Procedure for conformity assessment of automated systems for control and accounting of natural gas energy

Abstract

The paper analyses the regulatory and technical requirements for the construction of automated systems for control and accounting of natural gas energy. Typical diagrams of gas energy accounting systems (gas measuring stations) are presented. Existing metrological requirements for accuracy classes in regulatory documents for the specified systems are provided. The approaches to conduct testing during the conformity assessment are considered. A procedure for conducting testing during the conformity assessment of the gas energy accounting system using a modular approach has been developed. The expediency of applying accuracy classes A, B, C and D according to DSTU EN 1776 during the conformity assessment is substantiated. The stages of testing and inspections of the installation of pressure, pressure drop, temperature, meter, flow chromatograph and energy calculator sensors are described. The necessity of using calibrated gas mixtures, the component composition of which corresponds to the transported gas, for testing the chromatograph is argued. The calculation of the maximum permissible error of the automated system for control and accounting of natural gas energy for two ranges of the gas volume flow, depending on the gas meter, is presented. The calculation under the condition of creating a new gas energy accounting system and supplementing the existing gas volume accounting system with a flow chromatograph are considered. The calculation of the error of the automated system for control and accounting of natural gas energy using the method of variable differential pressure is also presented.