Abstract: A method and a device for controlling thermal stresses in a power saw blade, especially a circular or band saw blade, during its use for any purpose, in order to assure the stability of the saw blade, by continuously measuring the temperature in two or more zones on the saw blade and determining the temperature difference between the zones; comparing the temperature difference(s) so calculated with one or more predetermined, desired temperature difference values; and using the result(s) of said comparison(s) to regulate the supply/removal of heat to/from one or more of said zones, in order thereby to maintain the/those desired temperature difference(s). The device comprising at least two temperature sensors a temperature comparator and one or more heat generators.