Re: Induction melting of steel - melting time calculation

Hi James, sorry for the late reply I don't hang out on the group these days.

I just did a ball park calculation using heat capacity of steel roughly 500J/kg/K ie. 500* 1500 * (3.5/2.2) = 1.2MJ; the 0.1 error is because I did it the calc in my head.

I (knowingly) didn't include the latent heat of fusion for the ballpark calculation. In retrospect I probably should have because it is significant. I think for iron/steel Lf = 250kJ/Kg which comes out to 250k*(3.5/2/2) = 0.4MJ. That should be added onto the 1.2MJ giving a total of 1.6MJ (45% higher than my rough estimate).


James H. wrote:
"RobS" <a@xxx> wrote in message news:43a55ee0$0$18202$afc38c87@xxxxxxxxxxxxxxxxxxxxxxx

I got a similar result to James.  You need about ~1.1MJ of energy to
melt the bar.



How did you derive the 1.1 MJ value?

James


At 100% furnace efficiency that takes about 70 seconds to
melt.  I pulled an induction furnace efficiency of 3.6% to 17% (for
aluminium) from the web - presumably for a practical design with all
factors taken into account.




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