Jorge M.E. Saffar, Maria Luísa C. Costa Reis, Eunice M. Ferreira Marques, Daniel S. Alves de Lima
VALIDATION OF THE 5 kN FORCE STANDARDS MACHINE OF THE AEROSPACE TECHNICAL CENTRE OF BRAZIL – FIRST PHASE

This paper presents the methodology and results of an interlaboratory comparison currently in progress for the validation of forces generated by the 5 kN force standards machine (MCCC) designed and manufactured for the Low Force Laboratory (LBF) of the Aerospace Technical Centre (CTA), Brazil. Reference forces were generated by the 5,2 kN force standards machine of the Isaac Newton Laboratory of the Technological Centre Foundation in the State of Minas Gerais (CETEC). Results obtained in the first phase of the intercomparison have shown that the errors and the best measurement capability are larger than expected. Further investigation in the MCCC initial nominal range is to be carried out in the second phase of the comparison.

Boris Katz, Liron Anavy, Itamar Nehary
THE CALIBRATION SYSTEM OF FORCE MEASUREMENT DEVICES - CONCEPTIONS AND PRINCIPLES

Developed, put into practice and used the universal automatic system MABA-2000 for calibration of force measurement devices in accordance to ISO 376-1999, ISO 7500-1999 and manufacturer requirements. The system includes a set of load cells from 1 kN to 5 MN, amplifier DMP-40 (HBM), computer and accessories. Mathematically proved the possibility of calibration in points, which vary from series to series, proved, and confirmed the application of calculation of formulas accuracy deviation and repeatability in accordance to ISO 7500-1999. This approach increases the productivity and simplifies the calibration process. Software MABA-2000 permits to communicate the measurement line “load cell-amplifier-computer” and to perform calibration process on mode ON-LINE: input of the measurement data, indications of the deviations in real time, calculations of the uncertainties, calculations of the calibration results and output of certificate. For calibration by method of Dead Weight a computer automatically selects a set of standard weights as a function of the True Force and value of gravity acceleration. The strict and precise method of the measurement results’ rounding optimizes the value of uncertainty. Calculation of interpolation polynoms of 1^st, 2^nd, 3^rd degree is done automatically too, and does not require additional resources or time. The software MABA-2000 includes also the subroutine for the measurement load rate and calculates uncertainty in accordance to customer requirements.

Stuart Davidson
THE USE OF UV ACTIVATED OZONE FOR THE CLEANING OF PRIMARY PLATINUM-IRIDIUM KILOGRAM MASS STANDARDS

The cleaning of primary platinum-iridium mass standards is traditionally achieved using the nettoyage-lavage process developed at the BIPM. This manual cleaning method is notoriously difficult to reproduce, particularly at laboratories other than the BIPM. An alternative, operator independent, method for the cleaning of primary mass standards, using UV activated ozone, has been investigated and the results are reported.

Lutz Doering, Erwin Peiner, Michael Balke, Uwe Brand
CALIBRATION OF LOW-FORCE STYLUS PROBES

Traceable measurement of micro forces involved during stylus profiling is described. For this purpose two methods based on a transferable cantilever-type force standard were developed using the cantilever deflection and the output voltage of an integrated piezoresistive strain gauge. Force calibration was performed with commercial stylus instruments in the range of 10 - 200 µN.

Luiz Carlos Cabral de Freitas, Stella Regina da Costa, Rafael S. de Oliveira
A NEW METHODOLOGY FOR HARMONIZATION IN THE DISSEMINATION OF THE TORQUE QUANTITY IN BRAZIL

The purpose of this paper is to show the needs and to propose a new methodology for a better dissemination of torque quantity in Brazil. Starting traceability from the Force, Torque and Hardness Laboratory (LAFOR) in the National Institute of Metrology, Standardization and Industrial Quality (INMETRO), an improvement to the Primary Torque Standard was necessary. In the same way, the acquisition of new transfer and reference standards, together with the development and adoption of new methods for torque calibration systems characterization, are important for a better acting of Inmetro’s Accreditation and Laboratorial Proficiency Testing Division (DICLA). In the methodology for that dissemination and harmonization, this proceeding lists what are important points to be on focus.