The use of a ‘Bridgman-seal’ for low-temperature hydraulics

Abstract

The design and performance of a Bridgman unsupported area seal is presented. This seal is part of a low-temperature hydraulic ram of 130 tn capacity for the Paris–Edinburgh pressure cell and allows compression at low temperatures down to 20 K using helium as the hydraulic fluid.

Keywords:

• high pressure
• Bridgman seal
• Paris–Edinburgh press
• neutron scattering

Acknowledgements

This work is the result of a continuous development effort over the last 15-years involving many colleagues and collaborators, in particular J.-M. Besson and G. Hamel (Paris), and R.J. Nelmes and J.S. Loveday (Edinburgh). Data in Figure 2 were taken from several experiments at ILL and PSI, involving Th. Hansen, L. Bove, V. Pomjakushin, D.V. Sheptyakov, M. Medarde, M. Zayed, S. Gvasaliya, B. Roessli, P. Toulemonde, and N. Rey. The authors thank K. Syassen, C. Ulrich and U. Engelhardt (MPI-FKF Stuttgart) for providing the gas compressor system, which was used in the measurements at PSI.