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[MW:3836] RE: 3825] DC CC

By Materials & Welding
Following from AWS Welding Handbook, Volume 2, pg. 196
 
AC, DC - CC or DC - CV can be used for submerged arc welding -
 
:  "A constant voltage power supply is self regulating, so it can be used with a constant speed wire feeder.  No voltage or current sensing is required to maintain a stable arc, so very simple wire feed speed controls may be used.  The wire feed speed and wire diameter control the arc current and the power supply controls the arc voltage."
 
:"  Constant current sources are not self regulating so they must be used with a voltage sensing variable wire feed speed control.  This typd of control adusets the wire feed speed in response to changes in arc voltage.  The voltage is nonitored to maintain a constant arc length.  With this system the arc voltage is dependent upon the wire feed seed and diameter.  The power source controls the current.  Because voltage sensing variable wire feed speed controls are more complex, they are also more expensive than the simple constant wire feed speed controls that may bve used with CV systems."
 
It is just less expensive to use CV and I would imagine simplicity also means less prone to failure/problems.
 
John A. Henning
Senior Welding Engineer
 
 
 
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of ganesh kumar
Sent: Sunday, December 13, 2009 7:10 AM
To: materials-welding@googlegroups.com
Subject: [MW:3825] DC CC

Hello friends
      I had an doubt regarding the power source. Why DC-CC power source is not preferred in SAW process.
Due the voltage variations or any other specific reasons
kindly reply me if any one knows  the answer

--
Ganeshkumar M

Mobile: 9442510888

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