Miller Electric IH - Manual (Page 28)

OM-203 185 Page 24
Step to
600 ° F as
fast as
possible
Ramp to 800 ° F
@ 400 ° /hr
SEG.n
1
tYPE
StEP
tGt
600
(step)
(deg)
SEG.n
2
tYPE
rmP.r
tGt
800
(ramp rate)
SEG.n
4
tYPE
dwEl
dur
1.0
(soak)
(in hrs)
0
200
400
600
800
1000
1200
1400
0.0 1.0 2.0 3.0 4.0 5.0 6.0
Time (hours)
Degrees F
Example Multi−Step Stress Relief Profile
SEG.n
5
tYPE
rmP.r
tGt
800
(ramp rate)
rAtE
400
(deg)
(deg/ hr)
rAtE
200
(deg)
(deg/hr)
Dwell @ 1250 ° F
for 1 hour
Ramp to 1250 ° F
@ 200 ° /hr
7.0
SEG.n
6
tYPE
rmP.r
tGt
600
(ramp rate)
Free fall to
ambient
SEG.n
7
tYPE
End
End.t
S OP
(end)
(sets output to 0)
rAtE
400
(deg)
(deg/hr)
Ramp to 600 ° F
@ 400 ° /hr
Ramp to 800 ° F
@ 200 ° /hr
SEG.n
3
tYPE
rmP.r
tGt
1250
(ramp rate)
rAtE
200
(deg)
(deg/ hr)
.
*On small diameter pipe, it may be necessary to reduce the
output of the power source to achieve a “reasonable rate”
in Segment 1; thereafter, the program controls the rate of
temperature rise and the output power may be increased
to full if desired. To reduce output power, turn power source
output knob to desired setting.
Figure 6-3. Setting A Complex Stress Relief Profile With Multiple Temperature Rise/Cool Rates
Using Example Parameters