Tube sealing in tube bundle heat exchangers

A tube bundle heat exchanger comprising a generally tubular housing including a jacket tube and an extension tube extending substantially coaxially with said jacket tube, said jacket and extension tubes having adjacent open ends relatively spaced apart, sealing means including an elastic sealing tube plate mounted in the space between said jacket and extension tubes and extending transversely thereof, a first rigid tube plate mounted within said extension tube in contact with said elastic tube plate and extending substantially parallel thereto, a second rigid tube plate mounted within said jacket tube in contact with said elastic tube plate and extending substantially parallel thereto, mounting means on at least one of said jacket and extension tubes for mounting at least one of said first and second rigid tube plates for movement axially of said jacket and extension tubes toward said elastic sealing tube plate, said mounting means including abutment means extending from the inner surfaces of at least one of said jacket and extension tubes for engaging the respective surface of the axially movable rigid tube plate which is opposite the surface thereof in contact with said elastic sealing tube plate, a plurality of heat exchanger tubes extending in spaced relationship axially of said jacket and extension tubes through aligned apertures formed in said first and second rigid tube plates and said elastic sealing tube plate, one end of each of said heat exchanger tubes opening into said extension tube, tube retaining means formed on said first rigid tube plate for retaining said heat exchanger tubes within said first rigid tube plate, circumferential sleeve means extending around the adjacent spaced ends of said extension and jacket tubes and over an annular gap therebetween to enclose said elastic tube plate, said sleeve means being formed to permit relative axial movement of said jacket and extension tubes, and a plurality of force applying means connected between said jacket and extension tubes and operative to move the spaced open ends thereof toward one another to cause axial movement of said first and second rigid tube plates against opposite sides of said elastic sealing tube plate and expansion of said elastic sealing tube plate against said heat exchanger tubes and the adjacent open ends of said extension and jacket tubes to enhance the sealing of said annular gap.