Quality control of finished products. Product quality control that cannot be neglected

In a broad sense, quality control is the sum of all measures to ensure a stable level of product quality. In a narrow sense, this term means a comparison of the actual value of a product with a given value, in which it is established to what extent the products meet the requirements established for them.

Quality Control- any planned and systematic activity carried out at a manufacturing enterprise (in a production system), which is implemented to ensure that the goods produced, services, and processes performed comply with the established customer requirements (standards).

In accordance with the ISO 9000: 2000 standard, which defines all such standards, quality is a set of certain characteristics and properties of a product or service to satisfy the identified needs. This definition turns quality into a value-neutral list of product characteristics (see Figure 1). It is important that the selected characteristics are measurable and controllable. These can include physical quantities (weight, temperature, density), as well as characteristics related to trade (price, number of pieces per lot, size of packaging), or to customers (for example, positive consideration of wishes). The characteristics can be very different, the two main subgroups are qualitative (for example, design) and quantitative (stroke height), each of which can be determined either precisely (for example, the piston stroke of the press is exactly 150 mm), or have a certain interval (the stroke of the press piston set in the range from 20 to 100 mm). In addition, there may be tolerances (150 mm plus minus 0.1 mm).

Diagram 1. An example of the concept of quality for a connecting hose.

Quality parameter	Requirements	Quality standard
		max. 507 mm - min. 497 mm
Diameter	Internal diameter di = 9 mm, Outside diameter d a = 16 mm	Max. 507 mm - min. 497 mm Max. 8.4mm - Min 7.4mm
External surface color	Different color is allowed	Specified value
Bending radius	Smallest bending radius 65 mm	Not less than 65 mm
Operating pressure

Quality control includes both project (design) control and manufacturing verification, which may differ in the volume of control activities carried out during continuous control and in the sample size during selective control. Sampling control (statistical) gives indications of the state of the production process either using statistical methods (production control), or using the obtained data on the proportion of defective products in the volume of a production batch.

Types of quality control

Thus, a distinction is made between sample, solid and statistical types. Solid All products undergo control, in production they keep a record of all defects arising in the process of manufacturing the product.

Selective- control of a part of the product, the results of which are valid for the entire batch. This type is preventive, from here it is carried out throughout the production process in order to prevent the occurrence of defects.

Incoming control- quality control of raw materials and auxiliary materials entering production. Constant analysis of the supplied raw materials and materials allows you to influence the production of supplier enterprises, seeking to improve quality.

Interoperational control covers the entire technological process. This type is sometimes called technological, or current. The purpose of interoperational control is to check compliance with technological regimes, storage and packaging rules for products between operations.

Output (acceptance) control- quality control of finished products. The purpose of the final inspection is to establish the conformity of the quality of finished products to the requirements of standards or technical specifications, to identify possible defects. If all conditions are met, then the delivery of products is permitted. Quality Control Department also checks the quality of packaging and the correctness of labeling of finished products.

7 tools

There are the following quality control tools ( ):

Summary map of defects;
Bar graph;
Quality control map;
Brainstorm;
Correlation chart;
Pareto chart.

Closely related to technically oriented quality control is an economically oriented approach. Technical parameters should never be considered apart from economic ones. Technical innovation occurs precisely where economists see a good opportunity to cut costs or a great potential for increasing profits. Improvement potential is only assessed when there is a clear economic analysis together with the technical data. International standard ISO 9000: 2000 defines quality costs as "costs that arise to ensure the desired quality and convince the consumer that the product will satisfy his needs, as well as losses if it is insufficient." Figure 2 gives an idea of how they are subdivided:

Scheme 2. Structure and classification of quality costs

The cost of a defect is determined by whether it was discovered in production or whether it was a consumer complaint. Typical internal waste costs are:

waste, defective products;
processing of marriage;
unplanned sorting;
researching the problem;
repeated checks;
additional costs of time due to the need for unintended control.

Typical external costs of marriage are:

replacement costs for defective goods
maintenance and repair of defective goods
expenses arising from the fact of providing a guarantee
the cost of the product warranty.

In most cases, it makes sense to subdivide the cost of marriage into the cost of identifying the marriage, the cost of eliminating the marriage, and the costs that resulted from the marriage.

The costs of conformity include the costs necessary to achieve compliance between the planned and available quality, for certification - all costs that are associated with the documentation of activities. This includes the cost of certifying quality management systems or the cost of software that facilitates the distribution of documents throughout the enterprise. Control costs are usually understood as the costs of carrying out control measures before the start, during the production process and control of finished products, as well as the costs of all other quality control tools... This could also include the external costs of providing guarantees, obtaining permits, etc. The cost of preventing scrap is planning, metrics research, supplier evaluation, auditing, and staff training. This also includes the cost of maintaining production.

Practical examples of the use of quality control can be found in Almanac "Production Management"

NON-STATE EDUCATIONAL INSTITUTION OF HIGHER PROFESSIONAL EDUCATION

"ELABUZH CITY INSTITUTE OF INNOVATIVE TECHNOLOGIES"

Engineering and technical faculty

Department of Quality Management

Test

by discipline: "Means and methods of quality management"

on the topic: "Incoming product quality control"

Elabuga 2011

Introduction

The concept and types of product quality control

Incoming control of product quality, definition, concept of purpose, main tasks, organization of incoming control, efficiency

Conclusion

Introduction

Relevance. Quality control is one of the main functions in the quality management process. It is also the most voluminous function in terms of the methods used, to which a large number of works in various fields of knowledge are devoted. The importance of control lies in the fact that it allows you to identify errors in time, in order to quickly correct them with minimal losses.

The purpose of this work is to consider quality control, as well as to define the concept of incoming product quality control, its purpose, main tasks, the organization of incoming control and efficiency.

The test consists of an introduction, 4 chapters, a conclusion, which summarizes all the conclusions of the work and a list of references.

The first chapter discusses the concept and types of product quality control. In the second chapter, the input quality control of products, definition, concept is considered. Purpose, main tasks, organization and effectiveness of incoming product quality control, it is discussed in the third chapter. And how the incoming quality control of metal products is carried out at the enterprises is discussed in the fourth chapter.

quality control standard metal products

1. Concept and types of product quality control

Quality control is understood as checking the conformity of the quantitative or qualitative characteristics of a product or a process on which the quality of the product depends on the established technical requirements.

Product quality control is an integral part of the production process and is aimed at checking the reliability in the process of its manufacture, consumption or operation.

The essence of product quality control at the enterprise is to obtain information about the state of the object and compare the results obtained with the established requirements fixed in the drawings, standards, supply contracts, technical specifications. NTD, TU and other documents.

Control involves checking products at the very beginning of the production process and during the period of operational maintenance, ensuring, in the event of deviations from the regulated quality requirements, that corrective actions are taken to produce products of adequate quality, proper maintenance during operation and full satisfaction of customer requirements. Thus, product control includes such measures at the place of its manufacture or at the place of its operation, as a result of which the admitted deviations from the norm of the required level of quality can be corrected even before the defective products or products that do not meet the technical requirements are released. Insufficient control at the stage of production of serial products leads to financial problems and entails additional costs. Quality control includes:

incoming quality control of raw materials, basic and auxiliary materials, semi-finished products, components, tools supplied to the warehouses of the enterprise;

production operational control over compliance with the established technological regime, and sometimes interoperational acceptance of products;

systematic monitoring of the condition of equipment, machines, cutting and measuring tools, control and measuring devices, various measuring instruments, stamps, models of testing equipment and weighing facilities, new and in operation devices, conditions of production and transportation of products and other checks;

control of models and prototypes;

control of finished products (parts, small assembly units, sub-assemblies, assemblies, blocks, products).

Incoming product quality control, definition, concept

appointment, main tasks, organization of incoming control,

efficiency

Incoming control of product quality should be understood as control of the quality of the supplier's products received by the consumer or customer and intended for use in the manufacture, repair or operation of products.

These recommendations establish the basic provisions for the organization, conduct and registration of the results of incoming inspection of raw materials, materials, semi-finished products, components, etc., coming from suppliers to the consumer.

The recommendations were developed with the aim of providing methodological and practical assistance to the company's specialists in the implementation and use of a product quality management system based on the application of international standards MS ISO 9000 series.

The main tasks of incoming control can be:

obtaining with high reliability an assessment of the quality of products submitted for control;

ensuring the unambiguity of mutual recognition of the results of product quality assessment by the supplier and the consumer, carried out according to the same methods and according to the same control plans;

establishing the conformity of product quality to the established requirements in order to timely present claims to suppliers, as well as for operational work with suppliers to ensure the required level of product quality;

preventing the launch into production or repair of products that do not meet the established requirements, as well as permission protocols in accordance with GOST 2.124. [GOST]

One of the elements of the relationship with the supplier is the organization of incoming control, which means quality control of the supplier's products (raw materials, components, information) received by the organization - the consumer and intended for use in the manufacture, repair or operation of products, as well as the provision of services. Its main purpose is to exclude the possibility of penetration into production of raw materials, materials, semi-finished products, components, tools, information with deviations from the quality requirements reflected in the contractual obligations. The imperfection of this type of control can bring significant losses to both the manufacturer of the product and its consumer.

Incoming control is very time consuming and expensive, while it duplicates the output control of the issuing enterprise. In this regard, the refusal of incoming control is becoming increasingly important due to the strengthening of outgoing control, which entails the establishment of special relations with the supplier. The practice of such relations has existed abroad for a long time. For example, at the Japanese firm Bridgestone Corporation, the supplied parts and raw materials are inspected mainly in order to check their quantity and compliance with the technical documentation. Checking the quality of materials is not carried out, since it is carried out by suppliers before being sent to the consumer. This system is based on mutual trust and cooperation.

In accordance with the terms of the supply agreement, incoming inspection can be either continuous or selective. For its implementation at industrial enterprises in the quality control system, specialized subdivisions are created. Incoming control laboratories function at medium and large enterprises. The main tasks of these divisions are:

conducting incoming quality control of material and technical resources entering the organization;

execution of documents based on the results of control;

control of technological tests (samples, analyzes) of incoming resources in workshops, laboratories, control and test stations;

control over the observance by warehouse workers of the rules for storing and issuing received products for production;

Calling representatives of suppliers to jointly draw up an act on defects discovered during the incoming inspection, etc. Demonstration of the effectiveness of incoming control is the reduction of cases of inferior quality material and technical resources or services entering production.

The forms of incoming control include:

Periodic monitoring of the effectiveness of the supplier's quality assurance system (the so-called “second party” audit);

The requirement for the supplier to accompany the shipment of goods with protocols of control procedures;

The requirement for the supplier to carry out one hundred percent control and testing of the supplied material and technical resources or services;

Selective acceptance tests of a batch of goods by the supplier and the consumer at the same time;

The supplier uses a formal quality assurance system defined by the customer (e.g. based on ISO 9000 standards) .;

Requirements for independent third-party certification of supplier products.

If we are guided by the international standard ISO 9001: 2008, then in section 7 "Production of products" in subsection 7.4 "Purchases" clause 7.4.1 reads: "The organization must ensure that the purchased products meet the established requirements for purchases. The scope and nature of management in relation to the supplier and purchased products should be determined by the degree of influence of these products on the subsequent production of products or on finished products. "

The organization shall evaluate and select suppliers based on their ability to supply products in accordance with the requirements of the organization.

Criteria for the selection, evaluation and re-evaluation of suppliers should be established. Records should be kept of the results of such an assessment and subsequent actions. ”

In clause 7.4.2 "Information for purchases" we read: "Information for purchases should contain a description of the ordered products and include, where necessary:

requirements for the approval of products, procedures, processes and equipment;

requirements for the qualifications of personnel;

quality management system requirements.

The organization shall ensure that specified purchasing requirements are adequate before communicating them to the supplier.

Finally, clause 7.4.3 “Verification (verification) of purchased products reads as follows:“ The organization shall determine and implement control measures or other activities necessary to ensure that the purchased product meets the requirements specified in the purchase information. In cases where the Organization or its customer intends to check (verify) purchased products at the supplier's premises, the Organization shall establish in the purchase information the intended measures for such verification and the method of product release. "

Incoming quality control of metal products

The main indicators of the quality of the metal are: chemical composition; micro- and macrostructure; basic and technological properties; dimensions, geometry and surface quality of metal products. Requirements for the quality of metal and products made from it are stipulated in national standards, technical specifications of firms (enterprises) or separate agreements between the consumer and the supplier. The quality of the metal and reliable methods for determining its main indicators are the main ones in the technological chain of production. The quality of metal products supplied to the enterprise is determined during the incoming inspection (VC).

Incoming inspection of metal products is mandatory at firms (enterprises) that develop or manufacture industrial products, as well as carry out their repairs. This control is organized and carried out in accordance with GOST 24297-87, as well as with the standards and other normative and technical documentation (NTD) of the enterprise.

Organization of incoming quality control of metal products:

In accordance with GOST 24297-87, the incoming control is carried out by the incoming control division - the incoming control bureau (BVK), which is part of the company's technical quality control service (OTK).

The main tasks of incoming control are:

control of the availability of accompanying documentation for products;

control of the conformity of the quality and completeness of products to the requirements of design and normative-technical documentation;

the accumulation of statistical data on the actual level of quality of the products obtained and the development of proposals on this basis for improving the quality and, if necessary, revising the requirements of the NTD for products;

periodic monitoring of compliance with the rules and shelf life of suppliers' products.

Incoming control must be carried out in a specially designated room (area) equipped with the necessary means of control, testing and office equipment, as well as meeting labor safety requirements. Measuring instruments and test equipment used for incoming inspection are selected in accordance with the requirements of the NTD for the controlled products and GOST 8.002-86. If the metrological means and control methods differ from those specified in the NTD, then the consumer agrees the technical characteristics of the used means and control methods with the supplier.

In order to ensure compliance with the requirements of GOST 24297, as well as the standards of the GOST R ISO 9000 series, taking into account the profile and characteristics of the products, its own NTD is being developed. For example, large enterprises develop enterprise standards (STP) "Incoming inspection of metallic materials", "Technological instructions (TI) for incoming inspection of metallic materials", etc.

STP establishes the procedure for organizing, conducting and formalizing the results of incoming inspection of metal products used at the enterprise. TI determines the scope and types of incoming inspection in accordance with the list of metals and semi-finished products subject to VC. The scope and types of incoming control are established in accordance with the NTD and technical specifications for the products.

The VC is the responsibility of the BVK. The entrance control involves: a warehouse of purchased metal products or a consumer workshop (hereinafter referred to as a warehouse) and a central factory laboratory (CPL).

Incoming inspection of metal products includes the following checks:

accompanying documents certifying quality (certificate, passport);

labeling, containers, packaging;

geometric dimensions;

surface conditions;

special properties;

grade of material (chemical composition), mechanical properties, structure.

A typical VC organization scheme (Fig. 3.1) is as follows. The metal products received at the warehouse are accepted with accompanying documentation on the nomenclature, assortment and quantity, and no later than 10 days are transferred to the incoming control. At the entrance control, checks are carried out on the first four points (see above) and samples are taken to confirm the metal grade, structure, mechanical and special properties. Sampling is carried out under the supervision of BVK. The selected samples are transferred to the Central Laboratory. Based on the data of the incoming inspection, including the conclusion of the Central Laboratory, a conclusion is made about the conformity of the quality of metal products to the established requirements.

Rice. 3.1. Typical scheme of organization of incoming control

If the results of the control are positive, a mark is made in the accompanying documentation (certificate, passport) "Incoming control has been carried out, corresponds to TI"

If any indicator does not meet the established requirements, a double number of samples from a given batch of metal is subjected to control. If unsatisfactory results are received again, the warehouse, BVK and the supply department draw up a defect certificate.

The rejected metal is marked with the red paint "Brak" and is stored in the reject isolator until a decision is made on disposal or return.

Control of geometric dimensions. The TI regulates the scope of control of the dimensions of the assortment of metal products, which is, as a rule, 5% of one batch. Dimension control is carried out by measuring instruments that provide a measurement error equal to ½ tolerance for the measured parameter.

Depending on the type of assortment (bar, tape, sheet, etc.), the dimensions specified in the certificate are subject to control, while the TI stipulates how and in what places the measurements are taken.

For example, the measurement of the thickness of strips and tapes should be carried out at a distance of at least 50 mm from the end and at least 10 mm from the edge. Tapes with a width of 20 mm or less are measured in the middle. Measurements are made with a micrometer in accordance with GOST 6507-90 or GOST 4381-87.

Measurement of the thickness of sheets and plates is carried out at a distance of at least 115 mm from the corners and at least 25 mm from the edges of the sheet with a caliper (GOST 166-89).

Measurement of the diameters of bars, wires is carried out in at least two places in two mutually perpendicular directions of the same section with a micrometer (wire) or a caliper (bar). The width and length are measured with a metal tape in accordance with GOST 7502-89 or a metal ruler in accordance with GOST 427-75.

Surface control. The quality of the metal surface is checked for compliance with the requirements of the NTD for delivery visually without the use of magnifying devices (unless otherwise specified). The recommended inspection volume is 5% of the lot. In some cases (forgings, castings, etc.), 100% of the product is subjected to surface control.

The most common characteristic defects of the surface of metal products are given in table. 3.1 and fig. 3.2.

Table 3.1 Surface defects of metal products

The name of the defect Types, origin and a brief description of the defect Effect of the defect on the quality of the semi-finished product or finished product Metallurgical defects Foams (Fig. 3.2, a) During pressure treatment, the walls of the bubbles and shells of the ingots are compressed, stretched and partially broadened. The outer walls of the chambers with increasing metal reduction become thin and break through. The resulting delamination of the metal, more or less parallel to the surface and extending onto it, is called captivity. Removal of captivity on semi-finished products, if their depth does not go beyond the dimensional tolerances, does not affect the quality of the product. Films on the surface of the tubes lead to rejection of products Cracks (Fig. 3.2, c, d, f, g) Cracks on the surface, as well as internal cracks, are the result of stresses arising from uneven heating, strong work hardening, burns during grinding and similar reasons Cracks, that do not take the semi-finished product outside the tolerances in size, refer to a correctable marriage. In the finished product, cracks cause rejection Bubbles (Fig. 3.2, b) If the outer wall of the finished bubble is very thin, then when the metal is heated, the gases inside the bubble expand, bulge the outer wall and form a bubble on the surface Shells Shells on the surface of castings are the result of unsatisfactory molding, cutting out defects , and in products obtained by processing by pressure, as a result of opened bubbles, etc. If the shell does not take the size of the product outside the established tolerances, semi-finished products with surface shells are considered a fixable marriage. In finished products, shells lead to rejection Burrs and sunsets Burr is a bulge along the rolling profile, resulting from the squeezing of metal from the stream into the gap between the rolls. Sunset is a burr rolled into metal during finishing rolling. Burrs are also found on stamped blanks when the halves of the cut-off die are displaced Finished rods and rods of profile metal are rejected in the presence of a burr or sunset. finished tubes leads to rejection of themWhite spots and stripesWhite spots and stripes are defects that occur mainly on aluminum products. They are the result of metal contamination with an electrolyte, the presence of non-metallic inclusions and impurities of sodium and calcium The defect sharply reduces the corrosion resistance of aluminum and aluminum products, and also spoils their appearance Sodium disease Sodium disease - the inclusion of sodium compounds in aluminum The defect converts aluminum products into rejects Ripples - dot imprints of depressions on the surface of aluminum Products caused by adhesion of aluminum to rolling rolls Chemical defects Strong chafing in thin-walled products leads to a significant decrease in the section of the walls. Grinding is a consequence of a high concentration of etching substances, as well as a long exposure of products in them. Under-etching is the result of etching with solutions of weak acids and alkalis or depletion of the bath, short exposure in the bath, as well as contact of products with each other during etching Matt Is the result of uneven etching caused by oil contamination during stamping, liquation inhomogeneity, etc. Rough spots Rough dark and white stains on light metal products indicate corrosion Mechanical defects Risks and galling Risks (longitudinal scratches) occur on the inner and outer surfaces as a result of poor polishing of the dies, the ingress of solid particles (sand, scale, metal shavings) into them, the ingress of the same particles into the drawing point when broaching, with non-smooth surfaces of profiles, dies, etc. Seizure results from pressing at high temperatures or at high pressing speed Defects spoil the appearance, reduce the dimensional accuracy of the manufactured products, and sometimes lead to rejects Torn and tear Torn and tear I They are the result of metal stiffness, defects in the stamping tool (sharp corners) and improper installation of dies Leads the product to rejects Wrinkles and folds Most often found on the bodies of drawn products and are vertically located thickenings from metal compression. These defects arise as a result of uneven thickness of the workpiece or the gap between the dies and insufficient preheating of the workpiece Damage the appearance and lead to the rejection of the finished product Roughs Unpolished areas of the products, on the bottom of which scale remains Defect contributes to the rapid wear of the product, spoils the appearance and interferes with work with a certain accuracy abrasive tools Reduce the life of the product and spoil the appearance of the surface. Grips on the cutting edge of the tool reduce the quality of its work Grooves Grooves - lines visible to the naked eye and going in the direction of rough grinding on finished products (tool) Grooves spoil the appearance, reduce corrosion resistance, and in some devices and tools affect the correct operation Flaking of metallic or non-metallic Flaking of metallic and non-metallic coatings is the result of their poor adhesion to the base metal of the nick (Fig. 3.2, e)

Rice. 3.2. Surface defects of metal products: a) seams; b) bubbles on the surface; c) cracks with strong work hardening; d) a crack caused by a grinding burn; e) nicks; f) hardening cracks; g) grinding cracks; (f and g - revealed by magnetic powder)

If it is necessary to control the inner surface of the pipes, samples are cut from them, cut along the generatrix and the presence of defects is monitored. In all cases, upon detection of defects (including traces of corrosion), samples are taken from the locations of these defects and sent to the central laboratory to determine the nature of the defect and its depth. According to the conclusion of the Central Laboratory, a decision is made on the suitability of a given batch of metal.

Control of chemical composition and mechanical properties. This control is carried out in the CPL on specially selected samples from each batch of metal with the execution of an opinion in the prescribed form.

Chemical composition control. This type of control is carried out in order to establish the compliance of the qualitative and quantitative chemical composition of metal products with the standards stated in the certificate.

The sampling rate for control of the chemical composition is set in the TI and is, as a rule:

for sheets and plates - from one control sheet, batch plate;

for tapes, strips, wire - from one control roll of the batch;

for bars and profiles that are individually stamped by the supplying plant - from one bar, profile, batch;

for bars and profiles marked on the tag - from 2, 3 and 5 bars, profiles for batches of less than 30 pcs., from 30 to 50 pcs. and over 50 pieces, respectively.

The selected samples are sent to the central laboratory, where the chemical composition is monitored using chemical and / or spectral methods of analysis.

Chemical methods of analysis, which are based on the chemical reactions of analytes in solutions, include mainly gravimetric, titrimetric and colorimetric analyzes. These methods are described in the relevant GOST. It should be noted that chemical analysis is laborious, is not universal, and does not have high sensitivity (especially at low concentrations of the elements being determined).

Spectral analysis is a physical method for the qualitative and quantitative determination of the composition of a substance from its spectra.

Spectrographs (ISP-30, DFS-13, DFS-8) and quantum meters (DFS-41, DFS-51, MFS-4, Papuas-4) are widely used for express and marking analysis of the chemical composition of steels, cast irons and nonferrous alloys. , which are based on the generally accepted scheme of emission spectral analysis. During the analysis, a pulsed electric discharge is initiated between two electrodes, one of which is the analyzed sample. The radiation of the atoms of the elements, which are part of the sample, excited in the discharge, passes through a polychromator with a concave diffraction grating and is decomposed into a spectrum. Each chemical element has its own set of spectral lines, the intensity of which depends on the concentration of the element in the sample.

In a qualitative analysis, the resulting spectrum is interpreted using tables and atlases of the spectra of the elements. For quantitative analysis of a sample, one or several analytical lines of each analyzed element are selected from the spectrum.

The intensity (J) of the spectral line of length l is related to the concentration (c) of the element in the sample by the dependence:

(l) = a × cb,

where a and b are quantities depending on the analysis conditions.

Modern instruments for spectral analysis, as a rule, are combined with a computer, which makes it possible to fully automate the analysis of spectra. In addition to these devices, steeloscopes (Fig. 3.3) of the "Spectrum" type are used at enterprises for quick visual qualitative and comparative quantitative analysis of ferrous and non-ferrous alloys in the visible region of the spectrum. The portable version of the steeloscope (SLS) allows such an analysis to be carried out in workshops, warehouses, on large-sized parts without destroying the surface.

Spectral analysis of metals is carried out according to GOST, namely:

steels - GOST 18895-81;

titanium alloys - GOST 23902-79;

aluminum alloys - GOST 7727-75;

magnesium alloys - GOST 7728-79;

copper - GOST 9717.1-82, GOST 9717.2-82, GOST 9717.2-83;

copper-zinc alloys - GOST 9716.0-79, GOST 9716.1-79, GOST 9716.2-79, GOST 9716.3-79;

tinless bronzes - GOST 20068.0-79, GOST 20068.1-79, GOST 20068.2-79, GOST 20068.3-79.

X-ray spectral analysis. Compared to optical spectra, X-ray characteristic spectra contain fewer lines, which simplifies their interpretation. This advantage is driving the increasing use of X-ray analysis in factory laboratories.

The characteristic X-ray spectrum of the sample can be obtained either by placing it on the anode of the X-ray tube and irradiating it with an electron beam with an energy of 3-50 keV (emission method), or by placing the sample outside the tube and irradiating it with sufficiently hard X-rays emanating from the tube (fluorescence method).

The fluorescent method is preferable because:

has a higher sensitivity (up to 0.0005%);

more efficient and technologically advanced (there is no need to make the tube collapsible and pump it out to maintain a vacuum);

the sample is not heated.

Fluorescent X-ray spectrometers (Spark-1-2M, Lab-X3000, ED 2000, MDX 1000) used in industry to control the chemical composition of steels and alloys are equipped with a computer, which makes it possible to automate the processing of spectra and increase efficiency (Fig. 3.4).

The results of the control of the chemical composition of the metal are drawn up in the accompanying documentation and registered in the passport of the incoming control.

Rice. 3.3. Optical scheme of the steeloscope: 1 - light source (electric arc between the electrodes, which are the samples under study); 2 - capacitor; 3 - slit; 4 - rotary prism; 5 - lens; 6 and 7 - prisms that decompose light into a spectrum; 8 - eyepiece

Rice. 3.4. Functional diagram of a fluorescent X-ray spectrometer: RT - X-ray tube; A - analyzer; D - detector

During the incoming inspection of imported materials, the grade of the material is determined in accordance with the certificate for chemical composition.

Control of mechanical properties. This type of control is carried out in the CPL in accordance with the requirements of the STP and TI. The content and scope of control of the mechanical properties of the metal products supplied to the enterprise is determined by the metal grade, delivery status and purpose in accordance with NTD.

As a rule, mechanical properties are controlled by tests: uniaxial tension, hardness, impact strength (see Ch. 2). The shape and dimensions of test specimens must comply with the requirements of GOST 1497-84 and GOST 9454-78.

For tensile tests of metal of round, square and hexagonal cross-section, 2 samples are taken from each batch, 60 mm long from either end of the rolled stock.

For tensile tests of wire supplied in coils for the manufacture of springs, a sample with a length of 600 mm is taken from one coil of each batch, and for wire with a diameter 0.9 mm one sample 1500 mm long at a distance of at least 1 m from the end of the bay.

For tensile tests of rolled sheets, two samples of 250 mm long and 50 mm wide are taken from one sheet along the rolling direction, and from sheets of aluminum and magnesium alloys - across rolling. For tapes and strips from one roll of each batch, a sample of 400 mm in length is taken at a distance of at least 1 m from the end of the roll.

To test for impact strength from sheets, strips with a thickness of at least 11 mm, from pipes with a wall thickness of at least 14 mm, rods with a diameter of at least 16 mm from either end next to the sample for tensile tests, take 2 samples of size 11 × 11× 60 mm for making samples of size 10 × 10× 55 mm. 2 samples are taken from rolled products with a thickness of up to 10 mm to make samples of size 5 × 10× 55 mm. For testing for impact strength at subzero temperatures, 3 samples are taken.

If results are obtained that do not correspond to the certificate, the test is repeated on twice the number of samples. If, during repeated tests, negative results are obtained on at least one sample, then the entire batch of metal is rejected. The results of the mechanical properties of the metal are reflected in the passport of the incoming inspection with the attachment of test tables.

Conclusion

In the conditions of the global market, into which the Russian economy is being integrated, enterprises need management that provides advantages over competitors in terms of quality criteria. Gradually comes the understanding that the presence of a technical control department is no longer enough to produce products of the required quality.

An increasing number of enterprises, in order to increase their competitiveness, are aware of the need to create a quality management system and carry out its certification for compliance with the requirements of international standards.

Having studied the topic "Quality management", we found out that the direct management of the quality management system is carried out by the authorized representative, that his duties include:

ensuring the development, implementation and maintenance of the quality management system;

control over the conduct of internal audits of the quality management system, analysis of its effectiveness;

presentation of reports to the director on the functioning of the quality management system, analysis of its effectiveness.

We also found out that the operational activities related to the functioning of the quality management system are carried out by a specially created quality service, whose tasks include:

coordination of work and direct participation in the development, implementation and operation of the quality management system;

creation of a database on the quality management system;

organization of accounting and control over the implementation of measures and documents of the quality management system, conducting internal audits;

improvement of the quality management system.

In accordance with the new requirements, the organization must establish and detail requirements for the measurement of products / services, including acceptance criteria. Measurements should be planned in order to confirm their compliance with the detailed requirements. The organization should plan to use statistical methods to analyze the data. When analyzing problems, the causes should be identified before planning corrective or preventive action. Information and data from all parts of the organization should be integrated and analyzed to assess the overall status of work in the organization. On the basis of objective information, methods and means for continuous improvement of processes are determined.

The effective functioning of the quality system presupposes the creation and operation of an information retrieval system, corrective actions and the results obtained in the field of quality.

The presence of a certified quality system at the enterprise is not an end in itself. First, a number of industries have their own specific certification systems. Secondly, ISO 9000 certification is a necessary but insufficient element of competitiveness. And thirdly, the recognized leaders of the market economy create their own, more developed and perfect quality management systems. But, undoubtedly, the absence of an appropriate quality system deprives enterprises of the prospects for surviving in conditions of fierce competition.

List of used literature

1. Rebrin Yu.I. Quality Management: A Study Guide. Taganrog: Publishing house of TRTU, 2004.174s.

Great Soviet Library, TSB; # "justify">. Gludkin O.P. Methods and devices for testing RES and EMU. - M .: Higher. School., 2001 - 335 p.

Unofficial site of GOSTs; # "justify">. Stroy Consultant; # "justify">. A.I. Orlov Mathematics of Chance: Probability and Statistics - Basic Facts: A Study Guide. M .: MZ-Press, 2004, - 110 p.

V.G. Shipsha. Lecture: Incoming quality control of metal products.

Types of quality control

Solid

Selective

Incoming control

Interoperational control

More accurate classification

Quality Management System Certification

Certification- a procedure that confirms the conformity of a product, process or service to the specified requirements by a third party and formalized in the form of a written guarantee.

The quality management system in the ISO 9000 standards is understood as a part of the enterprise management system based on documented procedures for the management and implementation of business processes.

ISO 9000 is a series of international standards for establishing a quality management system.

Certification of quality management systems is a highly effective market tool, as a certificate issued by a reputable organization is recognized as tangible evidence of quality that the consumer (customer) can expect.

The formulation of modern quality management assumes that the enterprise must undergo a systemic restructuring of activities affecting tasks that to one degree or another rely on the quality management principles laid down in the ISO 9000 series (strategy, structure, processes, personnel).

The certification procedure aims to give the manufacturer of the relevant products a license to use the conformity mark.

In Russia, in accordance with the Law on Certification of Products and Services, a state product certification system has been created, which operates "under the guidance of Gosstandart of Russia as a national certification body. The national standard describing the QMS certification procedure is GOST R 40.003. This system complies with ISO rules.

The basis for certification on indicators of ensuring human safety and environmental protection are domestic or foreign standards.

The presence of a certified system allows an enterprise to:

1.Reduce non-productive costs (production losses);

2. to improve the level of quality of products or services;

3. to be more competitive;

4. to improve the organizational structure of management and increase its efficiency;

5. to increase the volume of sales of products;

6. sell manufactured products on the international market;

7. the possibility of obtaining preferential loans;

8. to receive a state, municipal, or city order for the production of works and services;

9. to form public opinion about the stable position of the enterprise in the market.

Question 28. Fixed assets: concept, composition, structure. Fixed production and non-production assets. Depreciation and reproduction of fixed assets. Depreciation and methods of its calculation.

Fixed assets - these are material values (means of labor) that repeatedly participate in the production process, do not change their natural material form and transfer their value to finished products in parts as they wear out.

Classification of fixed assets.

1. By purpose and scope:

Basic production assets;

Fixed non-production assets.

2. By the degree of use:

Fixed assets in operation;

Fixed assets in reserve;

At the stage of completion, reconstruction, partial liquidation;

Mothballed.

3. Depending on the existing rights to property:

Objects belonging to the enterprise on the basis of property rights;

Objects under operational management or economic management;

Objects received for rent.

4. By natural-material composition:

Structures;

Transfer devices;

Cars and equipment;

Vehicles;

Tools, production and household inventory

According to the degree of participation in the production process, fixed assets are divided into active and passive. The active part (machinery, equipment) directly affects the production, quantity and quality of products (services). Passive elements (buildings, structures, transport) create the necessary conditions for the production process.

Types of quality control

Thus, a distinction is made between sample, solid and statistical types. Solid all products are inspected. With a complete control in production, a record of all defects arising in the process of manufacturing a product is kept.

The process of product quality control at enterprises is carried out by the technical control department (QCD) or the quality control department.

More accurate classification

Factors affecting product quality

At each enterprise, various factors, both internal and external, affect the quality of products.

Internal include those that are associated with the ability of the enterprise to produce products of appropriate quality, i.e. depend on the activities of the enterprise itself. They are numerous, they are classified into the following groups: technical, organizational, economic, social and psychological.

Technical factors have a significant impact on the quality of products, therefore, the introduction of new technology, the use of new materials, higher quality raw materials are the material basis for the production of competitive products.

Organizational factors are associated with improving the organization of production and labor, increasing production discipline and responsibility for product quality, ensuring the culture of production and the appropriate level of qualifications of personnel.

Economic factors are due to the costs of production and sale of products, pricing policy and the system of economic incentives for personnel for the production of high-quality products.

Socio - economic factors significantly affect the creation of healthy working conditions, loyalty and pride in the brand of your company, moral incentives for employees - all these are important components for the production of competitive products.

External factors in market conditions contribute to the formation of product quality. The external or environment is an essential condition for the existence of any enterprise and is an uncontrollable factor in relation to it. All the impact of the external environment can be divided into the following individual factors: economic, political, market, technological, competitive, international and social.

Environmental analysis enables an organization to predict its capabilities, to plan for contingencies, to develop an early warning system for potential threats, and to develop strategies that could turn external threats into any profitable opportunity. An analysis of the external environment is necessary in the process of strategic planning.

Competitive factors occupy a special place among the considered factors of the external environment. No organization can afford to ignore the actual or possible reactions of its competitors.

In the conditions of market relations, the goals of the enterprise are changing, which combine the following issues: ensuring survival, maximizing workload, maximizing current profits, gaining leadership in a market segment, gaining leadership in terms of product quality, achieving a specific sales volume, increasing sales, gaining customer loyalty.

The fourth stage is to analyze and evaluate information. This allows you to determine the presence and degree of deviations from the specified parameters and the need for corrective actions.

The third stage of the control process is to obtain information about the state and results of the functioning of its object, allowing you to make informed decisions about how to proceed.

At the second stage, a model of the organization is created, which reflects the flows of resources, information, cost centers, the formation of intermediate and final results, which are most suitable for observation.

By subjects that carry out the control process (administration, functional services, special units, employees themselves).

By types (financial, production, quality control, etc.).

3. By objects, which are:

The state of production, technical, personnel potential, the amount of financial resources, inventories;

-efficiency of production activities;

- intermediate and final results, etc.

5.By intensity(normal or enhanced).

6.According to the place of implementation(volatile, stationary).

7.On goals(filtering, corrective).

8.By methods:

-actual

-documentary

- evaluative.

9. By stages of implementation: preliminary, current, final.

Preliminary control is carried out before the start of work. Its main means is the implementation of certain rules, procedures, lines of behavior, the observance of which allows you to develop in a given direction.

Current (operational) control is carried out in the course of work and allows you to exclude any deviations from the planned plans and instructions, which does not allow these deviations to develop.

Feedback is required for control, i.e. data on the results obtained.

Final (final) control is carried out after completion of work.

It serves two important functions:

1.Gives information for planning(if similar work will be carried out in the future).

2.Promotes motivation(i.e. provides fair remuneration).

Control is an activity to regulate relations in an organization, focused on creating favorable conditions for the preparation and implementation of management decisions.

Each of the selected types of control is aimed at a specific object for itself, which serves as the main base for their identification.

To carry out the control procedure, it is necessary to consistently overcome its four stages.(fig. 5):

Rice. 5. Stages of the control process.

At the first stage, the parameters of the functioning and development of the organization, which need to be monitored, and the sources of information about them are determined. These parameters are in the form of various standards and norms, reflecting the tasks laid down in the plans.

The control process is a diachronous process and covers in time both the initial stage of management and its final part. And if the diagnostic and orienting control functions fall mainly on the input blocks of the information-cybernetic control model, then the stimulating and corrective functions fall on the weekend. The coordination of control over time is the most important generic characteristic of controlling activity, which makes it relevant to divide it into preliminary, current and final stages, which fall into two key forms within the information-cybernetic model: input and output control.

Input control is designed to carry out the functions of monitoring and regulating information flows entering the control apparatus. The content of these flows should include information about the material, financial and energy sources of the organization's activities, about their staffing. At the entrance, the supervisory authorities must ensure that all tasks arising from the strategic planning scheme are correctly distributed, so that each member of the organization clearly understands what he must do, what is his responsibility for the violations committed. Incoming control is also necessary to assess the state of the production system and its vulnerabilities - a kind of channels for the possible destruction of the system.

The object of incoming control is the flows entering the production system of the enterprise, which serve as the initial condition for the activity of this enterprise. The list of these streams should include:

-material (equipment, raw materials, resources);

-technological (patents, know-how, etc.);

-frame;

-informational;

-Financial, etc.

The most important condition preceding the control procedure is communicating the current goals of the organization to the performers... For this, the controlling entity must necessarily know what should be the result and how best to implement it. Control shouldn't inspire fear and therefore, the purpose of control will not be a prohibition or threats, but the maintenance of an optimal regime in the work of subordinates. Control should be more of a warning than a finding.

There are two types of incoming control: direct and indirect.

Direct control Is an input management activity attributed to a state manager in accordance with his job description... Direct control is divided into two subspecies: tight executive control, the object of which is the activity of the performer itself, and soft functional control, involving tracking mainly the results of activities, and not by the form of the performer's activity.

Factors formed at the intersection of two conventional axes: the goal and the means to achieve it, may fall under the direct control. The axis of the goal is usually made up of such objects of incoming control as hiring employees, determining the scope of work, the quality and timing of tasks performed, etc.. On the axis of funds, you can postpone such indicators as the personal qualities of those who are hired or receive assignments, the conditions of work, the nature of personnel training. etc. The calculation of the optimal combinations between the set control objectives and the means available for this will allow the manager to evenly distribute among the controllers the sphere of their direct responsibility for achieving the goals. The scoring of the calculation will help to identify the priorities in the assessment of a particular level in order to choose the optimal tactics in the implementation of the control goal.

Indirect control- activities to control input flows based on the indirect authority of the manager. Indirect control is divided into two types : control through related indicators and self-control.

Control through related indicators is based on the allocation of such control standards (standards), the value of which is objectively related to each other . Thus, by controlling the level of costs at the enterprise, an official cannot but control the level of profit. We have to admit that the list of standards that set control zones at an enterprise determines the overlap of these zones, which can lead to a loss of clarity in the distribution of control areas.

Self-control expresses the highest degree of trust between the manager and the subordinate, especially in cases where direct methods of control are impossible, or where there is a long distance between the executive and regulatory authorities. . The truncated tram line "Conscience is the best controller" is a good illustration of this kind of control. Currently, the share of self-control is growing rapidly. This is due to the increasing complexity of the production and marketing system.

Incoming quality control is designed for basic and auxiliary materials: paper, paint, dampening solution, blanket.

The main stages of paper quality control are to determine the compliance of the printing and technical properties of the paper with the values of the standards. The first stage is visual inspection. When examining the foot, one should pay attention to the integrity of the package, and when opening it, to the presence of folds and wrinkles, waviness and dirtiness. The next stage is measuring the moisture content of the paper. The moisture content of the paper is measured using moisture meters, while it should be in the range of 5-7%. The last step is to determine the whiteness of the paper. Whiteness control is carried out using a densitometer. For lightweight paper (with a weight of 60 g / m 2), the opacity index is important, because such paper requires a more careful approach to the choice of ink in order to avoid such a common defect as the translucent image from the back. The method for determining the transparency of the paper Ї inspection of the paper for transmission or with the help of densitometers.

The quality of printed matter, along with the properties of paper, is also influenced by the properties of inks. The main indicators are viscosity, thixotropy and grinding degree. To assess the viscosity of offset inks, rod viscometers are used, the measured values must correspond to the indicators provided by the manufacturer. To assess thixotropy, visual control is used (mix the paint and watch how long it took the paint and binder particles to form a dense structure). To assess the degree of grinding of offset inks, the Klin device is used.

To adjust the properties of paints, various additives are used that adjust the drying rate of paints and the performance properties of their films on the print. Various oils are also used to prevent drying out.

To assess the quality of the dampening solution, such indicators as acidity, electrical conductivity and hardness of the water used are used. Acidity ( NS) a dampening solution is one of the most important indicators. Optimal values pH ranges from 4.8-5.5. Important to remember, pH solution must match pH paper, otherwise a defect (yellow spots on paper) may form as a result of printing. The conductivity of the dampening solution is an indicator that characterizes the content of salts and various additives in the dampening solution. The electrical conductivity of tap water usually ranges from 300 to 500 μS. The operating conductivity of the dampening solution should be between 800 and 1500 μS. The optimal value of water hardness when preparing a dampening solution is 250.25-600.6 ppm. Even small deviations from these values can cause printing problems.

The control of blankets is carried out by measuring the Shore hardness. If necessary, the stiffness is adjusted by placing a calibrated cardboard under the blanket.

Output control

The quality of production prints is controlled using control elements (alignment crosses) and scales located on the sheet.

The alignment quality is assessed visually using a magnifying glass. The control of the supply and the uniformity of the supply of paint and moisture is carried out by dies, it can be visual and using a densitometer. Control of the balance of the paint-dampening solution is carried out visually on the dies and raster elements of each color.

Deformation control of raster elements (dot gain) is performed visually for each paint by comparing a dotted raster 50% field with a line field.

Color balance control "by gray" is performed visually in 3 fields: light, partial shade and shadow. In a quality print, the control is neutral gray.

Slip and crushing control is carried out visually. Print slip controls consist of a set of straight or concentric lines. Since any slip is the creation of a second identical image, the superposition of two periodic structures with a linear or angular displacement will result in a moiré appearance.

Quality control of reproduction of small elements in highlights and shadows is carried out by means of fields having a point with a relative area of 1, 3, 5 and 95, 97, 99%. I use a magnifying glass for control.