There is a number of different styles of furnaces which are designed to heat treat ferrous metals. These include batch systems (Top Hat & Bogie) and continuous (Continuous Strip). The former types are usually employed in foundries to heat treat castings to produce the correct material hardness or fabrication shops to stress relieve welded items. The latter is a continuous process which anneals steel strip after rolling, to achieve the required malleability. Burners with good turn-down characteristics are required for this application, as the temperature has to be accurately controlled during the ramp-up, soak and cooling periods of the cycle. This is achieved in the continuous system by controlling the temperatures in the various zones through which the material passes. The control system for these furnaces is equipped with temperature recording devices, so that a record of the temperatures to which the material has been subjected during heat treatment can be supplied to the customer for the QA data pack.