shipvibration
Marine/Ocean
catalytic fines: are there any shipboard tests to ascertain
percentages?guidance on remedies.
thanx
percentages?guidance on remedies.
thanx
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catalytic fines 3
- Thread starter shipvibration
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I believe the simple answer to your question is no - there are no simple ways to measure cat fines. The laboratory procedure is quite time consuming, and requires some fairly sophisticated equipment (mass spectroscopy analyser ??). In essence you are looking for small quantities of the catalyst, than standard tests (e.g. sediment) would not be sufficiently sensitive to detect.
You should insist on catalytic fines measurements from your fuel suppliers as part of the standard analysis, or alternatively send samples to an independent laboratory (clearly the latter is not always logistically possible). The usual indication is Aluminium content (in ppm).
The effect of cat fines on your engines can be immensely damaging. Cat fines have properties similar to valve grinding paste. Damage could occur to plant auxiliaries (pumps, valves etc.) but more seriously to fuel pumps, injectors, pistons/rings, liners etc. I've heard instances where direct costs run to hundreds of thousands of pounds.
If your fuel is within limits (I believe 80ppm aluminium for marine fuels ??) then correctly operating centrifuge equipment should see you are safe. If it is not, then even 80ppm could be damaging. If high levels of cat fines are present in the fuel, then you may find the centrifuge equipment blocking rapidly (build up of quite solid "cake" in the bowl). The temptation is to bypass the centrifuge to keep the engine running, but the risk is that it won't run for long !!!
Hope this helps.
You should insist on catalytic fines measurements from your fuel suppliers as part of the standard analysis, or alternatively send samples to an independent laboratory (clearly the latter is not always logistically possible). The usual indication is Aluminium content (in ppm).
The effect of cat fines on your engines can be immensely damaging. Cat fines have properties similar to valve grinding paste. Damage could occur to plant auxiliaries (pumps, valves etc.) but more seriously to fuel pumps, injectors, pistons/rings, liners etc. I've heard instances where direct costs run to hundreds of thousands of pounds.
If your fuel is within limits (I believe 80ppm aluminium for marine fuels ??) then correctly operating centrifuge equipment should see you are safe. If it is not, then even 80ppm could be damaging. If high levels of cat fines are present in the fuel, then you may find the centrifuge equipment blocking rapidly (build up of quite solid "cake" in the bowl). The temptation is to bypass the centrifuge to keep the engine running, but the risk is that it won't run for long !!!
Hope this helps.
can provide plenty of fuel analysis information.
Also specialise in onboard fuel test sets.
You can also visit the web site for useful information.
Also specialise in onboard fuel test sets.
You can also visit the web site for useful information.
The fines are indeed very dangerous.
In about 1979 I was on an old 1944 Portline Freezer ship converted to a live sheep carrier, trading between the Gulf and Australia. The engines were LB Doxfords with high-pressure fuel rails feeding valve controlled pressure lift injectors.
We had a faulty Sharples type purifier and the Fines build up in the daily service tank.
On entering Fremantle in Australia the tanks were changed over and we got a very high contamination of the fines.
This caused the control valves in the piston type fuel pumps at the rear of the engine to seize and smash the control rods.
Thus when we went to slow the Port engine it would not respond.
Following the mass panic as we were heading straight towards the river. We managed to swing her about with only a kilometer to go. The only way to shut the engine down was to turn off the fuel. It took several Kilometers to stop.
Upon inspection we found both engines were badly effected.
Had we not turned we would have taken out the main road bridge at the end of the port.
DMC
In about 1979 I was on an old 1944 Portline Freezer ship converted to a live sheep carrier, trading between the Gulf and Australia. The engines were LB Doxfords with high-pressure fuel rails feeding valve controlled pressure lift injectors.
We had a faulty Sharples type purifier and the Fines build up in the daily service tank.
On entering Fremantle in Australia the tanks were changed over and we got a very high contamination of the fines.
This caused the control valves in the piston type fuel pumps at the rear of the engine to seize and smash the control rods.
Thus when we went to slow the Port engine it would not respond.
Following the mass panic as we were heading straight towards the river. We managed to swing her about with only a kilometer to go. The only way to shut the engine down was to turn off the fuel. It took several Kilometers to stop.
Upon inspection we found both engines were badly effected.
Had we not turned we would have taken out the main road bridge at the end of the port.
DMC
Cat fines will not block purifiers. They will likely first result in damage to fuel pumps and piston rings liners.
The test method in a laboratory is to ash the sample and then create a solution which is injected into a atomic absorbtion (AA)tester.
There is no cheap tester for ship's use. You have to use testing agencies such as DNV,Lloyds, BSI-Inspectorate.
A simple check on the ship to check for presence of abbrasive contaminants is to place some fuel between smooth glass plates, apply some pressure and rotate one plate against the other. Inspect the plates for scouring. This will not tell you how much but will show you have a problem.
rgds
The test method in a laboratory is to ash the sample and then create a solution which is injected into a atomic absorbtion (AA)tester.
There is no cheap tester for ship's use. You have to use testing agencies such as DNV,Lloyds, BSI-Inspectorate.
A simple check on the ship to check for presence of abbrasive contaminants is to place some fuel between smooth glass plates, apply some pressure and rotate one plate against the other. Inspect the plates for scouring. This will not tell you how much but will show you have a problem.
rgds
One ready method I have tried is to place a drop of oil between two clean glass disks and rub them together. Glass is quite hard and if you see scratches on the plates, it indicates something is wrong. Not sure whether this will work everytime. It is more to do with peace of mind. What we normally do is not to use the fuel till full analysis come from the lab.
BRGDS
Shippie
BRGDS
Shippie
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