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Author Topic:   Co extrusion and crosslinking
raoulsoni
Member

Posts: 4
From:Calgary, Ab, Canada
Registered: Mar 2007

posted September 27, 2007 01:49 AM     Click Here to See the Profile for raoulsoni     Edit/Delete Message   Reply w/Quote
Hi all,
Here's a tough one. Is it possible to co extrude PEX A,B,C making it the inner layer and HDPE bimodal as outer layer? and will the product be spoolable after crosslinking has occured.
Lets say pipe wall thickness of 6 millimeters.

I will wait for your inputs.

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Tom C
Moderator

Posts: 894
From:Brodheadsville, PA USA
Registered: Jun 2001

posted September 27, 2007 06:41 AM     Click Here to See the Profile for Tom C     Edit/Delete Message   Reply w/Quote
I'm sure I don't know the ultimate answer, but doesn't the answer also depend on the tube diameter, thickness of the PEX layer, and spool diameter?

------------------
Best Regards,

Tom Cunningham

www.ExtrusionTechnicalServices.com

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raoulsoni
Member

Posts: 4
From:Calgary, Ab, Canada
Registered: Mar 2007

posted September 27, 2007 11:09 PM     Click Here to See the Profile for raoulsoni     Edit/Delete Message   Reply w/Quote
Tube diameter 4.430 inches(112.5mm)
Spool DIA 100 inches. Inner wall of PEX about 4 to 6 mm.

The reason I am asking is this. I would like to design a high pressure pipe with a inner layer of crosslined pex for High heat application. Now I am not sure if the pex after crosslinking will be spoolable.
I could increase my reel hub (dia) but then I am faced with transportation problems.

Has anyone heard of crosslinked spooled pipe.

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Tom C
Moderator

Posts: 894
From:Brodheadsville, PA USA
Registered: Jun 2001

posted September 28, 2007 07:49 AM     Click Here to See the Profile for Tom C     Edit/Delete Message   Reply w/Quote
The flexural modulus of PEX is, at most, 2 times PE. A spool twice the diameter of the minimal bending diameter of normal PE might work.

------------------
Best Regards,

Tom Cunningham

www.ExtrusionTechnicalServices.com

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