Zharkevich O.M., Bekmurzin D.S

Karaganda State Technical University

 

METROLOGICAL ACCURACY OF ENGINEERING AND MANUFACTURING DOCUMENTATION

 

Nowadays standards are metrological instructions 2267-2000 «Recommendation. State ensuring system of measurements uniformity. Ensuring of effectiveness measurement in management process. Metrological accuracy of engineering documentation» define the main goals and objectives of metrological accuracy of engineering and manufacturing documentation. According to the above standard «Metrological accuracy of engineering documentation» is an analysis and evaluation of product warrantee, measurement parameters, as they relate to measurement accuracy, methodology, measuring devices and their repair inadequate [1].

The reasons are obvious: insufficient metrological knowledge in metrology make it impossible to control the parameters of manufactured products (both in entirety and in part, process equipment and most often measurement devices). The production must be stopped, when an errors are found because of a lack products with uncontrolled parameters, material losses and accidents of disasters.

Metrological accuracy in manufacturing due to accurate of technology may cause of manufacturing equipment, assembly drawings and explananory notes. Test procedures is characterized by new tasks and challenges, resultants in improved metrological devices. This applies to processing results by computers, to ensure the safety of products and physical quantities and their units.

Metrological accuracy of construction of the engineering products must start no later, than at the development stage of technical specifications. To start later would make it difficult or impossible to control finished products. These requirements are found during of technical specification stage in the comprehensive plan. It is necessary to include the development of special measuring devices or measurement procedures.

The effectiveness of metrological accuracy increases if it start early. Metrological errors and their consequences are detected, therefore metrological accuracy must begin before development of the basic engineering and manufacturing documentation, with the application for development of the technical project and the technical proposal. In the beginning the «preprojects documents» stage engineers can evaluate the possibility of control parameters for future product by universal measuring devices, which evaluate the prospects of future manufacturing and metrological insurance [2].

Standard 2267-2000 stated, that erroneous or insufficiently informed solutions of metrological accuracy are revealed. Recommendations on specific issues of metrological support usually are provided. Metrological accuracy contributes to solve technical and economic problems in the development of technical documentation.

On the one hand, secondary accuracy requirements must establish control of parameters. On the other hand, functional metrological accuracy is their goal. The goals and objectives of accuracy for different types of documents are presented in the above standard. This list includes all documents that are needed to established standards of accuracy or that contain information about devices and methods of measurements. In particular, this list includes applications and technical terms and proposal, schematic drawings, explanatory notes, calculations, program and test methodology, operational documents and repair documents.

The preliminary and prospective projects of technical documentation and working process are: route maps, map sketches, manufacturing instructions, list of accessories, manufacturing process and transaction cards.

In conclusion, it can be confirmed, that quality products require metrological accuracy in term of engineering and manufacturing documentation [3]. The overall goal of metrological accuracy ensuring the effectiveness of metrological insurance, implementation of general and specific requirements for metrological support by the best methods and devices. Specific objectives of metrological accuracy determine the purpose and content of engineering documentation.

 

References:

1)                MI 2267-2000 «Recommendation. State ensuring system of measurements uniformity. Ensuring of effectiveness measurement in management process. Metrological accuracy of engineering documentation».

2)                Besfamilnaya L.V., Rezchikov V.I., Sokolova L.G., Shvandar V.A. Economics of standardization, metrology and quality of products - M.: Publishing of standards, 1988.  – p. 188.

3)                Yakovlev Y.N. Metrological accuracy of  engineering documentation.- M.: Publishing of standards, 1992. – p. 10.