A convection module is a single heating unit in a reflow system where heat transfer is effected through circulating hot air or nitrogen. The design of the modules is such that the fan circulating the medium always aspirates only that air or nitrogen it has previously expelled. In a well-designed system, the air circulating in a specific module does not affect, nor does it get affected from, the directly preceding or following module.
Direct-fired heaters work by using fuel, such as gas or oil, to heat the air. An open flame is it inside the unit which warms incoming air before it is exhausted, delivering a vast amount of heat output quickly.
A HRSG (heat recovery steam generator) is an energy recoveryheat exchanger that recovers heat from a hot gas stream. It produces steam that can be used in a process (cogeneration) or used to drive a steam turbine (combined cycle).
A package boiler is a factory-made boiler and is available in a range of standard designs. Package boilers are used for heating and act as a steam generator for small power purposes such as self-powered industrial plants.