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RE: [MW:7353] Best way for Preheating of Bush & shaft Welding

By Materials & Welding

An induction heating system induces heat electromagnetically rather than by using a heating element to conduct heat

Induction heating chart figure 3

In induction heating, electric current flows through the coil, generating a magnetic field in the part. The rapidly changing magnetic field creates eddy currents in the part, causing heat to be generated. This is similar to the heat generated in a transformer. The coils do not heat up, so welding can be done while the coil is still attached.

 

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of Devarajan Ramasamy
Sent: Monday, October 04, 2010 4:10 PM
To: materials-welding@googlegroups.com
Subject: Re: [MW:7352] Best way for Preheating of Bush & shaft Welding

 

Yes similar.. 

On Mon, Oct 4, 2010 at 6:30 PM, Engineer Mech <mengineer010@gmail.com> wrote:

Dear Devarajan,

 

May i know induction coil heating is it same as Electrical resistance heating for PWHT,

 

Thanks

On Mon, Oct 4, 2010 at 1:18 PM, Devarajan Ramasamy <neo.devarajan@gmail.com> wrote:

For any preheating more than 150 deg C, induction coil heating is much preferred. 

 

On Mon, Oct 4, 2010 at 4:53 PM, Engineer Mech <mengineer010@gmail.com> wrote:

Dear All,

Job is Bush & Shaft welding,
Shaft is about 300 mm OD, Preheating is 220 degree celsius
By which way i can do preheating, Heating torch is enough for
preheating of this job, or Electrical resistance heating is it need to
do?
I think Heating torch is ok!
Pl clear me...

Regards
M






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