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moldingppm
19th November 2012, 04:27 PM
I have a few machines equipped with Air Blow setups. I was wondering, what does air blow do? I was to believe that you used compressed air to cool the parts before ejecting them, am I correct?

Pilot
19th November 2012, 07:48 PM
Hi,
cooling of parts by air in the tool is not used very often. Probably you mean "air blow" function. A lot of IMM in basic configuration is equiped by this function, because it is realy cheap to have it on machine. On machine (fix plate pr moving plate) is instaled air valve (one or more), which i open by this signal. It is used for demoulding of part from tool. The tool must be prepared for this function. Usually it is used for deep boxes or similar shapes. Sometime you can use it for demoulding of cups without ejectors (air is insert "under" cup and the cup is blow out).
Anyhow, you can use this air for another use. OR, you can use this signal for something. For example Negri Bossi machines are able to control this signal during cycle from "tool close" up to "ejector out" in each point of cycle or defined time from "tool close". You are able to control it like cascade for ex.

some links:
http://www.sunrisegr.com/srt_d.php?id=000152

Which machine do you have with this function?
Pilot

rickbatey
19th November 2012, 09:42 PM
Air blow is used for vacuum breaks built into eithe half of the mold, and some parts you will never make decent cycle times without it! Like buckets, bowls and cups. You can also build jets or air nozzles, use the air blast to blow the parts off the ejector pins, or out of the clamp area for faster cycle times. It's a tool and its better to have it and NOT need it, than to call and add it after the fact!! I've even used to spray mold release into the stationary half of a mold, with a paint gun full of mold release!
Rick.

moldingppm
19th November 2012, 10:14 PM
Hm, any pictures of the setup? That'd be something I'd be looking to do.

Could you use it to shorten your cooling cycle and use that during mold opening and get any better cycle times?

brentb
19th November 2012, 11:46 PM
Most modern machines have this function or option. As said, it is used for containers, cups, buckets and closures. Can blow air thru core components to demold, also with a "poppet" as Rick said, to break vacuum.

Keep on Molding

brent

rickbatey
21st November 2012, 01:10 AM
You can get some cycle improvements with certain parts/molds; but the mold has to have the means to take advantage of it.

Rick.

kelley
1st December 2012, 02:47 AM
I've used it to blow stubborn runners loose on three plate molds as well.

kelley

brentb
4th December 2012, 02:17 AM
I've used it to blow stubborn runners loose on three plate molds as well.

kelley

Me too! Ever used a "mold sweep" for that?

KOM

brent

rusty
16th January 2013, 04:24 AM
I have used air on a few tools, either to help break the vacuum on ribs or on back injection tools to operate cores and grippers built in to the tools. not always effective, but sometimes its the only way to get the tool to work.

cinazhu
28th January 2013, 01:57 AM
Most modern machines have this function or option. As said, it is used for containers, cups, buckets and closures. Can blow air thru core components to demold, also with a "poppet" as Rick said, to break vacuum.

Keep on Molding

brent

yeah, air blow is usually used for the demoulding for basins, bucket, covers, cups,etc.. The function of air blow is just like ejector pin. but with air blow, the product is not easily deformed becaue the force of air blow is on the surface, not just on a point.

kelley
29th January 2013, 05:29 PM
Me too! Ever used a "mold sweep" for that?

KOM

brent

Oh yea Brent,

We had a three plate mold with a foot and half long runner feeding two cavities we had to sweep. Thankfully this tool was later redesigned as a valve gated hot runner.

Kelley