Load Distribution Measurement with Fuji Prescale: The Easiest and Simplest Defect-Detection Mechanism

High-rotation assemblies, like industrial air compressors or high pressure oil pumps are finely balanced machines that are very sensitive to load and alignment discrepancies. Even the slightest deviation in loads can cause catastrophic failures and even larger loss of productivity. Here is a case study of how the Fuji Prescale high-pressure films can be used to quickly and accurately detect any load discrepancies on the contacting surface between the ball-bearings and bearings sleeves on the machine body.

Load distribution as defect detection mechanism

High-rotating assemblies, like turbo fans, are very sensitive to load distribution discrepancies between the ball-bearing and chassis contacting surfaces (sleeves). Ball bearings that do not evenly distribute the axis loads onto the pump chassis means that with each rotation of the fan, some parts of the contacting surface get over-loaded, while some parts barely make contact with the ball-bearings.

When this cycle is repeated thousands of times per minute, for a long time, the contacting sleeve of the chassis gets fatigued, that results in miro-fractures and eventually can lead to a complete failure of the high pressure pump.

This is why load distribution needs to be a part of both the construction and servicing process of high-rotation assemblies.

Measuring Load Distribution

Ball-bearings need to establish full contact with the housing sleeve with as close to perfect overlap as possible, so that all the loads from the axis can be evenly distributed onto the engine body. Here is how the Fuji Prescale pressure sensitive film can help you determine the load distribution.

1. First, you will need to place a high-pressure Prescale film (numbers 4 to 8 on the pressure sensitivity scale) between the ball bearing and the two-parts housing sleeves.
2. Then tighten the bolts to specified tightening force without rotating the axis.
3. Next, remove the film and inspect the pressure distribution to mark any load discrepancies.

Image source

If the developed pressure sensitive film is evenly red, as is on the "Good" image above, then the load distribution is correct. However, if the developed film turns out to be significantly discolored like the "Not Good" example, it is obvious that the ball-bearing does not sit properly in the housing sleeve, and such discrepancy can eventually lead to a severe engine malfunction.

Thanks to this very simple diagnostics procedure, you can avoid catastrophic failures of the machine.

• Takes very little time
• Is cost-effective
• Gives you a graphic representation of where the problem lies



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