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[MW:13987] RE: 13985] PWHT OF P91 BY INDUCTION HEATING

By Materials & Welding

Try to put metal plug dummy on both side of the joint to avoid heat losses for maintaining the temperature

Nagoor Meeran

L&T-KAPP

 

From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of sandeep monody
Sent: Saturday, March 24, 2012 5:37 PM
To: materials-welding@googlegroups.com
Subject: [MW:13985] PWHT OF P91 BY INDUCTION HEATING

 

Dear experts,

 

In my site we conducted a demonstration of PWHT on SA335 P91 material (OD-450mm X 70mm Thk) as our clients requirement and details as given below.

 

Heating/cooilng rate;-60 deg C,Holding temparature:-760deg C and holding time:-180minutes,Heating band width:-210mm and insulation band width 630mm,Heating method :-Induction heating

 

During pwht we observed a temparature difference on outside and inside of pipe more than 80 deg C.

 

Now problem is that client is not accepting this method and asking for uniform temparature in outside and inside of pipe.

 

How can i control temparature at both sides?

Is it possible a uniform temp on both side with induction heating?

 

Please give ur valueble advice in this matter.

 

 

Sandeep.

QC Engr

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