Comisión Nacional de Energía Atómica (CNEA)'s labs at Pilcaniyeu, in the steppes of Río Negro. In 1983 INVAP designed and built here the Argentine plant of uranium enrichment with cuadrupole spectrometers to determine the isotopic ratio of uranium-235 and uranium-238 in hexaflouoride gas

INVAP has designed, built and commissioned several quadrupolar mass spectrometers for the determination of the radioisotope ratio of ²³⁵U/²³⁸U in gaseous UF₆.

These spectrometers were successfully used in the U-enrichment plant of the Argentine Atomic Energy Commission (CNEA) in Pilcaniyeu, Argentina.

The equipment comprises a gas-loading system an analysis system both built in AISI 304 steel, and each having its own vacuum system. These reach high vacuum and use nitrogen cold traps for the material not used in the analysis.

The vacuum system for the analyser includes uses ionic pumps, with a battery-fed redundancy for the case of an electrical power supply failure.