Application White Papers

These application papers, authored by Spectro Inc., provide valuable insights and information for customers using our instruments. A brief description of each topic is provided, and the complete document is available for download in PDF format by clicking on the paper's title.


LaserNet Fines, A New Tool for the Oil Analysis Toolbox (1.0M .pdf file, 8 pages)
Related product: LaserNet Fines.

(Article for Practicing Oil Analysis Magazine, Noria Publishing http://www.practicingoilanalysis.com/.)

"Every once in a while, a revolutionary tool evolves that will change the way the routine is perceived. LaserNet Fines may do just that by providing particle counting and particle classifying with one simple instrument."


Comparison of Wear and Contaminant Particle Analysis Techniques in an Engine Test Cell Run to Failure (1.1M .pdf file, 10 pages)
Related products: LaserNet Fines, Analytical Ferrograph, Spectroil M/C.

Three oil analysis techniques were applied to used oil samples from an engine that was run in a test cell. The three techniques were Automatic Wear Particle Shape Classification, Ferrography and Spectroscopy. The analytical results from the techniques were compared to determine their effectiveness in working individually, or in combination, to rapidly determine engine condition based on oil analysis.

This paper details and reviews analytical results from the three techniques over the 540 hours of engine operation. A total of 31 samples were taken from start to finish. All samples were analyzed with an atomic emission spectrometer and the analytical results for twenty-one elements were recorded. The same samples were analyzed with the LaserNet Fines-C Particle Shape Classifier in order to obtain particle distribution and particle shape classification information. Ferrograms were prepared for morphological analysis with an optical microscope from key oil samples during break-in, steady wear, and towards the end of the engine test.

The summarized data shows good correlation among the three techniques. Each in itself was able to identify wear trends. However, from a practical standpoint, the data show that spectroscopy combined with automatic wear particle shape classification provides a rapid means to determine detailed engine condition, and can be used together as a screening tool before ferrographic analysis needs to be undertaken.


On-Site Liquid Gas Turbine Fuel Analysis for Trace Metal Contamination (99k .pdf file, 7 pages)
Related product: Spectroil M/F.

Contamination levels of liquid fuel entering the combustor of a gas turbine must be low to avoid high temperature corrosion and fuel system fouling. Accordingly, each of the major industrial gas turbine manufacturers has strict contamination limits which must be met in order to comply with the warranty of the turbine. The responsibility to assure compliance lies with the owner of the power plant and can only be guaranteed with on-site fuel analysis for contaminants and ash-forming metals.

This paper discusses the various fuel analysis techniques available to the gas turbine user. It will review each technique's ability to meet the need for fast and precise on-site analytical data. It will be demonstrated that the rotating disc electrode (RDE) atomic emission technique is the preferred analytical method for on-site fuel analysis. Actual field experience will be used to illustrate and discuss compromises that may be necessary to meet the objectives of the gas turbine user, fuel treatment supplier and turbine manufacturer.

 
New Developments and Functional Enhancements in RDE Used Oil Analysis Spectrometers (172k .pdf file, 7pages)
Related product: Spectroil M/C.

Spark emission spectrometers using the rotating disk electrode (RDE) technique have become the workhorses and primary analytical tool of most machine condition monitoring programs based on oil analysis. This paper describes several new developments that have put new life into this established and well accepted used oil analysis technique. They include performance enhancements, automation and additional capabilities.

Digital technology has been applied in the design of excitation sources, optical and readout systems to greatly improve stability, maintainability and capabilities. A robotics system has also been developed to provide automated and unattended sample introduction and analysis. Several recent new inventions and developments have also augmented the applications and capabilities of the RDE technique. They include, 1) the ability to analyze large wear particles, 2) a modification to include the ability to analyze diesel engine coolants and water, 3) the development of an additional small optical system to make it possible to analyze sulfur in oil and fuel and 4) a modification to analyze the conductivity of a used oil sample in the same step as the normal wear metal analysis.


Analytical Tools to Detect and Quantify Large Wear Particles in Used Lubricating Oil (429k.pdf file, 7 pages)
Related product: Spectroil M/C.

Machine condition monitoring through oil analysis is a proven and cost effective maintenance management technique. Periodically, however, the ability and the need to detect large wear particles is questioned and papers have been published which attest to the fact that spectroscopy is more or less blind to the larger wear particles in an oil sample. Nevertheless, used oil analysis has been shown to be extremely effective in predicting potential machine failures. It is thus not unrealistic to ask the question "are there benefits to additional tests, and will they significantly improve the probability of detecting a potential failure that may otherwise be missed by conventional analytical methods?"

This paper discusses three techniques that can be used to improve the ability of optical emission spectrometers to detect and quantify large wear particles in lubricating oil. They are an acid digestion differential method, ferrography and rotrode filter spectroscopy.

 
Machine and Lubricant Condition Monitoring for Extended Equipment Lifetimes and Predictive Maintenance at Power Plants (396k .pdf file, 13 pages)
Relates to all Spectro Inc. products.

Predictive maintenance has gained wide acceptance as a cost cutting strategy in modern industry. Condition monitoring by lubricant analysis is one of the basic tools of a predictive maintenance program along with vibration monitoring, performance monitoring and thermography.

In today's modern power generation, manufacturing, refinery, transportation, mining, and military operations, the cost of equipment maintenance, service, and lubricants are ever increasing. Parts, labor, equipment downtime and lubricant prices and disposal costs are a primary concern in a well run maintenance management program. Machine condition monitoring based on oil analysis has become a prerequisite in most maintenance programs. Few operations can afford not to implement a program if they wish to remain competitive, and in some cases, profitable.

This paper describes a comprehensive Machine Condition Monitoring Program based on oil analysis. Actual operational condition monitoring programs will be used to review basic components and analytical requirements. Case histories from several power plants will be cited as examples of cost savings, reduced equipment downtime and increased efficiencies of maintenance programs through a well managed oil analysis program.

 
Rotrode Filter Spectroscopy, Does It Have a Place in the Commercial or Military Oil Analysis Laboratory? (121k.pdf file, 7 pages)
Related product: Spectroil M/C.

Several papers have been published which attest to the fact that spectroscopy is more or less blind to the larger wear particles in an oil sample. Nevertheless, oil analysis has been shown to be extremely effective in predicting potential machine failures. It is thus not unrealistic to ask the question; "Are there benefits to additional tests such as rotrode filter spectroscopy (RFS), and will they significantly improve the probability of detecting a potential failure that may otherwise be missed by conventional analytical methods?"

The rotrode filter spectroscopy (RFS) method makes use of the fact that the carbon disc electrodes used in rotating disc electrode (RDE) spectrometers, such as the ones used in JOAP, are themselves porous. A fixture is used to clamp the discs so that oil can be drawn through the outer circumference of the discs when a vacuum is applied to the inside of the discs. The particles in the oil are captured by the disc. The oil is then washed away with solvent, the disc is allowed to dry, and the particles are left on the disc electrode so that they are vaporized and detected when run on the RDE spectrometer. A multi-station fixture is used so that a number of samples can be filtered at once. The procedure is fast, and therefore economical to perform.

The rotrode filter spectroscopy (RFS) method was introduced at the previous International Condition Monitoring Conference. Since that time, a patent has been issued for the technique, and a number of systems have been fielded with the objective to enhance the capabilities oil analysis laboratories.

This paper reports on the experience to date with the RFS technique in actual machine condition moni-toring applications. It will investigate the capabilities and applicability of the RFS technique as an additional test to improve the probability of detecting and identifying large wear particles that may otherwise be missed by standard spectroscopic techniques.

 
Lubricant Analysis for Gas Turbine Condition Monitoring (495k .pdf file, 12 pages)
Related product: Spectroil M/F.

Analysis of used lubricating oil is a fast evolving technique for predictive maintenance with any closed loop lubricating system such as those in gas and steam turbines, diesel and gasoline engines, transmissions, gearboxes, compressors, pumps, bearings and hydraulic systems.

Based on analysis of periodic oil samples, a laboratory diagnostic report is sent to the personnel responsible for the equipment to warn of any possible problem or to make a specific maintenance recommendation. The entire process, from sample taking to the diagnostic report, should take less than 48 hours to be effective. These reports, when combined with statistical analysis and trending, can provide an insight to management personnel on the effectiveness of the program, efficiency of the maintenance department, repair status of equipment, recurring problems, and even information on the performance of different lubricants.

Condition monitoring by oil analysis can be broken down into two categories, debris monitoring to measure the trace quantities of wear particles carried by the lubricant away from the wearing surfaces and lubricant condition monitoring to determine if the lubricant itself is fit for service based on physical and chemical tests.

 
Diesel Engine Coolant Analysis, New Application for Established Instrumentation (52k .pdf file, 9 pages)
Related product: Spectroil M/F.

This paper describes recent work to calibrate and modify Rotating Disk Electrode (RDE) arc emission spectrometers for the analysis of engine coolant samples; a mixture of approximately 50% water and 50% glycol. The technique has been shown to be effective for the analysis of wear metals, contamination and supplemental coolant additives in ethylene and propylene glycol. A comparison of results for coolant samples measured by both Inductively Coupled Plasma (ICP) and RDE spectrometers will be presented. The data correlates extremely well on new and relatively clean coolants. However, not surprisingly, RDE results are sometimes higher for samples containing particles larger than a few micrometers.