Type of Notification
regular notification
Date of Distribution
2018.10.18
WTO Country
Agency Responsible
Uganda National Bureau of Standards
Notified Document Details
<p style="margin:2px !important;">DUS 2074:2018, Standard test method for determination of yield stress and apparent viscosity of engine oils at low temperature, First Edition.</p>
Product
ICS Code
Covered Products
<p style="margin:2px !important;">Engine oils</p>
Description of Content

This Draft Uganda Standard covers the test method for the measurement of the yield stress and viscosity of engine oils after cooling at controlled rates over a period exceeding 45 h to a final test temperature between –10°C and –40°C. The precision is stated for test temperatures from –40°C to –15°C. The viscosity measurements are made at a shear stress of 525 Pa over a shear rate of 0.4 s–1 to 15 s–1. The viscosity as measured at this shear stress was found to produce the best correlation between the temperature at which the viscosity reached a critical value and borderline pumping failure temperature in engines.

This test method contain two procedures: Procedure A incorporates several equipment and procedural modifications from Test Method D4684–02 that have shown to improve the precision of the test, while Procedure B is unchanged from Test Method D4684–02. Additionally, Procedure A applies to those instruments that utilize thermoelectric cooling technology or direct refrigeration technology of recent manufacture for instrument temperature control. Procedure B can use the same instruments used in Procedure A or those cooled by circulating methanol.

 Procedure A of this test method has precision stated for a yield range from less than 35 Pa to 210 Pa and apparent viscosity range from 4300 mPas to 270 000 mPas. The test procedure can determine higher yield stress and viscosity levels. This test method is applicable for unused oils, sometimes referred to as fresh oils, designed for both light duty and heavy duty engine applications. It also has been shown to be suitable for used diesel and gasoline engine oils. The applicability to petroleum products other than engine oils has not been determined.

 

Relevant Documents
  1. ISO 17025  General Requirements for the Competence of Testing and Calibration Laboratories
  2. ISO Guide 34  General Requirements for the Competence of Reference Material Producers
  3. ASTM D3829-18 Standard Test Method for Predicting the Borderline Pumping Temperature of Engine Oil
  4. ASTM E563-11(2016) Standard Practice for Preparation and Use of an Ice-Point Bath as a Reference Temperature
  5. ASTM E644-11 Standard Test Methods for Testing Industrial Resistance Thermometers
  6. ASTM E1137/E1137M-08(2014) Standard Specification for Industrial Platinum Resistance Thermometers
  7. ASTM E2877-12e1 Standard Guide for Digital Contact Thermometers

 

Final Date of Comments
2018.12.17
Document Online Link (EN)
Notified Under
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