current (2160 – 840) / 3 * 8 * 30 = 1.8 months, take February
RTO (720 – 120) / 3 * 8 * 30 = 0.8 months, we take January.
3. Determine how many months later it is necessary to carry out subsequent repairs:
Capital 8640 / 3 * 8 * 30 = 12 months, we take 12 months, i.e. next year;
Current 2160 / 720 = 3 months, we accept after 3 months, those in February, May, August, November.
RTO 720 / 720 = 1 month, accepted after 1 month, i.e. every month except February, May, August and November.
4. We draw up a PPR schedule for the pump:
Month: Jan. Feb. Mar Apr May June July Aug Sep. Oct. Nov. Dec
View TO TO TO TO TO TO TO TO TO TO
repairs
Task 2. There are 20 dryers in the polyvinyl chloride resin production workshop. The actual operating time of one dryer per year is 6480 hours, the duration of the cycle between repairs is 8640 hours, from major to current repairs is 4320 hours, between repairs and maintenance is 864 hours. The calendar operating time of the equipment per year is 8640 hours. Determine number of overhauls, routine 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 repair = Ood.ob. * Tfact * n in. repair / Shopping center, where
Ood.ob. – the number of units of the same type of equipment in operation;
Tts – duration of the overhaul cycle, hour;
Tfact – 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 / Tts
current
n avg. = Tk / Tts.t. - 1
repair and maintenance services
n pto = Tc / Tc.t. - ∑ (drip + current), where
Тк – calendar operating time of the equipment, hour.
Tts.t. – duration of the overhaul period from major to current repairs, hour;
∑ (overhaul + current..) – the sum of capital and current repairs.
Task 3. Calculate the number of compressor repairs based on the following data: number of compressors - 8, duration of the cycle between repairs = 8640 hours, period between overhauls - 7130 hours, between current ones - 2160 hours, between technical repairs - 720 hours. Actual number of days of work per year – 358, number of shifts – 3, shift duration – 8 hours.
Methodical instructions.
To complete the task, use the calculation formulas given in methodological guidelines to task 2.
Task 4. Draw up a equipment maintenance schedule based on the data given below:
|
Indicators |
Option 1 |
Option 2 |
Option 3 |
|
Equipment |
Compressor |
Dryer |
Autoclave |
|
Operating time between repairs, hours |
|||
|
Capital |
7130 |
14700 |
8238 |
|
Current |
2160 |
2880 |
2880 |
|
RTO |
|||
|
Actual number of working days per year |
|||
|
Number of shifts |
|||
|
Cont. working day, hour |
|||
|
Cont. mileage after repair by the beginning of the year, h. |
|||
|
Capital |
5310 |
12200 |
7310 |
|
Current |
1950 |
||
|
RTO |
Methodical instructions.
To complete the task, use the calculation formulas given in the guidelines for task 1.
Task 5. Determine the equipment downtime for repairs using the data below:
|
Indicators |
Pump |
Distillation column |
Bake |
|
Labor intensity of repairs, person-hours |
|||
|
number |
|||
|
riggers |
|||
|
locksmiths |
|||
|
welders |
|||
|
Working hours |
|||
|
Number of shifts |
Guidelines
Downtime is equal to the quotient of the division: the numerator is the labor intensity of the repair, the denominator is the product of the number of repairmen by the length of the working day and the rate of completion of the norm.
5. FORMS OF REPAIR DOCUMENTATION
5.1. The repair documentation of this Handbook is maximally unified with the documentation of industry “Maintenance and Repair Systems” energy equipment" Provides for maintaining following forms repair documentation (forms 1-19):
a shift log of identified defects and work to eliminate them; repair log; list of defects; cost estimate;
certificate of delivery for major repairs;
certificate of release from major repairs;
annual preventive maintenance schedule;
monthly plan-schedule-report of PPR or monthly repair report;
statement of annual repair costs;
act for changing the calendar period of repairs;
shutdown schedule;
log of installation and removal of plugs;
act of acceptance of work after shutdown repairs;
passport of power equipment;
nomenclature of the main equipment of the workshop;
range of auxiliary equipment;
work permit for repair work;
permission to carry out excavation work on the territory.
5.2. Changes and additions to previously existing forms of repair documentation were made based on the results of testing the “Unified Regulations on Scheduled Preventive Maintenance of Equipment” industrial enterprises Russia" (Order of the Ministry of Industry and Science of Russia dated May 29, 2003 05.900 114–108).
5.3. The main document by which equipment repairs are carried out is the annual repair schedule (Form 7), on the basis of which the need for repair personnel, materials, spare parts, and purchased components is determined. It includes each unit of equipment subject to major repairs. The basis for drawing up the annual schedule is the standards for the frequency of equipment repairs given in this Handbook.
5.4. In order to link the timing of repairs of power equipment with technological equipment the annual schedule is agreed upon with the enterprise's management department. If it is necessary to use the services of the chief instrument technician, the planned repair periods are agreed upon with the OCP. The timing of repairs of capital equipment that limits the implementation of the production program is agreed with planning department enterprises.
5.5. In columns 11–22 of the annual schedule (Form 7), each of which corresponds to one month, the symbol in the form of a fraction indicates: in the numerator - the planned type of repair (K - capital, T - current), in the denominator - the duration of downtime in hours. Notes on the actual completion of repairs in these columns are made by coloring the planned numbers with a colored pencil.
In columns 23 and 24, respectively, the annual equipment downtime for repairs and the annual working time fund are recorded.
5.6. The operational document for equipment repair is a monthly plan-schedule-report, approved by the chief power engineer of the enterprise for each energy department and section (Form 8). It is allowed to maintain a monthly repair report (Form 8A) instead of a monthly plan-schedule-report.
5.7. In this case, monthly repair planning is carried out in accordance with the annual repair schedule.
5.8. In columns 7-37 (Form 8), each of which corresponds to one day of the month, the symbol in the form of a fraction indicates: in the numerator - the type of repair (K - capital, T - current), in the denominator - its duration (current - in hours , capital – in days).
5.9. A note on the actual completion of repairs is made after their completion by a specially appointed responsible person in the OGE, in production workshops - as a workshop foreman.
5.10. The logbook for the installation and removal of plugs (Form 14) is kept by the deputy head of the energy department (head of department, installation, shift supervisor).
5.11. Explanations on the procedure for maintaining other repair documentation are given above in the relevant sections.
5.12. The repair documentation forms given in this section are typical. Depending on the specifics of accounting for ongoing repair and maintenance activities that are not regulated by this Handbook (repair inspections, checks, tests, etc.) in the repair services of enterprises, additional columns (items) may be included in the repair documentation forms.
Form 1
Form 2
Form 3
Form 4
Form 5
Form 6
Form 7
Form 8
Form 8A
Form 9
Form 10
Form 11
Form 12
Form 13
Form 14
Main stages of PPR equipment
Planned and preventative well-designed repairs include:
Planning;
Preparation of electrical equipment for scheduled repairs;
Carrying out scheduled repairs;
Carrying out activities related to scheduled maintenance and repairs.
The system of scheduled preventive maintenance of equipment includes a couple of stages:
1. Inter-repair phase
Performed without disturbing the operation of the equipment. Includes: systematic cleaning; systematic lubrication; systematic examination; systematic adjustment of electrical equipment; replacement of parts that have a short service life; elimination of minor faults.
In other words, this is prevention, which includes daily inspection and care, and it must be properly organized in order to maximize the service life of the equipment, maintain high-quality work, and reduce the cost of scheduled repairs.
The main work performed during the overhaul phase:
Monitoring the condition of equipment;
Enforcement of appropriate use policies by employees;
Daily cleaning and lubrication;
Timely elimination of minor breakdowns and adjustment of mechanisms.
2. Current stage
Planned preventative maintenance of electrical equipment is most often carried out without disassembling the equipment, only stopping its operation. Includes the elimination of breakdowns that occurred during operation. At the current stage, measurements and tests are carried out, with the help of which equipment defects are identified at an early stage.
The decision on the suitability of electrical equipment is made by repairmen. This ruling is based on a comparison of test findings during routine maintenance. In addition to scheduled repairs, unplanned work is performed to eliminate defects in equipment operation. They are carried out after the entire resource of the equipment has been exhausted.
3. Middle stage
Carried out for the complete or partial restoration of used equipment. 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 scheduled preventive maintenance of equipment includes setting the cyclicity, volume and sequence of work in accordance with the regulatory and technical documentation. Middle stage affects the maintenance of equipment in good condition.
4. Major renovation
It is carried out by opening electrical equipment, checking it completely and inspecting all parts. Includes testing, measurements, elimination of identified faults, as a result of which electrical equipment is modernized. As a result of major repairs, full recovery technical parameters devices.
Major repairs are possible only after the inter-repair phase. To carry it out you must do the following:
Draw up work schedules;
Conduct preliminary inspection and verification;
Prepare documents;
Prepare tools and necessary replacement parts;
Carry out fire prevention measures.
Major repairs include:
Replacement or restoration of worn mechanisms;
Modernization of any mechanisms;
Carrying out preventative checks and measurements;
Carrying out work related to the elimination of minor damage.
Malfunctions discovered during equipment testing are eliminated during subsequent repairs. And breakdowns of an emergency nature are eliminated immediately.
PPR systems and its basic concepts
The system for scheduled preventive maintenance of power equipment (hereinafter referred to as the SystemPPREO) is a complex methodological recommendations, norms and regulations designed to ensure effective organization, planning and carrying out maintenance (TO) and repair of power equipment. The recommendations given in this PPR EO System can be used at enterprises of any type of activity and form of ownership that use similar equipment, taking into account specific conditions their work.
The planned and preventive nature of the EO PPR System is implemented by: carrying out equipment repairs at a given frequency, the timing and logistics of which are planned in advance; carrying out maintenance operations and technical condition monitoring aimed at preventing equipment failures and maintaining its serviceability and performance in the intervals between repairs.
The EO PPR system was created taking into account new economic and legal conditions, and in technical terms, with maximum use of: the capabilities and advantages of the aggregate repair method; the entire range of strategies, forms and methods of maintenance and repair, including new means and methods technical diagnostics; modern computer technology And computer technology collecting, accumulating and processing information about the condition of equipment, planning repair and preventive actions and their logistics.
The operation of the PPR EO System applies to all equipment of energy and technological workshops of enterprises, regardless of the place of its use.
All equipment operated at enterprises is divided into basic and non-core. The main equipment is the equipment with the direct participation of which the main energy and technological processes of obtaining a product (final or intermediate) are carried out, and the failure of which leads to a cessation or a sharp reduction in the output of products (energy). Non-core equipment ensures the full flow of energy and technological processes and the operation of the main equipment.
Depending on the production significance and functions performed in the energy and technological processes equipment of the same type and name can be classified as both primary and non-main.
The EO PPR system provides that the equipment’s need for repair and preventive actions is satisfied by a combination various types Maintenance and scheduled repairs of equipment, differing in frequency and scope of work. Depending on the production significance of the equipment, the impact of its failures on personnel safety and the stability of energy technological processes, repair actions are implemented in the form of regulated repairs, repairs based on operating hours, repairs based on technical condition, or a combination of them.
Table 5 - number of repairs in 12 months
Table 6 - Planned balance of working time for the year
Payroll ratio
- 1. For discontinuous production =1.8
- 2. For continuous production =1.6
