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Plastic extrusion processes require chilled water to function correctly, no matter water cooled chiller? air cooled chiller? scroll compressor chiller? or screw compressor chiller? portable chiller? or others, it can both satisfy your processing working.
To determine the size of chiller you’ll need for your plastic process cooling application, follow this formula:
1. Calculate the pounds of material per hour being processed.
2. Determine how many pounds per hour are required for each ton of cooling capacity.
3. Determine if the extruder or any auxiliary equipment will require chilled water.
4. Size the equipment cooling capacity.
5. Combine the process and equipment cooling requirements.
6. Size your chiller by rounding up to the closest standard unit.
The extruder manufacturer can supply the flow rate through the feed throat and the approximate flow rate to control the barrel in a water-cooled extruder.
Also to consider:
How much heat supplied by viscous shear heating has to be removed?
Extruder size
Processing temperature window size
Info to size extrusion chiller:
Extruder diameter and length
Number of zones
Extruder hp
Connection sizes
Throughput
Materials being processed
Melt temperature
Cooling required if it is known in either BTU/hr or tons

Please contact me if you need water chiller for the processing:
Contact: Grace Zhang
Mobile: +86-18615626360
Email: grace@mgreenbelt.com
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2017/9/18
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It has been months since I logged into my G+ account.

I hardly recognize the changed G+.

Yeah, you got me: I'm an Old Guy. A very busy old guy.

Recently I found an alternate way to cool my apartment.

http://hg47.blogspot.com/2017/06/my-bathtub-air-conditioner-rocks.html

This link has nothing to do with extrusion, but it does illustrate how flexible thinking "outside-the-box" can be a "game-changer."

The way to look at any extrusion operation is as something that we will all look back in five years as a laughable joke.

If we do not find new and even "crazy" ways to extrude, we won't be extruding much longer.

Harv

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Dry Free PET sheet extusion line!
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2017/4/10
5 Photos - View album

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I just got written up. It was a “verbal warning” delivered in written form; a red page detailing my personal failures, which I had to sign. Then my boss, well, one of my bosses, took the page away, and did not give me a copy, so now I am unclear on exactly all the things I did wrong. Hey, I was in somewhat of a daze when I signed the thing.

But I get the “Big Picture.” It was a “Housekeeping” issue.

I work 12-hour shifts, 8:00pm to 8:00am for now (our shifts keep changing). The guy I usually take over the shift from keeps leaving me partial gaylords of virgin material to use: in other words, he gets a Gaylord of powder that has so many clumps that it will not load into the hopper without constant babysitting by someone, and he sets it aside and uses another Gaylord. So he turns over the shift to me with 2 or 3 or 4 partials that he refuses to use, that I have to use because I am Night Shift, and the big Bosses come in the morning. I can’t have partial gaylords cluttering up the floor.

I tried asking him nicely to stop leaving me partials.

I tried yelling at him.

I tried damning him to hell and eternal fire.

Nothing worked.

Then last Sunday Night at 8:00pm I took over the shift from him, and after he left I discovered that he left me a disaster. Over by the grinder was about 10 gaylords that hadn’t been broken down, that each had a little bit of virgin or regrind in their plastic bags—basically, for the whole weekend everyone had been shoving their mess over into the corner, ignoring it to keep things running. Also, nearly-empty gaylords of virgin and nearly-empty gaylords of regrind were put beside lines that were not running (just hide it here—maybe no one will notice).

I only had one line running, but I only had one operator, and this was a part that overworked the down-stream operator, and I had my hands full just keeping things running up-stream.

I did much of the material handling that the downstream operator was “supposed to be doing.”

Now, my personal bias is: if you hand me lines that are making good parts, I am willing to walk over dead bodies to continue making good parts. But the company I work for now has a different bias. I think it is the “Broken Window Theory.”

(New York City had a terrible crime problem awhile back, and the new Police Chief took an unusual method of solving it. He started cracking down on the little stuff: graffiti, broken windows, turnstile jumpers; visually things improved.)

In the future, if I am faced with a similar situation, I will let the line(s) go down or make bad parts; but what I will absolutely do is make sure when the Big Bosses on Day Shift walk in that the plant is in order.

I will shut lines down to clean up.

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sheet extrusion lines and compounding pelletizing lines:
PP,PS,PET,ABS,PMMA,PC,PVC,EVA,TPO,GPPS,XPE,XPS,etc
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2016-07-14
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TEMPORARY QUICK-FIX FOR MATERIAL LOADER PROBLEMS. Extruder running too fast for the hopper loader?  Is the length too long from where the material is to the hopper you want to fill?  Can’t invest just now in a needed higher capacity loader?  Line clog-ups can be eliminated, and pellet flow rate can be increased about 25% by an air-assist at the furthest distance from the hopper to be loaded: for a 2”-I.D. hose, cut a 1/4” hole and insert a 1/8th inch I.D. air tube curved so the air-blow assists pellet travel.  WARNING: This works so well, that it’s easy to let this “band-aid” solution become a permanent solution to a shop floor problem.  But it is not cost-effective.  Air power is expensive.

I'm starting to notice a new trend in Extrusion where Standardization trumps Process Efficiency.  The National and International Power Players in Extrusion will order a complete extrusion line when they want more production output, where the extruder and die and cooling apparatus and puller and cutter are all pre-designed and engineered for a specific line speed.  

In this bureaucratic environment it is essential that multiple identical extrusion lines in different factories and different nations perform to design parameters.  When the Extrusion Big Boys want more parts they install more lines; they don't want to hear about retrofits or changes to "improve" their God-like moves.

In practical terms what does this mean for you?  If you work in a small extrusion shop, and you find a better way, a faster way to make parts, you have to sell your boss and the owner on the change.  If you work for an International Extrusion company, and you find a better way, a faster way to make parts, you have to sell your boss, your boss's boss, your boss's boss's boss, and the majority within a committee at the head office.  Good Luck with that.

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How To Fix Chronic Water Marks In Extrusion

 Usually, water marks are easy to fix.  Sizing sleeves inside a vacuum tank have spray rings to cool them.  Turn down the water pressure.  In an open water cooling tank, turbulence where the extrudate first enters the water can cause bubbles to stick to the moving plastic (other visual blemishes can also be caused by turbulence as the extrudate first enters the water).  Change the setup to reduce turbulence at the initial entry point.

(see article for more)

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Sometimes an extrusion line speed-up results more from politics and persistence, than anything else.

We used to make filament for [name of company deleted] 3D printers.

ABS and PLA filament. 

It was obvious to everyone that the line speed was limited by the turning speed of our coiler.  The issue was when we switched from a full coil to an empty coil; if the line was running too fast we would just get a big mess instead of the smooth start of a new coil.

The “powers that be” set the line speed at 1300 on the puller.  The maximum speed of our puller was 2000. 

POLITICS?  I had access to the owner.  We were friends.  When I mentioned the possibility of buying a faster coiler, he just laughed.  We also discussed perhaps doing dual extrusion with two filaments from a single die—but it was obvious that designing new tooling and buying a second coiler wasn’t going to happen.

PERSISTENCE?  So I looked carefully at the design and internals of the coiler we were using, and gave the owner three inexpensive ways to speed up the line using our existing equipment:

1) We could change the internal chain gears that powered the coiler to speed it up.

2) We could change the motor’s belt-driven pulley ratio to speed up the coiler.

3) We could increase the inside diameter of the core that we used to wind up the filament so the current rotational speed would adequately deal with an increased line speed, and increase the width of the coil to compensate for this.

The owner was not impressed.

So about twice a week, every week, I brought up my three cheap line speed up ideas.  I repeatedly pestered the owner.  Over and over. 

After three or four weeks, the owner gave in and maintenance changed the belt-driven pulley ratio.

Yay!  We maxed out the puller at 2000. 

But after a couple of days at the higher production speed, my boss, the Day Shift Supervisor, slowed it down to 1800 and left me a note to leave it at 1800.  Well, the guys on my shift didn’t have any problem with the 2000 speed, but apparently his guys and/or the guys on second shift did.

Oh, well.  Even at 1800, I got a 38% line speed-up!
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