ASTM D5621-07(2013) PDF

Scope: 4.1 This test method was developed using Test Method D2603–91.

4.2 This test method permits the evaluation of shear stability with minimum interference from thermal and oxidative factors that may be present in some applications. It has been found applicable to fluids containing both readily sheared and shear-resistant polymers. Correlation with performance in the case of hydraulic applications has been established.

1.1 This test method covers the evaluation of the shear stability of hydraulic fluids in terms of the final viscosity that results from irradiating a sample of the hydraulic fluid in a sonic oscillator.

1.2 Evidence has been presented that a good correlation exists between the shear degradation that results from sonic oscillation and that obtained in a vane pump test procedure.²

1.3 This test method uses millimetres squared per second (mm²/s), an SI unit, as the unit of viscosity. For information, the equivalent unit, cSt, is shown in parentheses.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

ASTM D5621-07(2013) Referenced Document

ASTM D2603 Test Method for Sonic Shear Stability of Polymer-Containing Oils
ASTM D445 Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (the Calculation of Dynamic Viscosity)
ASTM D6022 Standard Practice for Calculation of Permanent Shear Stability Index

2020 ASTM D5621-20 Standard Test Method for Sonic Shear Stability of Hydraulic Fluids
2019 ASTM D5621-19 Standard Test Method for Sonic Shear Stability of Hydraulic Fluids
2007 ASTM D5621-07(2013) Standard Test Method for Sonic Shear Stability of Hydraulic Fluids
2007 ASTM D5621-07 Standard Test Method for Sonic Shear Stability of Hydraulic Fluids
2001 ASTM D5621-01 Standard Test Method for Sonic Shear Stability of Hydraulic Fluid
1994 ASTM D5621-94 Standard Test Method for Sonic Shear Stability of Hydraulic Fluid