In a message dated 12/17/1999 12:33:24 PM Central Standard Time,
[log in to unmask] writes:
<< We have had an inline cleaner for about a year. We occasionally see a
surface mount part that has been ripped off the PWB, taking pads with it.
We think the problem might be that the component is being caught in the
conveyor when coming off the conveyor, on to our rotating table. It is not
always the tallest component or an end component. Has anyone else ever had
a problem like this? How did you solve it? >>
Hi Jan!
Ahh yes, been there, done that, and even gotta tee-shirt! Hehehe...
At a past employer, we had one of them merry-go-round dealies and the problem
that we had was that there were many times that the operators wouldn't be so
quick to get the boards off the turntable as they should, and then boards
would wind-up coming out of the reflow oven (that where we had our
turn-table) and falling on top of the ones still on the turn-table...we had
cracked caps, bent leads, and ripped-up pads just like you.
If your operators are diligent and making sure that's not happening, then it
could be your cleaner. You didn't say what kind of cleaner you have. If you
have one with a double-belt that lays on top of the boards as they go through
the machine to keep them from flying around, then maybe it's not your
cleaner. But if you don't have the double-belt kind, then it might be the
cleaner.
Here where I'm at, and at the last place I worked, I have cleaners that have
a single belt, and there's a lot of boards that I have to put into baskets to
keep them from getting damaged. The cleaner at my last place was a REAL
beast! It had 10-hp pumps and 15-hp blowers and would make the boards sound
like marbles in a dryer ping-ponging around inside the machine if you didn't
put them into baskets.
You can cut the pressures down on your sprayers and blowers, but then you
lose cleaning effectiveness. Putting things into baskets and making sure
someone is at the end to catch em' is about the only way to make sure things
don't get damaged.
The only other way is to buy another machine that has a double belt to keep
the boards secure while going through the cleaner, and then setting things-up
at the exit end with a magazine board unloader...but that's gonna cost some
bucks.
-Steve Gregory-
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