Oil analysis in modern diagnostics of machine condition
Today many efficiently-run companies use the oil analysis as the main diagnostics method of machinery such as pumps, compressors, combustion engines, gearboxes, transformer, etc. This method is not widely used in many industries. In some industries the tribodiagnostics of friction pairs is much more effective than vibration diagnostics and thermography. BALTECH recommends performing the vibration analysis and balancing using BALTECH VP-3470 and energy audit and thermography with BALTECH TR-01500.
Among all the technical diagnostics methods the tribodiagnostics is considered very effective as according to the available data 95% of all the failures can be accurately detected by the oil analysis. Thus the oil analysis provides reliable information about the technical condition of bearings, seals, lubricant, presence of ferromagnetic (metal) and nonferromagnetic particles, watering, viscosity parameters and lubricant quality.
- The oil diagnostics has the following advantages:
- there is no need to shut down a machine;
- dismounting is not required;
- detection of failures at the early stage of development;
- oil replacement based on its actual condition instead of operation duration;
- low labour intensity
It should be noted that the equipment condition and cycle life more than 60-70% depends on the oil condition which is affected by various factors:
- thermal influence;
- ambient atmosphere influence;
- chemical interaction with various materials;
- electric field exposure ( for transformer and insulating oil), etc.
This leads to the oil deterioration and degradation.
The oil degradation several times increases rate of engine wear and breakdown. To timely detect the changes in oil quality and contamination it is necessary to perform a systematic oil monitoring.
Therefore the question about how to check the oil condition is critical. This question has two aspects: How to check the new oil and how to check the used oil?
To solve the first question one should rely upon the corresponding ISO standards that specify all the necessary characteristic and estimation methods for all types of oil. The control methods for new oil are specified in terms of every individual oil parameter (viscosity, flash temperature, inflammation, total base number, etc).
To check the used oil condition one can also refer to the corresponding ISO standards. The oil analysis can be performed by conventional methods or advanced methods of tribodiagnostics (tribodiagnostics of friction pairs).
Tribodiagnostics is the advanced preventive method of machine condition estimation that provides accurate and reliable information about its technical condition and amount of wear. However today this method is not widely used in the industry. The tribodiagnostics is widely used only for maintenance of gas turbine engines.
Tribodiagnostics of machinery consists in estimation of its technical condition with regard to oil formulation and wear debris concentration using special devices and equipment (oil analyzer, atomic emission spectrometer, infrared spectrometers, X-ray fluorescence analyzers, etc.). The oil sample analysis with use of this instruments makes it possible to detect the concentration in oil any elements from which the machine parts are made and which experience friction. Having this information allows specialists to determine the component average wear and plan the corresponding repair works.
Ferrography makes it possible to diagnose the wear type and friction intensity based on the particle form, size distribution, surface condition and materials. This method can be used not only for detection of magnet metal particles but also for detection of nonmagnetic materials such as blacklead, bronze, aluminium, brass, etc. BALTECH offers you the mini- laboratory for oil and lubricant analysis 5200 that allows specialists to perform the diagnostics of used oil using the ferrography analysis and data about particle size and quantity detected according to ISO 4406 (or NAS 1638) with use of built-in laser particle counter. This data makes it possible to determine the wear type, failure location and defect severity. For example, spherical particles in oil indicates fatigue cracks on friction surfaces, and flaky particles indicates fatigue flaking. Particles in size up to 2 um give evidence of corrosion.
Besides, the mini- laboratory for oil and lubricant analysis 5200 makes it possible to check the oil chemical condition- degradation severity due to oxidation, nitration, sulfonation, as well as water and fuel contamination. The mini- laboratory thus allows specialists to determine the reasons of changes in oil properties- chemistry contamination or wear.
In recent years one of the most commonly used methods of the oil analysis is infrared spectroscopy. BALTECH offers you the effective portable infrared analyzer 1100. This analyzer has all the advantages of infrared Fourier spectrometer, i.e. it detects such important oil properties as water content, total base number, total acid number, soot content, glycol, antiwear additives and oil decomposition. Besides, it doesn’t require use of solvents and sample preparation typical for a traditional lab infrared analysis. The portable infrared analyzer 1100 thus provides you with reliable information about the most critical oil properties within 2 minutes on-site.
As a rule, the portable infrared analyzer 1100 should be used with the portable viscosimeter 3050 for on-site detection of kinematical viscosity which provides you with the full information about the oil condition.
Sometimes it’s enough just to get an answer on the question: «Can the used oil be operated further?» In this case you can use the express analyzer BALTECH OA-5000 which gives you the answer within 2 minutes. It also allows creating trends in oil quality changes thus predicting possible equipment defects. The analyzer BALTECH OA-5000 is delivered with the technique of oil drop test performance for detection of such diesel failures as incomplete burning, bad oil filtration and local overheating. This analyzer in used by the Russian refining companies.
A very important moment in oil analysis is a proper sample collection, as the improper sample collection can lead to incorrect equipment diagnostics. To learn how to make accurate oil sample selection, how the main oil properties are changed during equipment operation and how to perform equipment diagnostics with the oil analysis for wear detection at the early stage of its development BALTECH has worked out a new training course TOP – 105 «Tribodiagnostics. Foundation of machine lubrication».
We invite all the technical specialists to receive this training. This training course covers all the main aspects of tribology and provides detailed information about methods of detection of oil properties according to ISO and ASTM. The training course includes a practical part with use of special equipment and methods of on- site oil analysis. The participants will have the opportunity of working with the oil analyzer BALTECH AO-5000, portable infrared analyzer 1100 and portable viscosimeter 3050.
We invite all the technical specialists to our seminars in Germany (Luebeck).