Oil analysis, testing, appraisal and evaluation

OIL ANALYSIS

TESTING PROCEDURES
Oil analysis is the evaluation of the oil itself and any contamination that is present. The information derived from the following tests looks for different types of wear and contamination. Each test looks at a different aspect of the oil. This is the reason for the different tests. The tests are as follows:

PHYSICAL TESTING:

VISCOSITY
The viscosity test measures the thickness of the oil. The oil is heated and run through the viscosity bath. The results are then compared to the new oil specification. This test is valuable in determining the condition of the oil and an indicator of water contamination and oxidation.
WATER CONTENT (GREATER THAN 1%)
Water content above 1% is detected in the basic oil analysis.

SPECTROANALYSIS

Spectroanalysis is the analysis of the metal content and additive package. This test checks 19 elements and reports them in parts per million. These numbers represent the elements less than 5 microns in size. The spectrometers design limits its detection level to 5 microns and below. To evaluate the particulate larger than 5 microns, other test methods must be implemented.
The spectroanalysis is used to look for bearing or bushing wear in the form of copper, lead, or tin. The spectroanalysis also looks at dirt levels in the form of silicon. Wear in pumps, housings, and other points of contact can be evaluated using this information. It is important to remember that these are small particulate. If there are large particles of metals in the oil, larger than 5 microns, the spectroanalysis will not detect them. The larger particulate will be detected in the particle count and or the filter analysis, if the particulate are large enough.
The additive package of the oil can be identified and evaluated using the spectroanalysis.

PARTICLE ANALYSIS

The particle count is the single most important part of the report to measure the efficiency of the system filtration. The particle count measures all particulate in the oil larger than 5 microns.
Particulate include: dirt, carbon, metals, fiber, bug parts, etc.
The particle count can be done using either laser or optical methods. The laser method reports the quantity, size and distribution of particulate, but not what they are. The optical method gives a quantity, size, distribution and identification.
A combination of these two methods are used in OAL's PARTICLE ANALYSIS. Through the use of the two methods, we can provide the most representative analysis available.

OTHER TESTS:

Other tests are needed in some situations. For example, some systems have a low tolerance to water content or acidity levels. Additional testing is required in these situations. The following is a brief description of additional tests and the information they provide:

WATER BY KARL FISHER - ASTM D-1744
This test measures water content down to 50 parts per million, which is .005%. It is used in turbine system analysis, servo systems and any other system that has low tolerance.
TOTAL ACID NUMBER - ASTM D-664
This test measures the acidity level of a system. Over time the acidity level of the system increases. This can be detected with this test. In addition, some forms of contamination can also increase the acidity levels.
FOAM TEST - ASTM D-892
In some systems high amounts of carbonization of oil occurs and pump cavitation is a problem. In these cases the oil could be foaming and causing these charastics. This test measures the ability of the oil to resist foaming when air is injected into the oil in a controlled environment. In many instances the problem, once identified, can be corrected by changing to a different type of oil.
FLASH POINT - ASTM D-3828
Each oil has a known flash point when it is porduced at the refinery. In some situations, contamination such as solvent, fuels, or other flammable substances are present in the system. This test is an indicator of this type of contamination. The procedure uses the new oil flash point as a base line, for example 525 degrees F. If the sample in question has a flash point of 250 degrees, then the oil could be contaminated with a flammable substance.
INFARED ANALYSIS
In many situations the customer is looking for the source of external contamination. This is initially discovered by a high particle count or short filter life. In some cases the contamination is due to a cross contamination of fluids. In this case we can run a foot print of the oil in question to determine if there is cross contamination.
In addition to cross contaminatoin situations, this test can also give information on oxidation, nitration, water content, and sulfur levels.