Design, development and fabrication of 50 kN force standard machines to provide national traceability in force measurement to the industries

The present paper describes design, development and performance of a 50kN dead weight force standard machine and 50kN force comparator machines established at Regional Reference Standard Laboratories (RRSL) to provide national traceability to users without much degradation in uncertainty in disseminating force scale. This chain of measurement expedites the process of dissemination of the force unit from the national level to the user industries economically without much degradation in uncertainty. The expanded uncertainty associated with the force measured by the dead weight force machine is ±0.005%, which increases to ±0.05% in the case of force measurement by the force comparator machines. An excellent agreement is found in the force measurements within the stated uncertainties of the individual machines used; (i) national force reference standard, (ii) RRSL Dead weight force machine and (iii) the force comparator machine which establishes the compatibility of these force standard machines based on different operational principle.