Abstract: A rotary cylinder for heat-treating a web bearing against its outer surface is heated by an internal stationary assembly of IR burner modules that heat lengthwise distributed annular bands of the cylinder, the burners having air-fuel mixture supplies that are regulated by cross-machine sensing of the web for controlling the web's cross-machine profile characteristics, the cylinder being part of a machine comprising a succession of like IR-burner-heated cylinders operated at respective optimal temperatures. The assembly of IR burners is removable from an end of its cylinder for service or modification. The interior of the stationary IR burner structure is protected against undue heat build-up.

Abstract: A web to be heat-treated bears against a rotary cylinder containing a stationary complement of IR burner modules in an assembly that is axially removable from the cylinder. The IR burner complement extends all along--but only partway around--the cylinder, leaving an arcuate gap. An exhaust manifold in the gap has a configuration that precludes localized accumulation of high-temperature exhaust. The cylinder is heated primarily by radiant transfer from the IR burner modules and from heat shields, which fill any arcuate spaces not occupied by either the exhaust manifold or the IR burners. The arcuate extent of the IR burners is proportioned for developing prescribed heat output when the air/fuel mixture is supplied at maximum rate. The cylinder heat output may be reduced over a wide range, notably when the cylinder speed is adjusted during start-up and slow-down of operations. The IR burner modules heat annular bands around the cylinder to develop a temperature profile along the cylinder, i.e., across the web.

Abstract: The disclosed cylinder for heat-treating a web is rotatable about a horizontal axis and is heated by one or multiple stationary infrared burners that extend all along the length of the cylinder, but which are limited to an arcuate extent, establishing a maximum cylinder heat output when the burner(s) is (are) supplied with air-fuel mixture at their maximum rate. Reduction of the air-fuel supply rate over a wide range allows the cylinder heat output to be reduced as the web processing speed is reduced. When the burner is divided into segments, the temperature profile along the cylinder; i.e., across the width of the web, can be regulated to adjust the moisture profile of the web. An exhaust manifold within and along the cylinder is configured so as to avoid any local accumulation of high-temperature exhaust.