Development Of Cover Plate Type High Pressure Air Cooler With Composite Diaphragm Seal

The conventional high pressure air cooler with plug and air manifold seal has the disadvantages of easy leakage, sealing reliability, poor economy, difficult inspection and maintenance and so on. The composite diaphragm seal used for high pressure shell and tube heat exchanger was employed for tube chamber shell of high pressure air cooler in the present work. Such a scheme was numerically analyzed to improve even stressed rectangular cross section, finally designed rectangular diaphragm seal. In order to verify the rationality of the design, we made a test prototype. During the manufacture of a prototype, a special welding groove was designed for tube chamber shell, furthermore, the surfacing welding process was proposed for nickel base alloy Incoloy825. A special welding-machine for high pressure air cooler solved the problem of welding in narrow confined space. Different methods were adapted to control welding deformation of tube chamber shell, constituting series of key manufacturing technology of rectangular thick-wall vessel. The prototype was manufactured successfully. In the end the hydrostatic test and stress test justified the sealing reliability and relative design parameters of composite diaphragm seal.