Above 600°F, the rate of heating shall not be more
than 400°F per hour divided by the maximum metal thickness
of the thicker part, in inches, but in no case more than
400°F per hour. Above 315°C, the rate of heating in °C/hr
shall not exceed 5600 divided by the maximum metal
thickness, in millimeters, but not more than 220°C/hr.
what does 5600 mean? is it the rate of heating? the unit?