Incoming control of raw materials and organoleptic (sensory) method of qualitative assessment of raw materials. Modern problems of science and education

INPUT CONTROL OF PRODUCTS

BASIC POINTS

GOST 24297-87

PUBLISHING HOUSE OF STANDARDS

Moscow

STATE STANDARD OF THE USSR UNION

Date of introduction 01.01.88

This standard establishes the basic provisions for the organization, conduct and registration of the results of incoming inspection of raw materials, materials, semi-finished products and components (hereinafter referred to as products) used for the development, production, operation and repair of industrial products.

1. GENERAL PROVISIONS

1.12. The decision to tighten, weaken or cancel incoming control is made by the consumer in agreement with the State Acceptance and the customer’s representative office based on the results of incoming control for the previous period or the results of operation (consumption) of the product.

2. ORGANIZATION OF INPUT CONTROL

2.1. Incoming inspection is carried out by the incoming inspection unit, which is part of the technical control service of the enterprise (association).

2.2. The main tasks of incoming control are:

1) checking the availability of accompanying documentation for the products, certifying the quality and completeness of the products;

2) control of compliance of the quality and completeness of products with the requirements of design and regulatory technical documentation and its application in accordance with permit protocols;

3) accumulation of statistical data on the actual level of quality of the resulting products and development on this basis of proposals to improve the quality and, if necessary, revise the requirements of the technical documentation for products;

4) periodic monitoring of compliance with the rules and shelf life of suppliers’ products.

Workplaces and personnel performing entry control must be certified in the prescribed manner.

Measuring instruments and testing equipment used during incoming inspection are selected in accordance with the requirements of the normative and technical documentation for controlled products and GOST 8.002-86. If metrological means and control methods differ from those specified in the technical documentation, then the consumer agrees on the technical characteristics of the means and control methods used with the supplier, State Acceptance and (or) with the customer’s representative office.

To carry out tests, inspections and analyzes related to incoming inspection, products can be transferred to other divisions of the enterprise (laboratories, control and testing stations, etc.).

3. PROCEDURE FOR CONDUCTING INPUT CONTROL

3.1. Products accepted by the quality control department, the customer's representative office, the State acceptance of the supplier enterprise and received with accompanying documentation drawn up in the prescribed manner are allowed for incoming inspection.

3.2. When conducting incoming inspection it is necessary:

1) check the accompanying documents certifying the quality of the products and register the products in the journals for recording the results of incoming inspection ();

2) control the selection of samples or samples by warehouse workers, check the completeness, packaging, labeling, appearance and fill out the sampling or sampling report;

3) carry out quality control of products according to the technological process of incoming control or transfer samples or samples to the appropriate department for testing (analysis).

3.3. The department that received samples or samples for testing (analysis) conducts tests within the established time frame and issues a conclusion to the incoming control department about the compliance of the tested samples or samples with the established requirements.

3.4. The results of tests or analyzes (physical and mechanical properties, chemical composition, structure, etc.) must be transferred to production along with the tested products.

3.5. Products accepted based on the results of incoming inspection must be transferred to production with the appropriate mark in the accounting or accompanying documents.

Marking (stamping) of accepted products is allowed.

3.6. Products received from the supplier before incoming inspection must be stored separately from those accepted and rejected by incoming inspection.

3.7. Products rejected during incoming inspection must be marked “Defective” and sent to a defective isolator.

4. REGISTRATION OF INPUT CONTROL RESULTS

4.1. Based on the results of the incoming inspection, they draw up a conclusion on the product’s compliance with the established requirements and fill out a logbook for recording the results of the incoming inspection.

4.2. In the accompanying documents for the products, a note is made about the incoming inspection and its results, and the products are marked (branded), if this is provided for in the list of products subject to incoming inspection.

4.3. If the product meets the established requirements, the incoming control department makes a decision to transfer it to production.

If non-compliance with the established requirements is detected during the incoming inspection, the products are rejected and returned to the supplier with a complaint.

If you repeatedly receive low-quality products or receive them in large quantities, the consumer reports this to the territorial body of the Prosecutor's Office at the location of the supplier.

4.4. Based on the results of the incoming inspection, the consumer, if necessary, informs the supplier’s ministry, the customer’s representative office and (or) the State Acceptance Authority at the supplier enterprise about the non-compliance of the products with the established requirements, and in the absence of the latter - the territorial body of Gosstandart at the location of the supplier to take measures in accordance with those assigned to them functions ().

4.5. For electrical radio products accepted by the customer's representative office, information is sent to the customer's head institute for these products ().

departmental subordination of the enterprise

INTELLIGENCE

on the supply of raw materials, materials, semi-finished products and components in violation of the requirements of scientific and technical documentation (TU standards) for the period from _______________________ to ___________________

Note. If materials and components are accepted by the State Acceptance Office or the customer’s representative office, this is indicated in the note.

APPENDIX 3

mandatory

Information submission form

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the USSR State Committee for Standards

DEVELOPERS

M. G. Iofin(topic leader); L. V. Ermilova(topic leader); Y. G. Ostapchuk, Ph.D. tech. sciences; A. A. Bogatyrev, Ph.D. economy sciences; I. I. Chaika, Ph.D. economy sciences; S. G. Atamas; S. A. Afonin; Yu. F. Afanasyeva; K. V. Lebedev, Ph.D. Tech. sciences; Yu. S. Vartanyan, Ph.D. tech. Sci.

2. APPROVED AND ENTERED INTO EFFECT by Resolution of the USSR State Committee for Standards dated 06/04/87 No. 1809.

3. INSTEAD GOST 24297-80

4. REFERENCE REGULATIVE AND TECHNICAL DOCUMENTS

5. Reissue. April 1993

Under incoming quality control refers to the control of supplier products received by the consumer and intended for use in the manufacture, repair or operation of products. Its main goal is to exclude the possibility of penetration into production of raw materials, materials, semi-finished products, components, tools with deviations from the quality parameters provided for by regulatory documentation.

When conducting incoming inspection, plans and procedures for conducting statistical acceptance control of product quality according to an alternative criterion are used.

Control plan- this is a set of values of sample volumes, acceptance and rejection numbers.

Control by alternative characteristics- this is a quality control, during which each tested unit of product is classified as suitable or defective, and the subsequent decision on the controlled population is made depending on the defective units of product found in the sample or sample or on the number of defects per certain number of units products.

Acceptance number- this is a control standard that is a criterion for acceptance of a batch of products. It may be equal to the maximum number of defective units in a sample or sample.

Rejection number- this is a control standard that is a criterion for rejecting a batch of products. It may be equal to the minimum number of defective units in a sample or sample.

Unit of production- a separate copy of piece products or a quantity of non-piece or piece products determined in accordance with the established procedure.

Defective item- a unit of product that has at least one defect.

At random control the incoming inspection plan must comply with the acceptance testing control plan established in the standards and specifications.

Complete control is carried out in the absence of data on the actual defectiveness of the product, with increased requirements for it on the basis of technological processes and STP developed by technological services, agreed with the quality control department and approved by the head of the enterprise.

Topic 6. Seven quality control tools.

6.1. General information.

One of the principles of total quality management is that decisions should be based only on facts and not intuition. The issues of collecting, processing and analyzing the results of measuring quality indicators are dealt with by mathematical statistics, which includes a huge number of different methods developed to date. Many of the modern statistical methods are quite difficult to understand, much less to be widely used by all participants in the process.

As a result of practical experience in product quality control, seven main ones were selected from a variety of methods:

check sheet;

bar chart;

scatter plot;

stratification method (data stratification);

Pareto chart;

cause-and-effect diagram (Ishikawa diagram);

control cards.

These methods can be understood and used without special mathematical training. Despite their simplicity, they allow you to maintain a connection with statistics and enable professionals to use the results of these methods and, if necessary, improve them. The sequence of application of the seven methods may be different depending on the goal set for the quality system.

Statistical methods are the tool that needs to be learned to implement quality management. They are the most important component of a comprehensive total quality management control system. Their main purpose is to control the ongoing process and provide the process participant with facts for adjusting and improving the process. The use of statistical methods is a very important way to develop new technologies and control the quality of processes.

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NON-STATE EDUCATIONAL INSTITUTION OF HIGHER PROFESSIONAL EDUCATION

"YELABUGA CITY INSTITUTE OF INNOVATIVE TECHNOLOGIES"

Faculty of Engineering and Technology

Department of Quality Management

Test

in the discipline: “Means and methods of quality management”

on the topic: “Incoming product quality control”

Yelabuga 2011

Introduction

2. Incoming product quality control, 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. This is also the most comprehensive function in terms of the methods used, which are the subject of a large number of works in different fields of knowledge. The importance of control lies in the fact that it allows you to identify errors in time, so that you can 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, organization of incoming control and efficiency.

The test consists of an introduction, 4 chapters, a conclusion, where all the conclusions of the work and a list of references are summed up.

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

quality control standard metal products

1. Concept and types of product quality control

Quality control means checking the compliance of the quantitative or qualitative characteristics of a product or process on which the quality of the product depends with established technical requirements.

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

The essence of product quality control at an enterprise is to obtain information about the condition of the object and compare the results obtained with the established requirements recorded in 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 operational maintenance, ensuring in case of deviation from regulated quality requirements, taking corrective measures aimed at producing products of adequate quality, proper maintenance during operation and full satisfaction of consumer 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 deviations from the norm of the required level of quality can be corrected even before defective products or products that do not meet technical requirements are released. Insufficient control at the stage of manufacturing 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 arriving at the enterprise’s warehouses;

* production-by-operation control over compliance with the established technological regime, and sometimes inter-operational acceptance of products;

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

* control of models and prototypes;

* control of finished products (parts, small assembly units, subassemblies, assemblies, blocks, products).

2. Incoming product quality control, definition, concept

purpose, main tasks, organization of incoming control,

efficiency

Incoming product quality control should be understood as quality control 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 organizing, conducting and processing the results of incoming inspection of raw materials, materials, semi-finished products, components, etc., coming from suppliers to consumers.

The recommendations were developed to provide methodological and practical assistance to enterprise specialists in the implementation and use of a product quality management system based on the application of international standards 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 unambiguous mutual recognition of the results of product quality assessment by the supplier and the consumer, carried out using the same methods and the same control plans;

establishing compliance of product quality with established requirements in order to timely submit claims to suppliers, as well as to promptly work with suppliers to ensure the required level of product quality;

preventing the launch into production or repair of products that do not meet established requirements, as well as permitting 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 consumer organization and intended for use in the manufacture, repair or operation of products, as well as the provision of services. Its main goal 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 contractual obligations. Imperfections in this type of control can bring significant losses to both the product manufacturer and its consumer.

Incoming control is very labor-intensive and expensive, and it duplicates the output control of the manufacturing enterprise. In this regard, it is becoming increasingly important to abandon incoming control by strengthening output control, which entails the establishment of special relationships with the supplier. The practice of such relations has existed abroad for a long time. For example, at the Japanese company Bridgestone Corporation, supplied parts and raw materials are inspected mainly to check their quantity and compliance with technical documentation. The quality of materials is not checked, as it is carried out by suppliers before sending them 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. To implement it at industrial enterprises, specialized units are created in the quality control system. Medium and large enterprises operate incoming control laboratories. The main tasks of these units are:

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

Preparation of documents based on control results;

Control of technological tests (samples, analyses) of incoming resources in workshops, laboratories, control and testing stations;

Monitoring compliance by warehouse workers with the rules for storing and releasing incoming products into production;

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

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 100% control and testing of the supplied material and technical resources or services;

Selective acceptance testing of a batch of goods by the supplier and consumer simultaneously;

The supplier's use of a formal quality assurance system defined by the customer (for example, 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 “Manufacture of products” in subsection 7.4 “Purchases”, paragraph 7.4.1 states: “The organization must ensure that purchased products comply with established procurement requirements. The scope and nature of control over the supplier and purchased products should be determined by the degree of influence of these products on subsequent production of the product or on the finished product.”

The organization shall evaluate and select suppliers based on their ability to provide products in accordance with the Organization's requirements.

Criteria for selecting, evaluating and re-evaluating suppliers must be established. Records should be kept of the results of this assessment and subsequent actions.”

In clause 7.4.2 “Purchasing Information” we read: “Purchasing information must contain a description of the products being ordered and include, where necessary:

Requirements for approval of products, procedures, processes and equipment;

Requirements for personnel qualifications;

Requirements for the quality management system.

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

And finally, paragraph 7.4.3 “Checking (verification) of purchased products is as follows: “The organization must determine and implement control measures or other activities necessary to ensure compliance of purchased products with the requirements specified in the procurement information. In cases where the Organization or its consumer intends to check (verify) purchased products at the supplier’s enterprise, the Organization must establish in the procurement information the intended measures for such verification and the method of product release.”

3. Incoming quality control of metal products

The main indicators of metal quality 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 specified in national standards, technical specifications of companies (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 production chain. The quality of metal products entering the enterprise is determined during incoming inspection (IC).

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

Organization of incoming quality control of metal products:

In accordance with GOST 24297-87, incoming inspection is carried out by an incoming inspection unit - the incoming inspection bureau (IBK), which is part of the enterprise's technical quality control service (QC).

The main tasks of incoming control are:

monitoring the availability of accompanying documentation for products;

control of compliance of the quality and completeness of products with the requirements of design and regulatory technical documentation;

accumulation of statistical data on the actual level of quality of the resulting products and development on this basis of proposals to improve the quality and, if necessary, revise the requirements of the technical documentation for products;

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

Incoming inspection 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 occupational safety requirements. Measuring instruments and testing equipment used during incoming inspection are selected in accordance with the requirements of the normative and technical documentation for controlled products and GOST 8.002-86. If metrological means and control methods differ from those specified in the technical documentation, then the consumer agrees on the technical characteristics of the means used and control methods with the supplier.

To ensure compliance with the requirements of GOST 24297, as well as the standards of the GOST R ISO 9000 series, the enterprise is developing its own technical documentation, taking into account the profile and characteristics of the products. For example, large enterprises are developing 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 recording 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 inspection. The scope and types of incoming inspection are established in accordance with the normative and technical documentation and technical specifications for manufactured products.

Conducting the VC is entrusted to the BVK. Input control involves: a warehouse for purchased metal products or a consumer workshop (hereinafter referred to as the warehouse) and the central factory laboratory (CPL).

Incoming inspection of metal products includes the following checks:

accompanying documentation certifying quality (certificate, passport);

labeling, containers, packaging;

geometric dimensions;

surface conditions;

special properties;

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

A typical scheme for organizing a VC (Fig. 3.1) is as follows. Metal products received at the warehouse are accepted with accompanying documentation on nomenclature, assortment and quantity and no later than 10 days are transferred for incoming control. At the incoming inspection, 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 control of the BVK. Selected samples are transferred to the Central Laboratory. Based on the incoming inspection data, including the conclusions of the central laboratory, a conclusion is made about the compliance of the quality of metal products with the established requirements.

Rice. 3.1. Typical scheme for organizing incoming control

If the inspection results are positive, the accompanying documentation (certificate, passport) is marked “Incoming inspection completed, complies with technical specifications”

If any indicator does not meet the established requirements, twice the 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 report.

Rejected metal is marked with red “Reject” paint and stored in a reject isolator until a decision is made on disposal or return.

Control of geometric dimensions. The TI regulates the scope of control over the size of the assortment of metal products, which is, as a rule, 5% of one batch. Dimensions are controlled using measuring instruments that provide a measurement error equal to? tolerance on the measured parameter.

Depending on the type of assortment (rod, strip, sheet, etc.), the dimensions specified in the certificate are subject to control, while the technical specifications stipulate how and in what places measurements are taken.

For example, the thickness of strips and tapes should be measured 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.

The thickness of sheets and plates is measured at a distance of at least 115 mm from the corners and at least 25 mm from the edges of the sheet using a caliper (GOST 166-89).

The diameters of rods and wires are measured in at least two places in two mutually perpendicular directions of the same section using a micrometer (wire) or a caliper (rod). Width and length are measured with a metal tape measure 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 normative and technical documentation for delivery visually without the use of magnifying devices (except for cases specifically stated). The recommended amount of inspection is 5% of the lot. In some cases (forgings, castings, etc.), 100% of the product is subjected to surface control.

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

Table 3.1 Surface defects of metal products

Name of defect	Types, origin and brief description of the defect	The influence of a defect on the quality of a semi-finished product or finished product
Metallurgical defects
Captivity (Fig. 3.2, a)	During pressure treatment, the walls of the bubbles and cavities of the ingots are compressed, stretched and partially widened. As the compression of the metal increases, the outer walls of the chambers become thin and break through. The delamination of metal thus formed, more or less parallel to the surface and extending onto it, is called a film	Removing film on semi-finished products, if their depth does not exceed the dimensional tolerances, does not affect the quality of the product. Films on the surface of the tubes lead to product rejection
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 hardening, burns during grinding and similar reasons.	Cracks that do not take the semi-finished product beyond the dimensional tolerances are classified as repairable defects. Cracks in the finished product 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
Sinks	Holes on the surface of castings are the result of unsatisfactory molding, cutting out defects, and in products obtained by pressure processing, a consequence of opened bubbles, etc.	If the shell does not take the size of the product beyond the established tolerances, semi-finished products with surface shells are considered a correctable defect. In finished products, shells lead to rejection
Burrs and sunsets	A burr is a convexity along a rolled profile resulting from the extrusion of metal from a stream into the gap between the rolls. A burr is a burr rolled into metal during finishing rolling. Burrs are also found on stamped workpieces when the halves of the trimming die are displaced	Finished rods and rods of profile metal in the presence of a burr or decline are rejected
Ringiness	Ringiness - herringbone-like dents and marks on the tubes, sometimes easily palpable by hand, are a consequence of the high friction force arising during the drawing process, accompanied by strong vibration	Ringiness on finished tubes leads to their rejection
White spots and stripes	White spots and stripes are defects found mainly on aluminum products. They are a consequence of metal contamination with electrolyte, the presence of non-metallic inclusions and sodium and calcium impurities	The defect sharply reduces the corrosion resistance of aluminum and aluminum products, and also spoils their appearance
sodium sickness	Sodium disease - inclusions of sodium compounds in aluminum	The defect renders aluminum products defective
	Ripples are dotted impressions of indentation on the surface of aluminum products caused by aluminum sticking to the rolling rolls.
Chemical defects
Overtrawl	Overetch is characterized by a rough surface, revealing the crystalline structure of the metal. Severe overetching in thin-walled products leads to a significant reduction in the cross-section of the walls. Over-etching is a consequence of the high concentration of etching substances, as well as the long exposure of products in them
Poor grass	Undergrasses are dark spots or uneven shade of the surface. Under-etching is a consequence of etching with solutions of weak acids and alkalis or exhaustion of the bath, short exposure in the bath, as well as contact of products with each other during etching
Matte	It is the result of uneven etching caused by oil contamination during stamping, segregation heterogeneity, etc.
Rough spots	Rough dark and white spots on light metal products indicate corrosion
Mechanical defects
Risks and challenges	Risks (longitudinal scratches) arise on the internal and external surfaces as a result of poor polishing of the dies, the ingress of solid particles (sand, scale, metal shavings), the ingress of the same particles into the drawing point during broaching, with unsmooth surfaces of profiles, dies, etc. n. Seizures are obtained as a result of pressing at high temperatures or at high pressing speeds	Defects spoil the appearance, reduce the dimensional accuracy of manufactured products, and sometimes lead to defects
Flaws and tears	Fractures and tears are the result of metal rigidity, defects in the stamping tool (sharp corners) and improper installation of dies	Leads to product failure
Wrinkles and folds	They are most often found on the bodies of drawn products and represent vertically located thickenings caused by metal compression. These defects result from uneven thickness of the workpiece or clearance between dies and insufficient preheating of the workpiece	They spoil the appearance and lead to defective finished products.
Chernoviny	Unpolished areas of products with scale remaining at the bottom	The defect contributes to rapid wear of the product, spoils the appearance and interferes with work with a certain accuracy
	Recesses obtained during processing with an abrasive tool	They shorten the service life of the product and spoil the appearance of the surface. Snatches on the cutting part of the tool reduce the quality of its work
Grooves	Grooves are lines visible to the naked eye and running in the direction of rough grinding on finished products (tools)	Grooves spoil the appearance, reduce corrosion resistance, and in some devices and tools affect proper operation
Peeling of metallic or non-metallic coatings	Peeling of metallic and non-metallic coatings is the result of poor adhesion to the base metal
Nicks (Fig. 3.2, d)

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

If it is necessary to control the inner surface of pipes, samples are cut from them, cut along the generatrix and the presence of defects is checked. In all cases, when defects are detected (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 the depth of its occurrence. Based on 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 central laboratory on specially selected samples from each batch of metal with a conclusion drawn up in the prescribed form.

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

The sampling rate for monitoring the chemical composition is established in the technical specifications and is usually:

for sheets and slabs - from one control sheet, batch slab;

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

for rods and profiles that are individually stamped by the supplier - from one rod, profile, batch;

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

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

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

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

For express and marking analysis of the chemical composition of steels, cast irons and non-ferrous alloys, spectrographs (ISP-30, DFS-13, DFS-8) and quantometers (DFS-41, DFS-51, MFS-4, “Papuas-4”) are widely used. , the basis of which is the generally accepted scheme of emission spectral analysis. When performing an analysis, a pulsed electric discharge is excited between two electrodes, one of which is the sample being analyzed. Radiation from the atoms of the elements that make up 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 qualitative analysis, the resulting spectrum is interpreted using tables and atlases of the spectra of elements. For quantitative analysis of a sample, one or more analytical lines of each analyzed element are selected from the spectrum.

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

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 allows fully automated analysis of spectra. In addition to the indicated devices, enterprises use steeloscopes (Fig. 3.3) of the “Spectrum” type for rapid 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 (SLV) allows such analysis to be carried out in workshops, warehouses, and on large parts without destroying the surface.

Spectral analysis of metals is carried out according to GOST standards, 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;

tin-free 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 a sample can be obtained either by placing it on the anode of an 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 more preferable because:

has a higher sensitivity (up to 0.0005%);

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

the sample is not heated.

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

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

Rice. 3.3. Optical diagram of the steeloscope: 1 - light source (electric arc between the electrodes, which serve as the samples under study); 2 -- capacitor; 3 -- gap; 4 -- rotating 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 of chemical composition.

Control of mechanical properties. This type of control is carried out at the Central Plant in accordance with the requirements of STP and TI. The content and scope of control of the mechanical properties of metal products supplied to the enterprise are determined by the grade of metal, delivery condition and purpose in accordance with the normative and technical documentation.

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

For tensile testing of round, square and hexagonal metal, 2 samples, 60 mm long from either end of the rolled product, are taken from each batch.

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

For tensile testing of rolled sheets, two samples 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 the rolling direction. For tapes and strips, a sample 400 mm long is taken from one roll of each batch at a distance of at least 1 m from the end of the roll.

To test the impact strength of sheets, strips with a thickness of at least 11 mm, pipes with a wall thickness of at least 14 mm, rods with a diameter of at least 16 mm, 2 samples measuring 11×11×60 are taken from either end next to the tensile test sample. mm for the production of samples measuring 10×10×55 mm. From rolled products with a thickness of up to 10 mm, 2 samples are taken to make samples measuring 5×10×55 mm. To test impact strength at sub-zero temperatures, 3 samples are taken.

If results are obtained that do not comply with the certificate, the test is repeated on twice the number of samples. If repeated tests yield negative results 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 incoming inspection passport with test tables attached.

Conclusion

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

In order to increase their competitiveness, an increasing number of enterprises are realizing the need to create a quality management system and certify it 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 an authorized person, and that his responsibilities include:

Ensuring the development, implementation and maintenance of a quality management system;

Monitoring the implementation of internal audits of the quality management system, analyzing its effectiveness;

Submitting reports to the director on the functioning of the quality management system, analyzing its effectiveness.

We also found out that 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;

Organizing accounting and monitoring the implementation of measures and documents of the quality management system, conducting internal audits;

Improving the quality management system.

Under the new requirements, the organization must establish and specify in detail product/service measurement requirements, including acceptance criteria. Measurement must be planned to confirm their compliance with the detailed requirements. The organization should plan to use statistical methods to analyze data. In problem analysis, causes must be identified before corrective or preventive actions can be planned. Information and data from all parts of the organization must be integrated and analyzed to assess the overall performance status of the organization. Based on objective information, methods and means for continuous process improvement are determined.

Effective functioning of the quality system involves the creation and operation of an information retrieval system, corrective actions and results obtained in the field of quality.

Having a certified quality system at an enterprise is not an end in itself. Firstly, a number of industries have their own specific certification systems. Secondly, ISO 9000 certification is a necessary but not sufficient element of competitiveness. And thirdly, recognized leaders of the market economy create their own, more developed and advanced quality management systems. But there is no doubt that the absence of an appropriate quality system deprives an enterprise of the prospect of surviving in conditions of fierce competition.

List of used literature

1. Rebrin Yu.I. Quality management: Textbook. Taganrog: TRTU Publishing House, 2004. 174 p.

2. Great Soviet Library, TSB; http://bse.sci-lib.com/article092724.html. Date of access: 11/11/2011

3. Gludkin O.P. Methods and devices for testing RES and EVS. - M.: Higher. School., 2001 - 335 p.

4. Unofficial GOST website; http://rgost.ru/index.php?option=com_content&task=view&id=925&Itemid=29. Date of access: 11/11/2011

5. Build Consultant; http://www.skonline.ru/doc/6809.html. Date of access: 11/11/2011

6. A.I. Orlov Mathematics of chance: Probability and statistics - basic facts: Textbook. M.: MZ-Press, 2004, - 110 p.

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

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