Patent ID: 6883347

Claim:
A heat exchanger, comprising: a) a shell having a first fluid inlet and a first fluid outlet, and having first and second ends; b) a plurality of tubes located in the shell and extending horizontally between the first and second shell ends; c) a tube sheet located at each of the first and second shell ends, the tube sheet allowing the tubes to pass therethrough; d) each of the first and second shell ends having a bonnet located thereon, with at least one of the bonnets having a second fluid inlet and a second fluid outlet; e) a wall located in the bonnet with the second fluid inlet, the wall forming a chamber, which chamber allows communication between the second fluid inlet and at least some of the tubes that provide an exit from the chamber, the wall being separated from the adjacent tube sheet by a distance so as to form a cross-sectional area of the chamber that is substantially equal to the cross-sectional area of the tubes exiting the chamber.