Temperature conversion over a duration 1

[tonykenna]

According to ASME Section VIII Division 1, Rate of heating and cooling for P1 material is 400F/hr which they state is 222C/hr. At the risk of sounding foolish, a direct converstion of 400F shows up as 204C with my math. Why is it when you include a duration, that conversion is no longer valid?

 

[Compositepro]

Temperature change is not at all the same thing as temperature. Fahrenheit and Celsius temperature scales have different zero points and you have to account for this when converting temperature scales. With temperature differences it does not matter what the zero point of the scale is only the size of the temperature unit.

 

[tonykenna]

If I heat something from Ambient Temperature to 400F over a duration of 1 hour, that thermometer will also read 222C at that same 1 hour point as opposed to the 204C you would get from a direct conversion. Correct?

How would someeone do the math to figure that out for other temperatures?

 

[redpicker]

When you heat something from Ambient (75F) to 400F, you are not heating it 400F; you are only heating it 325F.

rp

 

[Compositepro]

So at what temperature did you start your heating process? Only if you started at O degrees F is your heating rate 400F/hour. Again, temperature change is not at all the same thing as temperature.
If you do not understand this then you do not belong here. Please go to Wikipedia and study the concepts.

 

[tonykenna]

RIGHT!! Sigh...