On Wed, 19 Sep 2018 16:40:30 -0700, wrote:

I have a small run of parts that have a #3 Morse taper on one end. At
the small end of the taper is a straight diameter that's .700 diameter
by .600 long. The material is 17-4 PH stainless. I want to harden the
small end only. To do this it must be heated to 900 degrees F and held
there for a while. I was wondering if a 2000 watt induction heater
would be up to the task. I know there are many variables but there
must be a minimum amount of power needed. Anybody know?

Yes I do. Until last July 1st when health problems forced my
retirement, I owned Tellico Induction Company Inc. Or Tnduction. We
manufactured a line of Royer-type induction heaters ranging from 1500
watts to 10kW. Our 2500 watt heater would have done the job just
fine.

I have a set of spreadsheets to compute stuff like this. Assuming
you're starting at 70 deg and ignoring Stephan-Boltzman radiative
losses and ignoring heat conducted away by the adjacent steel, it will
take approximately 260 seconds to reach 900 deg F with a 2500 watt
heater. So I'd guess about 300 seconds. Our 3500 watt unit would
reduce the time to about 190 seconds.

Normally at this point I'd go into the lab, prepare a test specimen
duplicating your taper and actually time the heat rate. Unfortunately
I've sold my lab and shop.

My only question is that if you're going to hold the small end at 900
deg for a period of time, how are you going to keep the heat away from
the heat affected zone?
John DeArmond
http://www.neon-john.com
http://www.tnduction.com
Tellico Plains, Occupied TN
See website for email address