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Author
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Topic: PTFE Ram Extrusion
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polymerguy
Senior Member Posts: 28
From:germany
Registered: Nov 2006
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posted November 16, 2006 12:17 PM
  
Can anybody suggest me solutions of the problems we face in Ram Extrusion.....Millions of thanks in advance IP: Logged |
Tom C
Moderator Posts: 852
From:Brodheadsville, PA USA
Registered: Jun 2001
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posted November 16, 2006 12:31 PM
Are you looking for a consultant?Who's PTFE are you using? What is the make of the Ram extruder? ------------------
Best Regards, Tom Cunningham www.ExtrusionTechnicalServices.com IP: Logged |
polymerguy
Senior Member Posts: 28
From:germany
Registered: Nov 2006
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posted November 22, 2006 12:23 AM
Actually we do Ram Extrusion. During Ram Extrusion of PTFE over Silver we dont get the Adhesion between the two materials. sometimes we find some cracks or voids or fibrills in the material after extrusion. Thanks in advance
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Tom C
Moderator Posts: 852
From:Brodheadsville, PA USA
Registered: Jun 2001
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posted November 22, 2006 10:41 AM
I'm not sure we are speaking the same language.In response to your inquiry here I asked several leading questions that could help direct you to answers. You ignored the questions. The adheasion question was answered in a post you made under wire and cable. Your reposted a question on fluoroelastomers several times, unchanged, even though you said you had resolved the issues in a prior posts. "What we have here is a failure to communicate!"
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Best Regards, Tom Cunningham www.ExtrusionTechnicalServices.com IP: Logged |
polymerguy
Senior Member Posts: 28
From:germany
Registered: Nov 2006
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posted December 06, 2006 01:31 PM
Thanks Tom for your reply,Previously i had posted a question related to Adhesion between silver and PTFE but the PTFE is a tape. we solved this problem with the temperature adjustment in the tapeing process and sintering process. But in this quesion we do a Ram extrusion of PTFE and moreover we have some cracks developing in the inner surface of PTFE and this leads to lower Adhesion. But the introduction of cracks and causes are not well known to me. according to my idea we had to look over the Lubricant that we use for PTFE ram extrusion and the Die design...
So i needed help in this line.
we had already found a Lubricant which is stress crack resistant.. But to go wiht the die design could you suggest me some ideal die design for PTFE ram extrusion with some ideal Reduction ratios..... thanks for your help IP: Logged |
polymerguy
Senior Member Posts: 28
From:germany
Registered: Nov 2006
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posted December 06, 2006 01:31 PM
Thanks Tom for your reply,Previously i had posted a question related to Adhesion between silver and PTFE but the PTFE is a tape. we solved this problem with the temperature adjustment in the tapeing process and sintering process. But in this quesion we do a Ram extrusion of PTFE and moreover we have some cracks developing in the inner surface of PTFE and this leads to lower Adhesion. But the introduction of cracks and causes are not well known to me. according to my idea we had to look over the Lubricant that we use for PTFE ram extrusion and the Die design...
So i needed help in this line.
we had already found a Lubricant which is stress crack resistant.. But to go wiht the die design could you suggest me some ideal die design for PTFE ram extrusion with some ideal Reduction ratios..... we use Jennings Extruder thanks for your help IP: Logged |
Tom C
Moderator Posts: 852
From:Brodheadsville, PA USA
Registered: Jun 2001
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posted December 06, 2006 05:48 PM
How hot is the wire prior to extrusion?How is the product cooled? Problems like this sometimes happen becasue the heat in the wire can't get out and this degrades the polymer.
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Best Regards, Tom Cunningham www.ExtrusionTechnicalServices.com IP: Logged |
polymerguy
Senior Member Posts: 28
From:germany
Registered: Nov 2006
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posted December 07, 2006 01:30 AM
quote:
Originally posted by Tom C:
How hot is the wire prior to extrusion?How is the product cooled? Problems like this sometimes happen becasue the heat in the wire can't get out and this degrades the polymer. Thanks Tom for your quick reply. the wire is preheated to 180°C before sintering and then it is sintered
the maximum sintering temperature is 365°C
IP: Logged |
Tom C
Moderator Posts: 852
From:Brodheadsville, PA USA
Registered: Jun 2001
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posted December 07, 2006 08:06 AM
Still if the coating is thick, and the cooling is only of the outside, then the wire can be at a high temperature for a long time. This could cause degradation, gassing and embritlement of the polymer near the wire. Things get worse as the wire gets heavyer and the coating thicker because the heat in the wire can get out.
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Best Regards, Tom Cunningham www.ExtrusionTechnicalServices.com IP: Logged |
