Abstract: The present invention relates to novel dryer systems that incorporate two-stage processes for heating air for drying a traveling web. The present invention is operable within a drying system having a drying hood containing a dryer. The drying hood receives heated air through an intake and expels system air through an exhaust, a portion of which is directed into the atmosphere. The portion of system air that is maintained in the system is divided into two portions and directed into separate parallel conduits for two-stage heating that results in greater temperature uniformity and efficiency within the system. One loop includes a mixing chamber for the initial mixing of system air with the combustion products of a burner. A second loop includes an injection chamber that receives the initially mixed air and injects it into the other portion of the system air, resulting in greater temperature uniformity within the drying hood and increased operating efficiency for the entire system.

Abstract: The present invention includes a nozzle insert for use in a drying machine of the type used in paper web drying. The nozzle insert of the present invention includes at least one intake having a central portion, wherein a pair of center vanes is disposed for directing airflow. The central portion is bounded by at least one turning vane adapted for directing airflow in a lateral direction. For each turning vane, there is at least one straightening vane adapted for curtailing swirling of the airflow. The vanes are oriented at optimal angles for directing the flow of the nozzle in a lateral direction, while permitting some air to penetrate the central portion through a series of ports. The intakes are bounded by a series of insulated bulkheads, which serve to direct airflow and contain heat-loss through thermal emission.