"Bar_turned_Components_mfg" wrote in
oups.com:

I produce a part which has a 5mm "ball" press fitting operation. The
ball is pressed in the hole at a depth of 20mm from the face, this I do
on a power press. Lot sizes are about 100000nos

Operations are sequenced below:
10. A ball is dropped into the hole of the part by hand.
20. Place the part on the press.
30. Push the press lever by his leg.
40. The punch 26mm long then rams & press fits the ball.
50. Lift the part and put it in processed bin.

I have not been able to think of a way to get 100% process capability.

I have to do 100% visual segregation, even then there is no 100%
percent guaranted result.


Kamal,
A simple method would be to make the insertion punch in the following
way:
Spring load the insertion punch by mounting it in a cylindrical holder
that has a spring inside of it and slot milled through one side. The
insertion punch will need a cross drilled and reamed hole in it that will
accept a pin that will be inserted into the punch through the side of
cylindrical holder. Use a pin that is long enough so that it can be used
to actuate a micro switch if the ball is not in place. When the ball is
in place the pin should not be able to reach the micro switch. As far as
what the micro switch does, well that depends on your set up. You could
use it to actuate a blow off that would eject the part away from the good
ones. You could also use it to actuate a buzzer or a red light. You could
even use it to actuate a counter so that at the end of the shift you can
compare the number of parts rejected to the counter, thereby giving you
100% confidence that all of the parts in the finished product container
have a ball in them. If it were me I would use the blow off in
combination with the counter, and make an accounting at the end of each
shift.


--

Dan