1.1 This standard specifies the evaluation of the shear stability of polymer-containing fluids, measures the percent viscosity loss at 100℃ of polymer-containing fluids when evaluated by a diesel injector apparatus procedure that uses European diesel injector test equipment. The viscosity loss reflects polymer degradation due to shear at the nozzle.
1.2 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.
2 Normative References
The following normative documents contain provisions which, through reference in this
standard, constitute provisions of this standard. For dated reference, subsequent amendments to, or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest editions of these documents are applicable. For undated references, the latest edition of the normative document referred to applies.
GB/T 265 Petroleum Products-Determination of Kinematic Viscosity and Calculation of Dynamic Viscosity
GB/T 8029 Calibration Fluid for Diesel Injection Pump
CEC L-14-A-93 Determination of Mechanical Shearing Stability of Polymer Containing Lubricating Oil
DIN 51382 Determinations for Shear Stability of Polymer Containing Lubricating Oil Using Diesel Injector
3 Terms and Definitions
For the purposes of this standard, the following terms and definitions apply.
3.1
Kinematic viscosity
A measure of the resistance to flow of a fluid under gravity.
3.2
Calibration pressure
The recorded gauge pressure when calibration fluid RL34 undergoes a viscosity loss of 2.75 to 2.85 mm2/s at 100℃ when the recorded gauge pressure is within the range of 13.0 to 18.0MPa.
3.3
Viscosity loss
The loss in viscosity determined from the difference in kinematic viscosity at 100℃ of pre-sheared and post-sheared fluid.
3.4
Percent viscosity loss
Viscosity loss, as defined in 3.3.2, divided by the pre-sheared viscosity, and reported as a percent.
4 Summary of Test Method
A polymer-containing fluid is passed through a diesel injector nozzle at a shear rate that causes polymer molecules to degrade. The resultant degradation reduces the kinematic viscosity of the fluid under test. The percent viscosity loss is a measure of the mechanical shear stability of the polymer-containing fluid.
