Automatic particle counting

The oil sample is filtered through a 0.8 µm membrane filter, and thereby collecting all wear particles of interest. The filter is then inspected by using a fully automatic microscope, which will detect and measure all particles of interest on the filter membrane. Filter inspection by microscopy is the most accurate way of particle counting, as traditional particle counters are unable to distinguish between wear particles, air- and water bubbles, soot etc. Our method can be used on all fluids that can be filtered (lube oils, hydraulic oils, water-glycol solutions etc). The results from the particle counting is presented according to your desired standard (NAS 1638, ISO 4406, SAE AS4059 etc).

Detection through Wear Debris Analysis

Manual wear debris analysis

The oil sample is filtered through a 0.8 µm membrane filter, thus collecting all wear particles. The filter is then analyzed in a manual microscope equipped with up to 1250x magnification. By using different light filters, various structures in the particles can be observed. This can help us identify the cause of wear. By compiling different images, 3D models of the particles can be created, ma-king it possible to inspect microstructures. By looking at particle colour, we can to some degree determine what type of metal the particle is composed of. The oil can also be subject to wet micros-copy, where an oil drop is applied between to glass plates, and then inspected in the microscope. This is ideal for identification of microbial growth.

Measuring water content

Water content is measured by using the Karl Fischer method (ASTM D4928). Increased water content can indicate penetration of water to the system. Elevated water content will disrupt the oils lubrication or hydraulic properties, as well as cause corrosion. Microbial growth is also facilitated by increased water content.

Normal analysis for good condition monitoring

To achieve good condition monitoring of a system or machinery, we recommend performing particle counting, water content mea-surement and manual inspection of wear particles. With the information retrieved by using these methods it is possible to recom-mend reasonable actions to secure stable operations and a high running time.

Microbial growth and biofilm

Microbial growth and biofilm formation in lubrication and hy-draulic fluids is an increasingly widespread problem. If wet micros-copy reveals clear signs of microbial growth, such as free bacteria, fungal hyphae, fungal spores or biofilm, we recommend performing fluorescence microscopy to confirm the presence of such conta-minants, as well as quantify the amount of bacteria. Bacteria can exist in virtually any environment, and it is the quantity and type of bacteria that determines the severity of the problem. To fully map the extent of the problem, we can also perform a DNA analysis to identify the individual species of bacteria present, in order to create an effective plan for removal of bacteria.

3D RENDERING OF MULTIPLE IMAGES: Cylindrical bronze particle from a supporting bearing caused by extensive wear in hydroelectric power turbine. The particle has been shaped by the rotating movement in the bearing.

3D IMAGE: Three dimensional image of a wear particle found in a ball bearing. 500x magnification.

RESULTS: In our reports we focus on presenting results and recommendations in an accessible and non-complicated format.

TITRATION: Karl Fischer titration is a widely used analytical method for quantifying water content in a variety of products. The fundamental principle behind it is based on the Bunsen Reaction between iodine and sulfur dioxide in an aqueous medium.

Air release properties

Air bubbles in hydraulic media can cause wear in the same way as metallic particles. Sudden changes in pressure can cause cavitation, where the air bubbles implode, generating high temperatures and shearing forces, which can cause pitting of metal surfaces. The time it takes for air to be released from a hydraulic media can therefore be an important property to measure. Different oils have different air release properties, and a comparison can be a valuable tool when choosing hydraulic media, as well as determining when an oil change may be in order. The air release property is measured according to the ASTM D3427 standard

SEM analysis for element identification

If manual inspection of wear particles reveals large amounts of particles of unknown composition, we will recommend performing a Scanning Electron Microscopy (SEM) analysis. In a SEM ana-lysis, the wear particles will be bombarded with electrons. A 3D image of the particles will be generated, and by detecting secon-dary electrons, different elements can be identified, such as iron, carbon, aluminum, copper, manganese etc. In this way, we can identify from what component in the system the particles come from based on the specific alloy of the material. Wear on single components can hence be discovered, and corrective actions im-plemented.

SEM: Scanning Electron Microscopy image of biofilm from a thruster installation on an offshore supply vessel. Colour has been added to enhance different structural components, as well as different types of microorganisms.

BACTERIA: Fluorecence microscopy of free reigning bacteria. All the green dots are bacteria containing a colour agent with fluorescent properties.

SEM: Metal particle of unknown composition. See below.

SPECTRUM: Element analysis of the above particle. It consists mainly of iron (Fe), manganese (Mn) og titanium (Ti). It is likely to originate from high-alloy shaft steel.

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