Resumo:
To accomplish measures and analyses of acid liquids in a steel company environment is not a
trivial mission; sensor and conventional analyzers, although in the beginning of the application present
convergent results of good capacity to reproduce and for repetition, it doesn't keep them with the same
efficiency, due to the aggressiveness of these acids to the primary elements of the transducers. This
paper has the objective to develop industrial applications in the metallurgical segment making use of
technologies of the ultra-sonic sound waves, specifically in liquid environment with characteristics of
high aggressiveness as it is the case of the Hydrochloric acid, the objective of our investigations. In this
case study, a prototype of tank of glass fiber was developed, in a way to allow the necessary
rehearsals, simulating a real situation of the tanks of hydrochloric acid of the Acid Pickling Lines of CSN
– Companhia Siderúrgica Nacional, located in Volta Redonda - RJ. The strategies for the choice of the
transit-time methods of propagation of reflected sonic pulse or technique pulse-echo, common to the
professionals of non destructive ultrasonic sound waves rehearsals was possible to development a
system to inspection the position of the steel plates into the hydrochloric acid tank. The first contribution
based in the results obtained in our experiments show good capacity to reproduce and for repetition for
measure the position of the steel plate describing a loop inside a tank of hydrochloric acid. The second
contribution based in the conclusions and suggestions for future works in the variation of concentration
of the hydrochloric acid solution in function of the variation of speed of sound propagation. Great
volumes of hydrochloric acid materials of high harmful capacity both for man and for the environment,
are handled for obtaining metallurgical products with ranges of control of intrinsic quality restricted and
are directly responsible for the quality and operational costs of pickling lines.
