Abstract: A heat exchange system includes a shell having an interior with an inlet and an outlet wherein a first fluid circuit is defined from the inlet, through a heat exchange volume within the interior of the shell, to the outlet. A tubesheet is mounted within the shell dividing between the heat exchange volume and a plenum of a second fluid circuit within the interior of the shell. A set of tubes extends through the heat exchange volume, a respective interior passage of each tube being in fluid communication with the plenum through a respective opening though the tubesheet. The second fluid circuit includes the plenum and interior passages of the tubes. A spray nozzle is mounted in the plenum of the second fluid circuit with a spray outlet directed toward the tubesheet for cleaning the tubesheet with a submerged impingement jet issued from the spray nozzle.

Abstract: A heat exchanger includes a shell. A tubesheet is mounted to the shell. A plurality of tubes extend from the tubesheet and into the shell for heat exchange between a first fluid within the tubes and a second fluid in the shell outside the tubes. The tubesheet divides an interior of the shell into a heat exchange chamber where the tubes can exchange heat with the second fluid, an inlet-outlet chamber for the first fluid to enter and exit the tubes. A breech lock locks the tubesheet within the shell. A bi-directionally self-energizing gasket is seated between the tubesheet and the shell to seal the heat exchange chamber from the inlet-outlet chamber. The gasket is configured to be self-energizing to seal regardless of whether there is a higher pressure in the heat exchange chamber or in the inlet-outlet chamber.