Petroleum Testing Equipment

Application
This test method covers the evaluation of the cavitation corrosion and erosion-corrosion characteristics of aluminum automotive water pumps with coolants

Method
This test method consists of pumping an aqueous coolant solution at 113°C (235°F) through a pressurized 103-kPa (15-psig) simulated automotive coolant system.

An aluminum automotive water pump, driven at 4600 r/min by an electric motor, is used to pump the solution and to serve as the object specimen in evaluating the cavitation erosion corrosion effect of the coolant under test. The pump is examined to determine the extent of cavitation erosion corrosion damage and is rated according to the system given in Table Photographs of typical eroded pumps after testing Appear in the Appendix

Uses
This test method can be used to distinguish between coolants that contribute to cavitation corrosion and erosion corrosion of aluminum automotive water pumps and those that do not. It is not intended that a particular rating number, as determined from this test, will be equivalent to a certain number of miles in a vehicle test; however, limited correlation between bench and field service tests has been observed with single-phase coolants. Field tests under severe operating conditions should be conducted as the final test if the actual effect of the coolant on cavitation corrosion and erosion-corrosion is to be appraised. It is also possible, with proper control of the test variables, to determine the effect of pump design, materials of construction, and pump operating conditions on cavitation corrosion and erosion-corrosion damage

HYDROLYTIC STABILITY OF HYDRAULIC FLUIDS ASTM D 2619   

• The sample of 75 gram of fluid plus 25 gram of water and a copper test specimen are sealed in a pressure type beverage bottle. The bottle is rotated, end for end, for 48 hours in an oven at 930C at 5 rpm.
• Consists of rotating type oven with digital temperature controller and beverage bottle rotating drive system with 5 RPM.
• Beverage bottle capacity 200ml
• Capacity to accommodate 2/4/8/12 bottles at a time.
• Power supply : 230 +10% Volt AC, 1 Phase, 50 Hz.

Test results
The test measures the following:

• Acid number change
• Total acidity of water
• Weight change of copper
• Appearance of copper strip
• Total sediment weight

Safety precautions
Because the test involves a glass bottle that can contain up to 200 kPa (2 atm) of air and water vapor at 93°C, it is recommended to wear a full face shield and heavy woven fabric gloves when handling the sample container.

Importance of hydrolytic stability
Hydrolytic stability is a fluid’s ability to resist chemical breakdown when exposed to water, which is a common contaminant in hydraulic systems.

The ASTM D 5800 test method measures the evaporation loss of lubricating oils, particularly engine oils, by heating a sample to 250 °C and drawing a constant flow of air through it. The loss in mass of the oil is then determined. The results are reported as a percentage of total loss.

Here are some details about the ASTM D 5800 test method:

• Sample placement – A measured amount of the sample is placed in an evaporation crucible or reaction flask.
• Heating – The sample is heated for 60 minutes.
• Temperature measurement – The specimen temperature measuring device should have an accuracy of 0.5 °C or better and a resolution of 0.1 °C or better.
• Evaporation loss calculation – The evaporation loss of the sample is determined by the difference in mass of the sample before and after heating.
• Precision – Inter laboratory tests have shown that the four procedures in the test method yield statistically equivalent precision.
• Before the first test, the unit should be turned on with the heat and vacuum pump for 15–30 minutes