State primary standard of unit for torque GET 149-2023

The problems of metrological support for high-precision torque measuring instruments, which have a measurement range that includes torque values of less than 1.0 N·m, are considered. The areas of activity in which torque measurements are important are shown. The history of the development of the highest level reference base as an important link in the metrological support of torque measurements in the Russian Federation is described. Brief information is provided on the level of development of the reference base in this field of measurements abroad. As a result of the increase in the number of torque measuring instruments, the upper measurement limit of which is less than 1.0 N·m, there was a need to expand the measuring and calibration capabilities of the Russian Federation in this area, in particular, in the range of 0.1–1.0 N·m. The composition of the State primary standard for the unit of torque GET 149-2023 is given. The operating principles of the four reference installations included in GET 149-2023 and the structure of the reference are described. GET 149-2023 includes the created modern reference installation EU-250-2 for reproducing, storing and transmitting a unit of torque in the range of 0.1–200 N∙m. The results of studies of the reference installation EU-250-2 and the metrological characteristics of GET 149-2023 are presented.