Розробка датчика диференційного тиску для авіакосмічного застосування. Метрологічне забезпечення і вибір первинного перетворювача

Abstract

The main requirements for the differential pressure sensor developed by JSC "Element" by SE "DB" Yuzhnoye" order are given. It is shown that the most important criteria when choosing a primary transducer were the requirements, firstly, to control the pressure of chemically aggressive medium – rocket fuel, and secondly, to perform measurements of relatively low differential pressure under operating overpressure (linear) pressure. The upper limit of changes in linear pressure is an order of magnitude higher than the limit of the measured differential, and it is necessary to minimize the additional error due to the effect of operating overpressure. Information search data are given, because of which the primary transducers that best meet the specified requirements are selected, namely, Keller PD-10L series sensors. A sensor developed and manufactured on the basis of the selected primary transducer is briefly described. The main attention is paid to the description of metrological support of transducer development and testing and the results of experimental studies of its characteristics in terms of long-term stability and the effect of operating overpressure on the output signal when changing the controlled differential pressure in the measurement range. The given information concerns the creation of a specialized stand for the study of this effect, equipped with an imported meter that provides control of differential pressure from zero to 16 bar under the influence of operating overpressure 150…166 bar with an error of not more than ± 0,1 %. It is explained that the need to create a stand at the enterprise is due to the lack of such equipment and measuring equipment in the Ukrainian centers of metrology and standardization. Based on the results of the analysis of requirements for the application of the developed sensor performed together with the customer, a rational way of presenting the transformation function was selected, which minimizes the measurement error in the most responsible conditions.