Several dust control firms have publications which specify capture veloocities; I don't remember noticing aluminium chips, (there's no such thing as aluminum by the way), mentioned so you might have to look at the nearest alternative. A good source for capture velocities is the DCE, Dust Control Engineering, Handbook which is available on their website.

Conveying speed ought to be slightly less than the capture velocity but is irrelevant anyway because if you can't catch it you can't convey it. There are dozens of portable/movable units on the market anyway.

So your suction pipe diameter is a factor of the largest chip size, also mentioned in the handbook, & thats all you should need to know. Solids loading is not relevant either because it depends on what is being captured, which in turn seems to depend on the chip breaking arrangement which will govern the economics of the operation.

If you have considered loading the chips from a collecting hopper the operation will be bedevilled by the minimum lubrication regime.

Your main problem must be the implied interfence to the toolpath geometry. ■

Dear Tiaan,

As mr John Gateley already said, the capture velocity is a value to start with.

This capture velocity can be estimate by knowing the chip size and the chip form and the density of Al.

The air velocity should then be at least 4 to 5 times the calculated floating velocity, at

any place where you want to capture the Al-chips.

Blowing the chips to a collecting zone can also help.

Estimating the amount of chips to be removed might lead to pipesize and airvolume

and pressure drop.

Lubricant will also be captured.

What will happen to the chips that are not captured?

As you are better aware of the real circumstances, we can only come up with

guesses, that could be points of attention

succees

teus ■