Hi, guys, thank you very much for the suggestions, here follows some
comments

Pierre Desrochers wrote:

>You could run the parts on a felt conveyor.  The contact of the two should
>at leats absorb the dropplet.  Then you skim the conveyor to make it kess
>filled with the oil.
>
That's a good one, but the guys that make the mechanics says it is unfeasible :-/ (don't understand why, I'll have to insist in some kind of explanation now)


Roland wrote:

>Don't know anything about the process, but, how about;
>rinse the parts with an alcohol or kerosene just before the test, blow dry
>with hot CO2, test, then re-apply oil afterwards,
>or, if possible, let the belt dip and pass through a bed of kerosene,
>deeper than the part, and do the visual tests? looking into the bath.
>Cameras would be boxed with a glass front and sit just into the surface.
>Then blow off excess fluid and re-apply oil.

The oil should not be removed from the parts, it's syntherized metal, 16% of its weight must be oil, and the tests should be the final process, the conveyor belt leads the parts to packing. If I build an enclosure over the belt, probably the hot CO2 or perhaps Nitrogen would be part of a solution

But the idea of doing the tests with the parts dipped, not in kerosene, but in oil, that's a good one! Gonna think more about that!


M. Adam Davis wrote:

> Well, the problem you're having is that you can't have the oil on the
> part, and they can't have the oil off the part.  It's a catch-22.

Yes, it looks like :-(

> Personally, I'd work harder on the air.  If the current blower leaves
> a drop or two on, then use 3 blowers or air jets.

We're already working on this, but it's difficult, the surface tension of the oil and the turbulence of the air jets always makes funny things. We're trying to find ideal pressures for several air jets, but the oil droplets are not willing to cooperate.

> What are the tests you're running that the oil messes up?  Can you use
> the solvent and then re-apply oil after the tests?

Sorry to not have mentioned this before: we're ruining a "machine vision" inspection (a camera, video-capture board and a special program looking for scratches, chips, and things like that), and this  is why the oil droplets have to be removed: the system might guess that it is a defect on the part.

> Will the tests work directly in the air jet so the particular test
> spot will be oil free?

no, because close to the air jets some drops of oil might reach the camera lens

> Have you considered torching the oil?  :-)

Yes! But our client didn't like it ;-)


John Ferrell wrote:

>How about a slow moving absorbent tape wiping the conveyor belt on the
>bottom in a continuous manner.

That's another point, if the conveyor belt gets too wet with the oil,the program wont be able to locate the part, that it is a clear blob over a dark background (the conveyor belt) and if the oil starts to reflect lots of light, we're going to start missing some parts, so I think we're going to build such thing.


Thanks a lot for the suggestions! You are great! I think we can manage a mix of them all to get a final solution.

Francisco

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