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Methodology for improving the efficiency of maintenance workshops. Maintenance strategies and ways to improve the efficiency of repair work. Depending on the market

02.09.2020
Methodology for improving the efficiency of maintenance workshops. Maintenance strategies and ways to improve the efficiency of repair work. Depending on the market

Reliable and safe operation of systems, equipment, buildings and structures of enterprises is inextricably linked with repair activities. EZh spoke about the directions for improving the management structure of the maintenance and repair system last year (see No. 32). Today we will talk about approaches to assessing the effectiveness of maintenance and repair work. Vladimir Minaev says CEO OJSC Atomenergoremont, Ph.D.

The maintenance and repair system is a set of processes, organizational structures, means of technical equipment of repair, methodological support providing efficient maintenance and repair of enterprise equipment.

Repair Strategies

Here are three main strategies.

The first is the classic scheduled preventive maintenance (PPR). It involves a repair cycle (a predetermined sequence of repairs of a certain type and intervals between them) and a task of the scope of work when performing repairs of a certain type. In the PPR variant, called "planning by operating time", with given volumes and maintaining a fixed sequence of repairs, the time between them is determined not on a calendar basis, but depending on the operating time of the equipment (hours of operation, number of starts, etc.).

The second is failure repair. The equipment is repaired (or replaced) due to its failure and the inability to further use. Technically, this is justified for some types of equipment if its elements fail accidentally, regardless of the duration of their operation; economically, when the consequences of a breakdown are insignificant, and preventive measures are more expensive than replacing a failed unit or device. If there is clear evidence of an impending failure (increased vibration, oil leakage, temperature rise above the acceptable level, signs of unacceptable wear), you can choose the “repair as defects” option.

The third is “repair according to condition”. With this strategy, the volume of repairs and the time between them are not fixed in advance, but are determined by the results of regular revisions (examinations) of equipment and monitoring of its condition using automated control and diagnostic tools. This strategy can significantly save resources, so it is considered the most progressive for complex and expensive equipment.

For the customer, the method of aggregate repair, which involves the replacement of the unit either in its entirety or part of it, and after-sales service of the equipment, is becoming more profitable and a priority today. This method significantly reduces repair time. In many industries, after-sales service is common and, although it costs the customer a little more, it has a great chance for the future.

Our maintenance and repair system is mainly based on carrying out maintenance work. In the near future, it is planned to switch to the repair of a number of equipment according to its technical condition and the use of the method of aggregate repair and maintenance of equipment.

MRO efficiency

The efficiency of maintenance and repair is determined by the ratio of the maximum possible result of maintenance and repair ( high quality of works while observing the standard repair period) to the minimum possible operating costs (the minimum reasonable level of costs without loss of quality and volume of work performed).

The result of maintenance and repair works, as well as reconstruction and modernization of equipment of power units, plant-wide systems, external facilities of operating NPPs, is their reliable and trouble-free operation in the planned overhaul period. Economically, this means no financial losses for under-produced electricity due to unscheduled shutdowns and downtime of NPP equipment for repairs.

The performance of the repair personnel, as a rule, is estimated by the average monthly output per worker (see diagram).

Such a measurement of labor productivity has a significant drawback - it depends on the limited funds for repairs, the price structure, the number of staff and the billing of work. And when manipulating coefficients to estimates, directive cost reduction in terms of maintenance and repair limits, the existing regulated duration of repairs, this approach does not reflect the actual labor productivity - the price component is too high.

It is more correct to use resource assessment methods 1 .

Here are three such indicators.

The complexity of repair is the main resource indicator. Labor intensity is regulated quantitatively by technical regulation 2 .

For example, the labor intensity of an average repair of a serial block of a nuclear power plant is 520,000 man-hours, the duration of repairs in one case is 40 days, in the other - 35 (13,000 man-hours / day and 15,000 man-hours / day, respectively). Obviously, in the second case, the productivity of the repair personnel is higher.

The standard number of personnel for repairs is another important indicator of labor productivity (the ratio of the standard number of employees calculated according to the regulatory framework to those actually employed in repairs).

The third indicator is the labor productivity index. It can be represented on the basis of actual and natural resource data in the form of dependencies:

IPT \u003d TrE / DlR;

IPT \u003d LF / HF,

where: IPT - labor productivity index;

TrE is the complexity of the block repair;

DlR - the duration of the block repair (can be standard and actual);

LF is the standard number of personnel required to perform unit repairs;

FC - the actual number of personnel involved in the repair of the unit.

According to the methodology approved by the concern 3, one of the indicators is the reduction of the repair period 4:

  • at the stage of forming the repair schedule for the planned year - an assessment of the predicted financial result from reducing the repair time compared to the normative ones to determine the feasibility of making a decision to reduce the repair time;
  • based on the results of the completion of repairs - an assessment of the actual financial result from the reduction of the repair period in order to confirm the correctness of the decisions made during planning.

The results of assessing the effectiveness of reducing the repair time are used to motivate the work of NPP repair personnel and contractors.

And since the duration of the repair cannot be reduced to the detriment of the reliable and safe operation NPP, the methodology provides the main directions for reducing the time:

  • intensification of work of repair personnel;
  • development of a high production culture with elements of lean production (Rosatom production system);
  • introduction of the latest technologies in repair;
  • use of modern means of technological equipment and highly efficient equipment for repairs.

At the same time, the reduction in repair time is associated with additional income in the form of proceeds from the sale of additionally generated electrical energy(provided that it is in demand in the market) and the costs due to the intensification (transition to three-shift work) of the work of maintenance personnel.

Reducing the repair time is economically efficient, provided that the additional costs are covered by the proceeds from the sale of additional generated electricity and at the same time there is additional profit.

Ways to improve the efficiency of maintenance and repair

Increasing the efficiency of maintenance and repair is the process of reducing losses from underproduction of electricity due to shutdowns and downtime of NPP systems and equipment in repair while optimizing the costs of maintenance and repair without losing the quality of work performed.

IN nuclear power the ability to manage production, make timely decisions is especially important because of possible consequences with the inaction of leaders. A branched structure with many levels of management can lead to confusion in production, acceptance wrong decisions or, even worse, not accepting them at all. Eliminating the consequences of such management is very expensive.

Here are the main ways to improve the efficiency of maintenance and repair and directions for their implementation.

1. Improving the management structure of the maintenance and repair system (see "Ezh", 2012, No. 32).

2. Optimization of scheduled PPR deadlines.

2.1. Implementation of a unified industry system economic planning resources.

Given the extensive branch network, the use of a unified approach to resource planning is a priority for the company. And the desired result can be achieved only with a rigid economically justified centralization of resources.

2.2. Introduction of new technologies for the repair of equipment and means of technological equipment for maintenance and repair.

As part of the technical re-equipment, an investment program has been developed, including:

  • development and mastering of new technologies;
  • equipping with modern technological means of repair;
  • construction and equipment of production bases;
  • training and retraining of repair personnel.

2.3. Perfection technical documentation to processes.

Since the technological documentation for maintenance and repair was prepared many years ago and is based on the technologies of the last century, its quality needs to be improved:

  • constant updating in connection with changing regulatory documents;
  • finalization due to the need to apply technologies on the same type of equipment of different NPPs of the same project in order to unify processes.

Documentation, especially good documentation, has long been a commodity, and its distribution is limited. Like experience, it is the legacy of the current generation, so its relevance and improvement will affect the quality and reliability of the work of those who come to replace us.

2.4 Improving the quality of training of maintenance personnel in specialized training centers using full-scale mock-ups and full-scale equipment samples (the Engineering and Technical Center of the company conducts training, retraining and maintaining the qualifications of workers in more than 100 training programs in 37 specialties).

3. Reducing losses from underproduction of electricity as a result of unscheduled shutdowns and equipment downtime for repairs.

3.1 Improvement of the maintenance and repair management system by switching to management of maintenance and repair as a project:

  • an integrated approach to resource planning (taking into account the availability of material and human resources);
  • scheduling of work
  • MRO (typical - based on a comprehensive analysis of their performance in previous periods and at other facilities. Preparation for the performance of non-standard special works should be started at least a year before the start of their implementation);
  • resource dispatching for maintenance and repair (management of material and human resources should be carried out under the conditions of a single procurement standard).

3.2 Creation of a repair management subsystem based on ACS-Remont, integrated into a single industry information system:

  • creation of a unified database of equipment;
  • creation of a unified maintenance and repair resource management system;
  • maintenance and repair logistics management (creation regulatory framework inventories);
  • optimization of PPR planning (reduction of PPR terms at those sites where it is relevant and economically feasible).

3.3 Creation of a workable quality assurance system during maintenance and repair includes the development of:

  • sectoral guidance on establishing a quality system (guidance should cover activities at all stages of the life cycle from the design stage to decommissioning);
  • quality assurance systems at NPPs of the concern, taking into account the improvement of the system for developing and monitoring the implementation of corrective actions, and not corrections, for violations in work related to equipment repair;
  • a quality management program for maintenance and repair that meets current industry trends, takes into account the features of the equipment of units in operation and under construction, and also describes effective measures and methods for quality management, and not just its control.

4. Reducing operating costs in terms of total maintenance and repair costs.

4.1. Optimization of repair work volumes:

  • development and approval of new regulatory documents for the implementation of maintenance and repair with supervisory authorities and manufacturers;
  • justification for the transition from a four-year to an eight-year repair cycle of metal control;
  • introduction of a comprehensive diagnostics of the technical condition of equipment (very little attention has been paid to this area of ​​activity so far, even new equipment for units under construction is not sufficiently equipped with these devices).

4.2. Optimization of the distribution of work performed by the economic and contracting method.

Proposals for optimizing maintenance and repair costs, taking into account the specifics of the financial and economic activities of the company, are given in the table.

The transition to new equipment repair technologies, primarily to repair according to technical condition, will significantly increase the efficiency of maintenance and repair.

The principle of organization of repair according to technical condition can be implemented in the organization of service maintenance of equipment with the solution of the following issues:

  • who, in what ways, with the help of what criteria (technical, economic) will determine the technical condition of the equipment and the feasibility of its repair or replacement;
  • responsibility for decisions made and their consequences;
  • communication with the authors of the project, equipment manufacturers and registration of the necessary approvals with design, engineering and supervisory organizations and authorities;
  • collection of statistical data, their systematization and analysis, evaluation residual resource equipment, its elements and development of recommendations on necessary measures;
  • development of new regulations and normative and technical documents on repair technology;
  • tracking world achievements in repair technology and technical equipment, adapting them to the real conditions of Russian nuclear power plants, implementation and scientific and technical support;
  • development and implementation of new diagnostic systems for the technical condition of equipment;
  • examination of projects for the construction of new NPPs and development of proposals in terms of repair services;
  • training and retraining of repair personnel.

Within the framework of the investment program - organization of the NPP MRO production process - it is planned to carry out measures to organize the repair of equipment according to the technical condition:

  • preparation of "medical records" of equipment repaired according to technical
  • condition (together with NPP);
  • monitoring the availability of equipment diagnostic tools (not provided in the factory supply) and selection of a supplier (together with the NPP);
  • development of programs and methods for diagnosing equipment (with the determination of controlled parameters) being repaired according to its technical condition;
  • training of personnel to work on modern equipment and diagnostic devices.

All ways to improve the efficiency of maintenance and repair work are associated with costs to varying degrees, and it is the customer's prerogative to decide which of them to use. Only an integrated approach in choosing ways to improve the efficiency of maintenance and repair works leads to the best result.

1 The resource approach to assessing labor productivity and production efficiency is traditionally used to a greater extent in the production of goods, rather than in the provision of services.

2 Technical regulation - the establishment of technically sound standards for labor costs, machine time and material resources per unit of production.

3 Methodology for assessing the effectiveness of the work of repair personnel in optimizing the terms of repair of NPP power units.

4 According to the methodology, the reduction of the NPP unit repair time cannot be done to the detriment of the reliable and safe operation of the NPP.

Measures to optimize maintenance and repair costs

Cost level

Events

Peculiarities

Expenses
concern

1. Optimization of the number of personnel involved in the performance of maintenance and repair work - substantiation of the optimal ratio of the concern's costs for maintenance and repair, performed by economic and contract methods.

2. Establishment of the criteria used in the process of budgeting the company as a service company of the concern

1. The need to bring the expenditure items of the concern's budget into line with the revenue items of the company's budget.

2. The need to take into account the possibility of increasing the costs of society when performing maintenance and repair in a contract way

Expenses
societies

1. Optimization of the number of the company's personnel - optimization of the ratio of own costs to the costs of attracting subcontractors.

2. Building financial and economic relations with the concern in order to prevent cash gaps and ensure financial stability society. Reduction of receivables.

3. Implementation of the financial policy of the company in the field of compliance with the expenditure and revenue parts of its budget. Improving budget planning processes.

4. Development and implementation of a cost reduction program.

5. Implementation of financial policy in financial relations between the central office and branches of the company. Refinement of the company's ORD in terms of ensuring the financial discipline of branches. Improving internal cash flow management processes.

6. Improving accounts payable management processes

1. The requirement to unconditionally meet the needs of customers in high-quality comprehensive services for maintenance and repair, reconstruction and modernization of systems and equipment, buildings and structures of nuclear facilities. Since when performing work “at the peak of repairs”, the company must have a sufficient number of repair personnel with the necessary qualifications, its costs are less tied to revenue (production volumes) than in classical production enterprises.

2. An increase in the share of own costs leads to an increase in the productivity of employees and, consequently, an improvement in financial condition society.

3. An increase in the share of own costs should be accompanied by an increase in wages and social guarantees employees.

4. Increasing the share of own costs in excess of the optimal one will not allow realizing the advantages of the economic method of performing maintenance and repair in comparison with the contract method

STO 70238424.27.100.012-2008

STANDARD OF ORGANIZATION NP "INVEL"

HEAT AND HYDRAULIC PLANTS

Methods for assessing the quality of repair of power equipment

OKS 03.080.10
03.120

Introduction date 2008-10-31

Foreword

The basics for ensuring the safe operation and repair of hazardous production facilities, including power plant equipment, the goals and principles of standardization of the relevant norms and requirements are established by the Federal Laws of July 21, 1997 N 116-FZ "On Industrial Safety of Hazardous Production Facilities" and of December 27, 2002 N 184-FZ "On Technical Regulation" .

This fundamental standard of the NP "INVEL" organization establishes general requirements for assessing the quality of repair of the main and auxiliary equipment of thermal and hydraulic power plants. Specific requirements for the quality of repair of each type (type) of equipment are established by separate standards of the organization " Specifications for equipment overhaul. Norms and requirements", the fulfillment of the requirements of which determines the quality of the repair.

The application of this standard, together with other standards of NP "INVEL", will ensure the fulfillment of the mandatory requirements established in the technical regulations for the safety of technical systems, installations and equipment of power plants.

About the standard

1. DEVELOPED by Open Joint Stock Company "Central Design Bureau Energoremont" (JSC "TsKB Energoremont")

2. INTRODUCED by the Central Commission of OAO RAO "UES of Russia" for technical regulation

3. APPROVED AND PUT INTO EFFECT by the Order of NP "INVEL" dated 01.07.2008 N 12/9

4. INSTEAD OF STO w/n (Order of JSC RAO "UES of Russia" dated April 23, 2007 N 275)

1 area of ​​use

1 area of ​​use

This foundational organization standard:

- is a regulatory document that establishes technical and organizational requirements for assessing the quality of repair and repaired equipment of power plants, aimed at ensuring industrial safety, environmental safety, increasing reliability and efficiency of operation, as well as determining the methodology to be applied in this assessment;

- establishes the basic provisions, procedure, norms and methods for assessing the quality of repair of the main and auxiliary equipment of thermal and hydraulic power plants;

- is intended for use by wholesale, territorial and regional generating companies, operating organizations at thermal and hydraulic power plants, repair and other organizations that carry out repair maintenance of power plant equipment.

2 Normative references

This standard uses normative references to the following standards:

Federal Law "On Technical Regulation" dated December 27, 2002 N 184-FZ

GOST R 1.4-2004 Standardization in the Russian Federation. Organization standards. General provisions

GOST R 1.5-2004 Standardization in the Russian Federation. National standards of the Russian Federation. Rules for construction, presentation, design and designation

GOST 1.5-2001 Interstate standardization system. Interstate standards, rules and recommendations on the interstate standardization system. General requirements to the construction, presentation, design, content and designation

GOST 2.102-68 one system design documentation. Types and completeness of design documents

GOST 2.601-95 * Unified system for design documentation. Operating documents
________________
* The document is not valid on the territory of the Russian Federation. GOST 2.601-2006 is in force, hereinafter in the text. - Database manufacturer's note.

GOST 2.602-95 Unified system for design documentation. Repair documents

STO 70238424.27.010.001-2008 Power industry. Terms and Definitions

STO 70238424.27.140.001-2008* Hydroelectric power plants. Methods for assessing the technical condition of the main equipment.
________________
* The document is not valid. STO 70238424.27.140.001-2011 is valid, hereinafter in the text. - Database manufacturer's note
.

3 Terms, definitions, symbols and abbreviations

3.1 Terms and definitions

This standard uses terms and definitions in accordance with STO 70238424.27.010.001-2008, as well as the following terms with the corresponding definitions:

3.1.1 characteristic: distinctive property. In this context, characteristics are physical (mechanical, electrical, chemical) and functional (performance, power...);

3.1.2 quality characteristic: An inherent characteristic of a product, process or system resulting from requirements;

3.1.3 normative and technical documentation; NTD: Documents establishing requirements;

3.1.4 quality of repaired equipment: The degree of compliance of the totality of the quality characteristics inherent in the equipment, obtained as a result of its repair, with the requirements established in the regulatory and technical documentation;

3.1.5 equipment repair quality: The degree of fulfillment of the requirements established in the regulatory and technical documentation, when implementing a set of operations to restore the serviceability or operability of the equipment and restore the resource of the equipment or its components;

3.1.6 assessment of the quality of equipment repair: Establishing the degree of compliance of the results obtained during the survey, fault detection, control and testing after the elimination of defects, the quality characteristics of the equipment established in the regulatory and technical documentation;

3.1.7 methodology for assessing the quality of equipment repair: A document that establishes requirements for the use of a set of methods for survey, fault detection, control, testing of equipment and for determining characteristics;

3.1.8 specifications for overhaul: A regulatory document containing requirements for fault detection of a product and its components, repair methods to eliminate defects, technical requirements, values ​​of indicators and quality standards that the product must satisfy after overhaul, requirements for control and testing during repair and after repair.

3.2 Symbols and abbreviations

The following symbols and abbreviations are used in this standard:

Normative and technical documents;

PTE

Rules for technical operation;

Specifications;

operating organization.

4 Fundamentals

4.1 The Federal Law "On Technical Regulation" defines the safety of products, processes of production, operation, storage, transportation, sale and disposal as a state in which there is no unacceptable risk associated with causing harm to the life or health of citizens, property of individuals or legal entities, state or municipal property, the environment, the life or health of animals and plants.

In accordance with the Federal Law of July 21, 1997 N 116-FZ "On Industrial Safety of Hazardous Production Facilities", individual workshops, sections and production sites of power plants are identified as hazardous production facilities that pose a threat to the health and life of plant personnel, the public and the environment. The Law includes the maintenance and repair of equipment and technical devices used at hazardous production facilities, identified in the industrial safety in due course within power plants.

4.2 During the operation of power plant equipment, its technical condition changes, which determines the decrease in reliability, efficiency of use and the likelihood of deterioration in industrial, environmental and other types of safety. Restoration of equipment quality is carried out within the framework of the system of maintenance and repair of power plant equipment.

The main goal of the functioning of the system operating at power plants Maintenance and repair of power plant equipment is to perform maintenance and repair and ensure the required level of quality of the repaired equipment to ensure the safe operation of the power plant, the reliability of the repaired equipment, maintaining stable performance characteristics equipment and its efficiency during the service life within the limits of safety, reliability and efficiency established by regulatory and technical documentation.

4.3 Monitoring and assessing the quality of repairs are prerequisite ensuring the required level of quality of the repaired equipment of power plants.

Assessment of the quality of repair of power plant equipment is carried out:

- in terms of the quality of the repaired equipment;

- according to the degree of compliance with the requirements of regulatory and technical documentation for repairs to components, assemblies, parts and equipment as a whole during the repair process, which determines the quality of the repaired equipment.

4.4 This standard has developed a methodology for assessing the quality of repairs for various kinds power plant equipment, which is based on a unified methodology, according to which the methodology for assessing the quality of repair of a particular type (type) of power plant equipment includes two components:



- methods for assessing compliance with the requirements of regulatory and technical documentation for repairs to components, assemblies, parts and equipment as a whole during the repair process to restore the physical and functional properties of the equipment.

4.5 The main regulatory documents that establish the quality indicators of repaired equipment and the requirements of regulatory and technical documentation for repairs to components, assemblies, parts and equipment as a whole in the course of repair are the standards of the organization of the group "Technical conditions for major repairs. Norms and requirements" (hereinafter referred to as technical specifications for major repairs), corresponding to the type and type of equipment of the power plant.

4.6 When accepting equipment from repair, an assessment of the quality of the repair should be carried out, containing:

- assessment of the quality of repaired equipment;

- assessment of the quality of the repair work performed.

When determining these estimates, the results of meeting the requirements of the technical conditions for the repair of equipment should be taken into account.

5 General requirements for assessing the quality of repairs

5.1 Evaluation of the quality of repaired equipment

5.1.1 The assessment of the quality of the repaired equipment characterizes the technical condition of the equipment after repair and its compliance with the requirements of regulatory and technical documentation.

The regulatory and technical documentation, in accordance with which the quality of repairs is assessed, includes: Rules for the technical operation of power plants and networks of the Russian Federation, standards "Technical conditions for overhaul", regulatory and design documentation equipment manufacturers.

Repaired equipment can be assigned one of the following quality ratings:

- meets the requirements of NTD;

- meets the requirements of NTD with restriction;

- does not meet the requirements of the NTD.

5.1.2 The rating "complies with the requirements of the NTD" is set if all the defects identified as a result of the control of the components of the equipment have been eliminated; the requirements of the NTD, which determine the quality of the equipment, are met; acceptance tests have shown that the start-up, loading and operation of equipment in different modes comply with the requirements of standards (instructions) for operation; the values ​​of the quality indicators of the repaired equipment are at the standard level.

5.1.3 The rating "complies with the requirements of the NTD with a restriction" is set if:

- part of the requirements of the NTD for the repaired equipment has not been met;

- individual defects with which the equipment can temporarily work have not been eliminated;

- there are comments on the operation of the equipment in various modes;

- the values ​​of individual quality indicators do not correspond to the standard level, but further operation in accordance with the requirements of the NTD is possible, and the acceptance committee decides on the temporary operation of the equipment.

5.1.4 Equipment repaired with an assessment of "complies with the requirements of the NTD with a limitation" is allowed for operation with a limited period of further use, while an action plan should be developed to eliminate the identified deficiencies and the deadlines for its implementation should be established.

5.1.5 If during the period of controlled operation it is established that the equipment has defects that can lead to emergency consequences, or the operation of the equipment in any modes is characterized by a deviation from the permissible parameters and further operation is impossible, and the elimination of defects requires taking it out for repair for five or more days, then the equipment must be taken out of operation and it is rated "does not meet the requirements of the RTD". After the repair, to eliminate defects, the equipment is re-accepted from the repair, under controlled operation, and a new quality assessment is established for the repaired equipment.

5.1.6 A quality rating is established for each type of repaired equipment.

The quality assessment of the repaired installation is usually established by assessing the quality of the main equipment, taking into account the quality assessments established auxiliary equipment, which is part of the installation, which can limit the power, efficiency and reliability of the installation as a whole during subsequent operation.

5.2 Evaluation of the quality of the repair work performed

5.2.1 Assessment of the quality of the repair work performed characterizes the organizational and technical activities of each of the organizations involved in the repair.

For the quality of the repair work performed by the organization, one of the following ratings can be established:

- Great;

- Fine;

- satisfactory;

- unsatisfactory.

5.2.2 The assessment of the quality of the repair work performed is established by each organization within the scope of the equipment repair performed by it, taking into account the fulfillment by this organization of the basic and additional requirements.

The main requirements include:

- implementation of the agreed list of planned repair works, updated based on the results of defect detection;

- fulfillment of the requirements of the NTD for the repair of equipment and its components;

- lack of assessments of the quality of the repaired equipment "does not meet the requirements of the RTD" or "complies with the requirements of the RTD with a restriction" due to the fault of the repair contractor;

- no shutdowns of the equipment during the period of controlled operation due to the fault of the repair contractor, except for the need for one shutdown of the boiler or the boiler body for up to three days to eliminate defects in the welding of pipe joints that emerged during the period of controlled operation, and also with the exception of the need for shutdowns provided for during the period of controlled operation to monitor the condition of repaired critical components, to carry out adjustment and adjustment, including vibration, to balance the turbine unit shaft line in its own bearings.

Additional requirements include:

- availability of the necessary set of repair documentation;

- the use of the necessary technological equipment, fixtures and tools provided for by the technological documentation, and the compliance of their parameters with passport data;

- compliance of the performed technological operations, including control ones, with the requirements of technological documentation;

- holding input control used in the repair of materials and spare parts;

- availability of a complete set of executive and reporting documentation for repairs.

5.2.3 The grade "excellent" is set when all basic and additional requirements are met.

The grade "good" is set when all the main and partial fulfillment (at least 50%) of additional requirements are met.

The grade "satisfactory" is set when all the main and partial fulfillment (less than 50%) of additional requirements are met.

The rating "unsatisfactory" is established when one or more of the main requirements are not met.

5.2.4 The repaired equipment may have a quality rating - "complies with the requirements of the NTD with a restriction" for the following reasons not related to the quality of the repair organizations:

- power reduction associated with the combustion of non-design fuels and fuels of poor quality, restrictions on draft and blast, restrictions on the circulating cooling water of turbine condensers;

- lack of necessary spare parts and materials;

- the presence of structural defects, the consequences of accidents and the inability to perform the required amount of work;

- other reasons not related to the quality of the repair organization.

In such cases, the assessment of the quality of the repaired equipment - "complies with the requirements of the NTD with a restriction" does not affect the assessment of the quality of the repair work performed by the repair organization.

5.3 The procedure for assessing the quality of repairs

5.3.1 Assessment of the quality of equipment repair is carried out during the repair process and upon acceptance of equipment from repair.

5.3.2 The procedure and procedure for monitoring and assessing the quality of repaired equipment and the quality of repair work performed is presented in Table 1.


Table 1 - Order and procedure for monitoring and assessing the quality of repairs

Stage name

List of performed works

Executor

Documentation

In the process of repairing the installation (power unit)

Input control of materials and spare parts used in the repair.

Defective equipment components.

Clarification based on the results of fault detection of the scope of repairs.

Quality control of the repaired components, which consists in checking their compliance with the requirements of the NTD, technological and design documentation.

Quality control of the performed repair work. Checking compliance with technological discipline.

Work managers of enterprises and organizations involved in the repair, together with responsible representatives of the operating organization

The results of the input control, certificates for the materials and spare parts used in the repair process.

Executive documents for fault detection of equipment.

A list of additional repair work and a work exclusion protocol.

Act on the use of substitute materials.

Technical solution protocol for identified but not eliminated defects.

Test reports, measurement charts

Acceptance of the repaired equipment, control, testing and testing before presentation of the acceptance committee

Acceptance: responsible representatives of the operating organization.

Testing, testing: under the guidance of a responsible representative of the operating organization with the participation of repair contractors

Sampling protocols certain types equipment included in the installation, protocols on hydraulic tests and etc.

Protocols for hidden works.

List of completed repairs.

Other documents as agreed by the operating organization with the repair contractors

Permission to start the installation (power unit)

Monitoring the results of inspection of the installation (power unit), testing and testing of equipment, verification and analysis of documentation drawn up during the repair

Order of the technical manager of the power plant on the start-up of the installation (power unit).

The launch is carried out after the repair contractors have submitted a work permit for repairs

Operational personnel in the presence of repair managers or persons appointed by them

Before start-up, the repair work supervisors submit to the authorized representative of the operating organization the requirements in writing about the features of start-up and testing during acceptance tests that do not contradict the PTE

Acceptance tests

Start-up tests

Control over the operation of the installation (power unit).

Testing and testing of equipment in accordance with the program of acceptance tests.

Identification of defects.
Elimination of detected defects that require immediate shutdown

Operational journal, statements of quality indicators.

Note - Statements of quality indicators are compiled in accordance with the table given in 7.10 in Figure 5 of this standard

Load test (within 48 hours)

Checking equipment in operation under load at nominal parameters.

Testing of equipment in accordance with the program of acceptance tests.

Determination of a part of the quality indicators of the repaired equipment.

Identification of defects.
Elimination of detected defects that prevent the equipment from operating at rated load or require immediate shutdown

Operating personnel with the participation of repair performers

Operational log, statements of quality indicators

End of repair

The end of the repair is the time when the generator is connected to the network or when the boiler is connected to the station's live steam pipeline. If, during acceptance tests, defects were found that prevent the operation of the equipment with a rated load, or the defects found require an immediate shutdown, then the repair is considered incomplete until these defects are eliminated.

Acceptance from the repair of equipment included in the installation

The results of acceptance tests, documents drawn up by the repair contractor are considered

A decision is made on acceptance from repair.

Monitoring the fulfillment of the requirements and criteria that determine the assessment of the quality of the repaired equipment and the quality of the repair work performed.

Preliminary estimates of the quality of the repaired equipment included in the installation are established.

Preliminary estimates of the quality of the repair work performed are established.

Warranties accepted.

The results of the commission's work are documented by an act for acceptance from repair of equipment included in the installation, which is signed within 5 days after the completion of acceptance tests

Certificate of acceptance from the repair of equipment of the installation. Protocols, certificates, statements and other documents drawn up by the operating organization and the repair contractor and reflecting the following are attached to the act:

List of completed planned works;

List of works performed in excess of the planned volume;

List of outstanding works and reasons for their non-fulfillment;

List of directive documents, the requirements of which are met during the repair;

Modernization works;

The list of works performed with a deviation from the established requirements, the reasons for the deviations.

The act can be drawn up for a group of individual types of equipment included in the installation, or various components of the main equipment repaired by one enterprise

Preliminary quality assessment

Preliminary assessment of the quality of the repaired equipment included in the installation

Monitoring compliance with the requirements of regulatory and technical documentation that determines the quality of the repaired equipment.

Checking the elimination of identified defects.

Analysis of the results of acceptance tests. Comparison of quality indicators with normative ones. Establishing a quality assessment for repaired equipment

Acceptance committee headed by an authorized representative of the operating organization

The assessment of the quality of the repaired equipment is recorded in the certificate of acceptance from the repair of the equipment of the installation. If the equipment is rated "complies with the requirements of the NTD with a restriction", then an action plan is developed to eliminate the identified shortcomings, indicating the timing of its implementation

Preliminary assessment of the quality of the repair work performed

Monitoring the fulfillment of basic and additional requirements.

Establishing an assessment of the quality of the repair work performed:

For each type of repaired plant equipment included in the acceptance report;

Repair company for the entire scope of work performed by him on the unit

Acceptance committee headed by an authorized representative of the operating organization

The assessment of the quality of the repair work performed is recorded in the act for acceptance from the repair of the equipment of the installation

Acceptance from plant repair

Consideration of the results of acceptance tests and documents drawn up for the equipment that is part of the installation. Deciding on the acceptance of the installation from repair. The results of the commission's work are documented by an act for acceptance from the repair of the installation. The act is signed within 5 days after the completion of acceptance tests. The act includes preliminary assessments of the quality of the repaired equipment that is part of the installation, and preliminary assessments of the quality of the repair work performed by the enterprises performing the repair. Preliminary quality assessments are accepted according to the acts of acceptance from the repair of the equipment of the installation.

The act of acceptance from repair of the installation contains requirements on the need for shutdowns during the period of controlled operation to control critical components, to carry out adjustment and adjustment. These shutdowns do not affect the assessment of the quality of the repair work performed.

Acceptance committee headed by the technical manager of the power plant

Certificate of acceptance from the repair of the installation

Controlled operation of repaired equipment.

Start - after completion of acceptance tests.

End - after 30 calendar days from the moment the equipment is turned on under load

Checking the operation of equipment in all modes, testing and adjustment, determining the quality indicators of repaired equipment. Carrying out the shutdowns provided for in the certificate of acceptance from the repair of the installation

Operating personnel with the involvement, if necessary, of repair contractors

Quality score sheets

Re-repair

Detection on the equipment during the period of controlled operation of defects that can lead to emergency consequences or deviations from the permissible parameters, characterizing the impossibility of further operation in accordance with the requirements of the PTE (the duration of repairs to eliminate defects is at least 5 days). The equipment is decommissioned and subject to repair to eliminate defects. After repair, re-acceptance from repair is carried out, controlled operation

Operating personnel, repair contractors

The equipment is rated "does not meet the requirements of the NTD". After re-acceptance, a new quality assessment is established for the repaired equipment.

The repair company, through the fault of which the repeated repair occurred, is assessed the quality of the repair work performed - "unsatisfactory"

Final assessments of the quality of the repaired equipment included in the installation and the repair work performed

Analysis of the results of controlled operation of equipment.

If the owner or operating organization, based on the instructions of the state control bodies, based on the results of the inspection, gives a conclusion on a change in the quality assessment of the repaired equipment, the power plant is obliged to inform the repair contractor about this within three days after receiving the act indicating the reasons for the change and call his representative to make an agreed decision

Acceptance committee headed by an authorized representative of the operating organization

The preliminary quality assessment is considered final if the operating organization has not informed the repair contractor of its change. If, based on the results of the controlled operation, the operating organization considers it necessary to change the preliminary quality assessments, then it is obliged to inform the repair contractor about this within 3 days after the end of the controlled operation, indicating the reasons for the change and call his representative to make an agreed decision. The final quality assessments are recorded in the act for acceptance from the repair of the equipment of the installation

Assessment of the quality of the repaired installation as a whole

Analysis of the results of the controlled operation of the plant as a whole and the equipment of the plant. Analysis of the assessments of the quality of the repaired equipment that is part of the installation

Acceptance committee headed by the technical manager of the power plant

The assessment of the quality of the repaired unit is recorded in the certificate of acceptance from the repair of the unit after the end of the controlled operation.

Preparation of reporting documents for repairs

By the end of the controlled operation, the reporting documentation for the repair is fully drawn up and provided to the operating organization.

Repair contractors

All documents drawn up in the process of repair, acceptance tests and controlled operation by repair contractors

At the end of the controlled operation, within 10 days, the operating organization completes the reporting documentation for the repair

Operating organization personnel

All documents drawn up in the process of repair, acceptance tests and controlled operation

Note - In Table 1 and Figure 1, the "technical manager of a power plant" is a person in the staff of the operating organization authorized to make decisions and give orders on all technical issues related to the equipment and facilities of this power plant.


The table shows the stages of assessing the quality of repairs in their technological sequence, the list of works performed at each stage, the performers and the documentation drawn up at the same time.

5.3.3 The concept of quality assessment is shown in Figure 1.

Figure 1 - Schematic diagram of repair quality assessment

Picture 1 - circuit diagram repair quality assessment

6 General requirements for methods for assessing the quality of repair of power plant equipment

6.1 The methodology for assessing the quality of repairs for various types (types) of equipment of power plants is based on a unified methodology, according to which the assessment of the quality of repairs of a particular type (type) of equipment of power plants includes two components:

- methods for comparing quality indicators of repaired equipment;

- methods for assessing the fulfillment of the requirements of the NTD during the repair of equipment.

The block diagram of the methodology for assessing the quality of repairs is shown in Figure 2.
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To manage the quality of repair and maintenance processes, enterprises are implementing a comprehensive quality management system, expressed in the unity of technical, organizational, economic and social measures.

Technical measures include the improvement of technological preparation, as well as repair production, all types of quality control of the work carried out to repair and restore fixed assets, adherence to standards.

Economic activities should be aimed primarily at assessing economic efficiency methods for improving the quality of repair and maintenance, the use of various progressive forms of remuneration, the development of the creative activity of production workers, and the improvement of forms of labor organization at the sites.

Among social measures it is necessary to include the increase production qualification, improvement of labor protection, strengthening of labor discipline.

Organizational measures include improving the structure and organization of repair and maintenance processes.

The most important, in terms of quality assurance, are activities aimed at improving the organization and strengthening the control of repair and maintenance processes.

To ensure the quality of repair and maintenance, it is important that it is properly organized in accordance with local requirements.

Repair and maintenance work is carried out by specially trained personnel. Repair performers must be certified and have a qualification group of at least the third in terms of knowledge of the rules of operation and safety. Repair shop workers should be provided with schedules of inspections and checks carried out as part of repairs and maintenance, repair and maintenance instructions, and inspection logs.

One of the main and effective forms of control over the quality of repairs and maintenance is the daily analysis of the records of operational logs and inspection logs by the head, deputy head of the shop or senior foreman.

It is advisable to establish a strict procedure in which these persons should start their working day by going around the operational and maintenance areas, viewing the relevant logs, records and messages. Appropriate records should be made about the measures taken in the logs and maps. This procedure ensures prompt elimination of noticed malfunctions, prevention of failures, accidents and defects in equipment operation.



At most industrial enterprises, when equipment and machines are handed over for repair, the repair service draws up a defective list, in which they sequentially enter those malfunctions and defects that must be eliminated during repair. The nomenclature and level of these problems are established and determined most often on the basis of personal experience and intuition of the compiler of this statement. Further, upon completion of the repair and putting the equipment into operation, the elimination of these defects is checked and the quality of the repair is assessed.

The most important form of work aimed at establishing the quality of repair is the control of equipment for the so-called technological accuracy after repair. This applies most often to technological equipment enterprises. But the principles and techniques of such verification can be applicable (and are applied) to all groups of fixed assets. Such an inspection simultaneously includes a number of the following control operations:

1. Checking the overall quality of the repair. Here, those parameters are controlled, the evaluation of which can be determined visually. This is the correct pairing of all components and parts, completeness, the presence of various indicative inscriptions, tables, operating modes, diagrams, safety and blocking devices, devices, safety fences, appearance.

2. Checking and evaluating the operation of equipment at idle and under load. Here, the correctness and reliability of the operation of the equipment in general, the operation of all controls, protection systems, and lubrication are checked.

3. Checking and evaluation of stiffness, vibration, noise and other parameters of the equipment according to the established regulatory documents (if any). For some equipment, they can be indicators of the technical condition and quality of equipment repair.



4. Verification for technological accuracy or verification of basic technical parameters for compliance with passport data. They can be produced according to all the main parameters of the relevant equipment using instrumentation.

In addition to these checks, when assessing the quality of repair of fixed assets, testing work is usually carried out in accordance with various rules. technical operation and safety technology. Sometimes enterprises carry out work on the analysis of equipment downtime, accounting and analysis of accidents and defects. For some equipment, there are clearly established scopes and test standards that can be attributed to certain types of repairs.

The listed control operations and activities are an effective tool aimed at managing the quality of repairs. But at the same time, they do not reflect all aspects of the quality of repairs, which would be based on the principle of "measurement - comparison - evaluation". Therefore, some general indicators and methodology are needed to evaluate the results of maintenance and repair of fixed assets. When establishing such overall indicators must be taken into account, in addition to the rules for technical operation and safety regulations, the current regulations, such as GOST 2.602 - 68, GOST 20831 - 75. At the same time, the recommended GOST 2.602 - 68 - the rules for drawing up and maintaining repair documents, can serve as a basis for determining and setting indicators and developing a methodology for assessing the quality of repair work by repair services. GOST 20831 - 75 applies to the assessment of the quality of repaired products machine-building plant. But some provisions of this standard can be taken into account when establishing methods and methods for assessing the quality of repair of fixed assets at all enterprises.

Thus, the effectiveness of repair work can be assessed on the basis of the quality indicators of these fixed assets, on the factors that characterize the repair and determine the quality of the repaired fixed assets, as well as on the defectiveness indicators of the repaired products.

However, the analysis of these methods, as well as the essence of efficiency assessment in the framework of the implementation of the process approach at the enterprise, lead to the realization of the need for continuous improvement, the search for specific indicators and methods for assessing the quality of repair and maintenance of fixed assets for continuous improvement of the organization of such processes.

UDC 658.58

METHODOLOGY FOR ASSESSING THE QUALITY OF THE PROCESS MAINTENANCE AND REPAIR OF METAL-CUTTING MACHINES

A.V. Fedorov

A methodology for assessing the quality of the process of maintenance and repair of metal-cutting machines has been developed and a practical example of its use in working conditions industrial enterprise.

Keywords Keywords: quality, service, process, machine tools, repair.

Modern concept General Management quality (TQM) and international standards ISO 9000:2000 emphasizes the process approach, according to which manufacturing process on industrial enterprises it is proposed to consider as a network of interconnected and interacting processes, which should be managed according to the Deming-Shewhart PDCA (Plan-Do-Check-Act) cycle (Fig. 1), which includes the functions of planning, execution, quality control and regulation for each process.

Managing an organization as a network of processes makes it necessary to control the quality of the implementation of each of its constituent processes. According to , process quality control is understood as the measurement of controlled process parameters and their comparison with established requirements to determine compliance or non-compliance. Based this definition, we can conclude that for the implementation of the process quality control function in the PDCA cycle, it is necessary to have measurable process parameters (its characteristics to be measured and controlled).

process indicators;

process product indicators;

process customer satisfaction indicators.

Each of the listed groups of indicators can be manifested in cost, technical and time terms. Cost, time and technical indicators, in turn, can also be distributed by employee, site, workshop, sub-process, function levels.

For the main business processes of the enterprise, the direct result of which is the release of products, carrying out activities to identify the characteristics of the processes to be measured and controlled in the PDCA cycle is usually not difficult. But when identifying the measured parameters for auxiliary processes,

ny with maintenance (TO) and repair of metal-cutting machines, providing the main production with equipment, fixtures, cutting and measuring tools, i.e. contributing to the normal flow of the main business processes of the enterprise, certain difficulties arise.

For example, in fig. 2 shows a matrix that takes into account the relationship between the measured parameters of one of the most important auxiliary processes at industrial enterprises - the process of maintenance and repair of machine tools and the requirements for quality control.

As can be seen from fig. 2, the quality of the maintenance and repair process cannot be comprehensively assessed for all elements of the matrix, since they are absolute indicators of the process and its product (serviceable equipment) and are expressed in quantitative form. Therefore, indicators for assessing the quality of the process cannot be taken from operational data. They should be defined as relative values, i.e. like ratios. In this case, the conditions contained in the root columns of the matrix should be taken into account.

Based on the foregoing, the following parameters were chosen as the measured parameters for a comprehensive assessment of the quality of the maintenance and repair process:

indicators of efficiency and effectiveness (PER) of the repair service;

material damage to the main production from equipment downtime and unscheduled repairs.

Registration of the values ​​of the measured parameters with a certain

periodicity should be made in the monitoring maps of the process of maintenance and repair of metal-cutting machines.

Measured parameters of the maintenance and repair process

ISO 9000 Cost indicators Time indicators Technical indicators

Process indicators Total cost of inventory Cost of subcontracts, labor costs for RS personnel Total time spent on repair work Level of technical equipment of the RS, progressivity of the equipment

Process product indicators Cost of repairs for a specific piece of equipment Time for the subsequent operation of equipment Technological accuracy

Process consumer satisfaction indicators Total cost of repair work, share of repair costs in the cost of production Time for troubleshooting and troubleshooting Number of complaints, equipment failures

Maintenance and repair process monitoring map

STP for the maintenance and repair process

Requirements for the owner of the process to analyze deviations from the normal course of the process and document these deviations

Requirements for reviewing the effectiveness of corrective actions

Requirements for the formation of reporting on the process for a higher manager

Requirements for determining the planned values ​​of process indicators for the next period

Rice. 2. Quality parameters of the maintenance and repair process

Obviously, the most important quality parameter for the maintenance and repair process is PER, as it reflects the degree of compliance of the actual results of the process with the planned ones, as well as the relationship between the achieved result and the resources used. PERs also have the advantage that they can be used as a tool for continuous process monitoring.

As a PER, a number of technical and economic indicators of the repair service were selected, which fully satisfy the conditions of the matrix (Fig. 2).

To obtain a visual representation of the quality level of the maintenance and repair process, it is advisable to use pie charts in monitoring maps built on the relative technical and economic indicators of the quality of the maintenance and repair process, and their weight coefficients (Fig. 3).

Each indicator is depicted on the diagram as a circular sector, the radius of which q is equal to the value of the indicator relative to the selected analog, and the central angle is the weight coefficient, expressed as a conditional value in degrees or radians. The base values ​​for all indicators are represented by a circle with a radius equal to one. The central angle for the I-th indicator with the weight coefficient aI is defined as

The quality level of the maintenance and repair process is determined on the basis of a complex weighted average of the Vk indicator, referred to here as a weighted average of the circular indicator. It is equal to the radius of a circle whose area is equal to the sum of the areas of the chart sectors. It can be calculated using the formula

Rice. 3. How to build a pie chart

where n is the number of relative indicators of the quality of the maintenance and repair process; w - weight coefficient; q - the value of the i-th indicator.

Experience shows that Wc is close to the weighted arithmetic average: deviations of Wc from this indicator in a wide range of changes in relative indicators and weighting factors do not exceed 10%.

The value of the average weighted circular indicator is graphically displayed as a circle in the form of a dotted line (Fig. 3). UK< 1 означает, что уровень качества процесса ниже условного относительного аналога. Предлагаемый здесь средний взвешенный круговой показатель для широкого диапазона изменений относительных показателей и коэффициентов весомости имеет значения, близкие к значениям среднего взвешенного арифметического показателя. Более того, он обладает важным преимуществом по сравнению с арифметическим показателем. Оно заключается в том, что круговой показатель имеет геометрический смысл: он равен радиусу круга, площадь которого равна сумме площадей секторов диаграммы.

Weighting factors for all indicators in each enterprise should be assigned using expert assessment methods and adjusted when compared with past results. The PERs themselves are also selected by a specially created expert group, depending on the features of the maintenance and repair process and the current balanced system indicators (BSC) at each enterprise, and after a certain period of registration of indicators, the manager of the maintenance and repair process should determine the standard and target values ​​\u200b\u200bfor each of them.

When determining the material damage to the processes of the main production from unscheduled repairs and equipment downtime, the monitoring map of the maintenance and repair process should take into account the indicators of the use of labor and equipment. Then the amount of actually caused damage (Mu) with a sufficient degree of certainty can be determined by the amount of material losses due to downtime of equipment (Mo) and workers (Mp).

Mu = I Mp + £ Mo, (2)

where n is the number of workers taken into account; m is the amount of equipment taken into account.

To file claims for each specific case of violations of the conditions of production, a special act is drawn up for an economic claim. If the costs of claims are recognized by the guilty service

ba, then the claim signed by the parties is transferred by the interested party to the planning and economic service of the enterprise. Further, the correctness of the calculations made is checked, and the amount of expenses is reflected in the reports of the relevant departments.

To automate the task of managing the process of maintenance and repair of metal-cutting machine tools according to the RBSL cycle, a computerized system for its scheduling and control was developed, which includes a module for monitoring the quality of the process. On fig. 4 shows a pie chart constructed by this automated system and characterizing the quality of the process of maintenance and repair of metal-cutting machines at the Branch "Rudakovsky Mechanical Plant" of JSC "Tulatochmash".

№ Indicator Value

01.2013 02.2013 03.2013 04.2013

1. Degree of failure rate 0.744 0.756 0.810 0.797

2. Share of salary of repairmen in maintenance and repair costs 0.925 0.894 0.914 0.873

3. Time lost due to breakdowns 0.870 0.886 0.895 0.871

4. Degree of development of subcontracts 0.801 0.843 0.900 0.850

5. Operational readiness ratio 0.635 0.667 0.685 0.661

6. Availability of spare parts 0.691 0.689 0.751 0.720

7. Degree of equipment loading 0.740 0.762 0.792 0.753

UK 0.778 0.790 0.825 0.793

Rice. 4. Pie chart of the quality level of the maintenance and repair process in March 2013 at the Branch "Rudakovo Mechanical Plant"

OJSC "Tulatochmash"

The diagram shows those PERs that most fully take into account the relationship of equipment operation with the amount of labor and spare parts at the enterprise. Monitoring maps compiled by an automated system for scheduling and monitoring the process of maintenance and repair of metal-cutting machines allow the manager to monitor the quality of this process, i.e. receive a signal when various inconsistencies occur during maintenance, conduct systematic comparisons with past results and find out trends in parameter changes, judge the results of the work of various units of the repair service.

The application of the proposed methodology for assessing the quality of the process of maintenance and repair of metal-cutting machine tools is successfully used at the Branch "Rudakovskiy Mechanical Plant" of JSC "Tulatochmash" and can contribute to the real implementation of the principles of the process approach and TQM at

other domestic industrial enterprises.

Bibliography

1. Quality management: Textbook for universities / S.D. Ilyenkova, N.D. Ilyenkova, V.S. Mkhitaryan and others; ed. S.D. Ilyenkova. 2nd ed., revised. and additional M.: UNITI-DANA, 2003. 334 p.

2. Antsev V.Yu., Fedorov A.V., Dolgov V.V. Management of the process of maintenance and repair of metalworking equipment // Handbook. Engineering Journal. No. 8. 2004. S. 55-58.

3. Zheleznov G.S. Graphical representation of the level of product quality // Methods of quality management. 2002. No. 12. S. 26 - 27.

4. Antsev V.Yu., Trushin N.N., Fedorov A.V. Resolving Uncertainties in Technological Design Problems Based on the Method of Expert Evaluations // Technological System Engineering. Sat. Proceedings of the First International Electronic scientific and technical conference. Tula: Grif and Co, 2002, pp. 229 - 233.

5. Litvak B.G. Expert assessments and decision making. M. "Patent", 1996. 56 p.

6. Statistical Methods analysis of expert assessments. M.: Nauka, 1977. 384 p.

7. Management and marketing. Volume 2. Textbook / ed. A. Zhichkina. M.: "European Center for Quality", 2002. 200 p.

Fedorov Alexey Valentinovich, Ph.D. tech. Sciences, Associate Professor, Russia, Tula, Tula State University

METHOD OF EVALUATION OF QUALITY OF SERVICE AND REPAIR MACHINE TOOL

Developed a method of assessing the quality of the process of maintenance and repair of machine tools and a practical example of its use in the production of an industrial enterprise.

Key words: quality, service, process, machine, repair.

Fedorov Alexey Valentinovich, candidate of technical science, docent, Russia, Tula, Tula State University

Any job technical system can be characterized by its efficiency (Figure 1.5), which is understood as a set of properties that determine the ability of the system to perform certain tasks when it is created.

Figure 1.5 - Main properties of technical systems

In the general case, the problem of optimizing the frequency of maintenance is solved from the conditions of ensuring a given level of technical condition, equipment readiness, warranty period at minimal cost. With a broader formulation of the problem, it should be taken into account that only a reduction in the cost of maintenance does not guarantee the optimal choice of frequency. It is necessary to evaluate its effectiveness. The efficiency criterion is called an indicator that measures the costs incurred with the effect received from them. To evaluate the effectiveness of changing the frequency of maintenance, it is necessary to compare the economic effect with the required costs.

This problem can be solved using the methodology (basic provisions) for determining the economic efficiency of using in industry new technology and inventions. Efficiency analysis is based on comparing the economic results of using new and old technology. The main indicator of the economic efficiency of new technology is the economic effect, determined by the difference in the reduced costs of the base and new options.

With regard to the problem under consideration, at the first stage of assessing the economic efficiency new technology maintenance, it is necessary to compare the reduced costs, i.e., the sum of the cost and the standard profit when using the basic and new service technologies.

When calculating, comparability of the compared options for the new and basic service technology should be ensured in terms of the volume of work performed using the new technology, in terms of quality parameters and the time factor. The basic service technology in the first stage (research phase) should be taken as the best service technology developed in the country, which has the lowest reduced cost per unit of work. Since the maintenance technology is characterized by a change in current costs over the years of operation of the equipment, it is necessary to take into account the time factor, i.e., it is required to reduce to one point in time the one-time and current costs for the creation of new and old maintenance technology and its application.

An analysis of the economics of communications, motor transport, air transport and other types of equipment shows that operating costs are divided into costs associated with the performance of work on equipment, and costs associated with the organization and management of personnel work, maintenance of technological processes. Maintenance costs are part of the main operating costs associated with the use of equipment and vary in proportion to the duration of operation. Typically, maintenance costs include the cost of routine equipment, materials, wages and etc.

The cost (price) of service depends on the standards of material costs, the system of remuneration, productivity, technical equipment, production volume and other factors.

Maintenance costs are determined during the operation of the equipment by analyzing the actual costs. However, even for such mass types of equipment as cars and aircraft, there are no standards for the cost of their maintenance and current repairs. So, for aircraft, the cost of maintenance and current repairs is taken to be about 25% of the depreciation rate for 1 hour of flight. This circumstance is explained by the great complexity of collecting and processing statistical data on service costs.

However, data are known on the relationship between operating costs and the physical wear and tear of equipment. Such cost components are changes in the cost of repairs, downtime for repairs, the cost of replacing worn parts, changes in productivity and other characteristics of machines. Figure 1.6 shows the components of operating costs depending on physical wear and tear characterizing the nonlinear dependence of costs on physical wear.

The considered components also take place during maintenance, and the main reason for the change in these costs is the technical condition of the equipment.


Figure 1.6 - Dependence of operating costs on overhaul periods:

1 - costs from changing the characteristics of the product; 2- costs from repair costs, downtime; 3- costs of replacing worn parts; 4- total costs

The consequence of this change is a decrease in the reliability of machines, an increase in the cost of spare parts, maintenance work, etc., therefore, maintenance costs can be represented as a function of changes in the technical condition, and the features of the types of service (costs for wages, routine equipment, etc., service reliability) can be taken into account by special coefficients.



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