Effect of Several Gas Atmospheres on Hydraulic Fluid Shear Stability

摘要

The sonic-shear stability of polyisobutylene and polymethacrylate solutions in oil was examined under several gases and at pressures up to five atmospheres. Tests were conducted in a pressurized sonic treatment cup under nitrogen, hydrogen and helium atmospheres. Comparison tests under air were made at one atmosphere. Results indicated that sonic-shear stability varied inversely with gas solubility for all the gases, except air at one atmosphere. Both polymer solutions displayed highest viscosity losses under the helium atmosphere. The use of gases other than air and sonic test cell pressurization showed promise as a modification of the sonic-shear method, to make it more closely reflect mechanical-shear tests. (Author)