Some Aspects of the Implementation of Hierarchical Schemes and Traceability Chains of Measuring Instruments

Abstract

The article is devoted to the problematic issue of the regulatory framework governing the procedure for transferring units of measurement from the state primary (national) standards to the working facilities of measuring equipment. This concerns the need for further application of existing verification schemes, which have exhausted themselves from the point of view of practical application, since they now concern only the lower link, that is, working measuring instruments to be verified. The authors proposed, in accordance with the current regulatory documents, to supplement the list of documents submitted to the commission when approving new state (national) standards of physical units in terms of including hierarchical schemes. The current DSTU OIML D 5 was also analyzed in detail, in terms of the need to ensure the uncertainty relations between the steps of the hierarchy pyramid. It has been substantiated that there is no need to deliberately degrade the metrological characteristics of the standards in order to maintain the established ratio, since this is an irrational approach. For example, the authors have developed a hierarchical scheme for measuring the volume and volume of gas flow in a gaseous medium at a pressure of up to 1.6 MPa, which is headed by the National (State) primary standard for units of volume and volume flow of gas in a gaseous medium at a pressure of up to 1.6 MPa. As a practical implementation of the hierarchical scheme, the traceability chain of the Pasichna calibration unit has been demonstrated, the calibration procedure of which is carried out using the Reynolds number balancing method.

Keywords

• hierarchical scheme, calibration circuit, verification, calibration, traceability, uncertainty, standard