Tube and plate heat exchanger

Abstract

The invention as disclosed in the following specification, relates to a heat exchanger, having tubes fitted into plates, that exchange heat from a gas passing thereover to fluids passing through the tubes. The heat exchanger is particularly adaptable to boilers having fire tubes and other types of boilers wherein the heat applied to the tubes is circulated and then exhausted. Prior to exhaust, the heated gas is passed over the plates in a duct. The tubes in the plates are used to pick up the heat from the exhaust gases by means of the feed water passing through the tubes, or the tubes can be used to directly heat other fluids, such as oil and service hot water. A damper is placed over the normal exhaust gas flue in conjunction with a second damper or duct control system whereby an exhaust fan on the downstream side of the heat exchanger duct provides a constant draw to allow the boiler to operate within its normal pressure ranges. An optimum exchange relationship between the tubes and the plates effectuates the proper heat transfer for the respective flow rates and temperature involved by means of employing a specially configured tube pitch within the plates. The exchanger is controlled by a series of electrical controls for providing adequate exhaust damping and flow rates.

Dependencies are inferred from the claim text.