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Does anyone have any experience they would like to share with regards to the expected Iron levels on the Cyclo BBB4 speed reducers?

We are a new mining operation and have 5 of these units driving conveyor head pulleys.  The first oil samples all came back with high iron counts (spectro analysis)  and also high magnetic iron counts. All are over 120 ppm. Is this normal for these units?


**The Commissioning team mistakenly put a Mobil Synthetic gear oil in these 5 reducers.  Sumitomo told me specifically DO NOT USE. They have seen failures with the reformulated Mobil SHC gear oils and therefore they are not approved for use. 

I caught this screw up early but all reducers ran with the wrong oil for approximately 1 month. 

So now on our first oil sample I am seeing high levels of iron in each of these 5 units so I am being very cautious. I am however concerned when I see these levels in other gearboxes.

Any input would be appreciated.



Greg M.



Tags: Expected Oil Sample Iron Levels, Cyclo, BBB4

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I am taking sample from the dipstick with a drop tube/suction pump. I am careful not to touch bottom of gearbox reservoir when I take the sample, while the gearbox is running. I am seeing 166ppm iron on ICP spectro and 176ppm magnetic iron count on one particular gearbox. 

As previously noted this is a baseline oil sample, which seems to me to raise flags due to the high iron count. This gearbox only holds 5.9 litres of oil. I have attached the ISO /opc count. Thee also seems to high.  I have done a baseline vibration reading on this gearbox approximately 2 months ago. I don't have access to the data right now as I am away from site. But I will be reviewing it as soon as I return to work in 2 days time.

I have mentioned that am not familar with this cyclo style gearbox and was looking for some feedback to whether or not high iron counts do occur in these units.

But the fact remains the same that high iron counts like this will damage bearings and gears.

Thanks for your feedback.



Hi Jason,

The elevated iron levels on all 5 of our cyclo gear units after 2.5 years running have somewhat stabilized around 50 ppm using spectro, and we are also checking the total magnetic content every sample. We haven't had any failures yet (knock on wood). We are changing oil whenever the level on the spectro results go close or over 100 ppm.  Vibration readings are taken regularly, and no considerable increase from baseline measurements from 2 years ago. However, one of the 5 units show a more unique pattern in the spectra data.


Thanks for the response Greg.

We're at 25/23/15 with 12 cutting, 0 sliding, 139 fatigue, so we may be a ways off yet.  It's also a somewhat unfamiliar gearbox for us, so we're not sure what to expect yet.  I'm still trying to nail down whether our sample was taken while running and if it was just a pour out of the drain fitting.  It's a non-critical conveyor drive of ours, and we've got a center bearing stocked, so even if it breaks down, we could likely be up and running in a day, but I'm trying to educate myself on what the normals are for this style of gearbox.


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