Multitubular heat exchanger

Claim 2

In a multitubular heat exchanger comprising a shell, a heating medium inlet formed in said shell, a high temperature tube bundle and a low temperature tube bundle located within said shell and formed by a large number of U-shaped heat transfer tubes for permitting a medium to be heated to flow therethrough so that heat exchange may take place between the medium to be heated and a heating medium introduced into the interior of said shell through said heating medium inlet, and a vent tube interposed between said high temperature tube bundle and said low temperature tube bundle arranged in the longitudinal direction of said shell for removing noncondensable gas therethrough from the interior of the shell, wherein the improvement comprises: means for defining at least one laterally-closed flow passage in at least one of said tube bundles, said flow passage inducing therethrough part of the heating medium flowing between said shell and said tube bundles to an inner deep portion of said at least one tube bundle.

Claim 3

A multitubular heat exchanger as claimed in claim 1, wherein said flow passage defining means comprises at least one slit opening at the outer periphery of said at least one tube bundle and extending toward the interior of the latter tube bundle, and at least one pair of flow regulating plates arranged in said slit for defining therebetween said flow passage.

Claim 4

A multitubular heat exchanger as claimed in claim 1 or 2, wherein said flow passage extends, as viewed on a transverse sectional surface of said heat exchanger, radially inwardly from the outer periphery of said at least one tube bundle toward said vent tube.

Claim 5

A multitubular heat exchanger as claimed in claim 1 or 2, wherein said flow passage extends, as viewed on a transverse sectional surface of said heat exchanger, in a straight line from the outer periphery of said at least one tube bundle toward a position in the boundary between said two tube bundles displaced from said vent tube.

Claim 6

A multitubular heat exchanger as claimed in claim 2, wherein said flow passage defining means is provided in at least said high temperature tube bundle, and said slit and said pair of flow regulating plates extend, as viewed on a transverse sectional surface of said heat exchanger, radially inwardly from the outer periphery of the high temperature tube bundle toward the vent tube, one of said pair of flow regulating plates in the high temperature tube bundle located on the downstream side of streams of the heating medium introduced into said shell having an inner end disposed a little distance short of the inner end of the other of said pair of flow regulating plates disposed on the upstream side thereof.

Claim 7

A multitubular heat exchanger as claimed in claim 2, wherein said flow passage defining means is provided in at least said low temperature tube bundle, and said slit and said pair of flow regulating plates extend, as viewed on a transverse sectional surface of said heat exchanger, radially inwardly toward the vent tube from the outer periphery of said low temperature tube bundle, one of said pair of flow regulating plates in said low temperature tube bundle located on the downstream side of streams of the heating medium introduced into said shell having an inner end disposed a little distance short of the inner end of the other of said pair of flow regulating plates disposed on the upstream side thereof.

Claim 8

A multitubular heat exchanger as claimed in claim 2, wherein said high temperature tube bundle is located above said low temperature tube bundle in superposed relation, said flow passage defining means is provided in at least said high temperature tube bundle, and said slit and said pair of flow regulating plates extend, as viewed on a transverse sectional surface of said heat exchanger, substantially vertically downwardly into the high temperature tube bundle from the position on the outer periphery of the latter tube bundle displaced laterally from the vent tube, one of said pair of flow regulating plates in the high temperature tube bundle remote from a side wall of the shell having an inner end disposed a little distance short of the inner end of the other of said pair of flow regulating plates near the side wall of the shell.

Claim 9

A multitubular heat exchanger as claimed in claim 2, wherein said high temperature tube bundle is located above said low temperature tube bundle in superposed relation, said flow passage defining means is provided in at least said low temperature tube bundle, and said slit and said pair of flow regulating plates extend, as viewed on a transverse sectional surface of said heat exchanger, substantially vertically upwardly into the low temperature tube bundle from the position on the outer periphery of the latter tube bundle displaced laterally from the vent tube, one of said pair of flow regulating plates in the low temperature tube bundle remote from a side wall of the shell having an inner end disposed a little distance short of the inner end of the other of said pair of flow regulating plates near the side wall of the shell.

Claim 10

A multitubular heat exchanger as claim in claim 1, wherein said high temperature tube bundle is located above said low temperature tube bundle in superposed relation and said flow passage is provided in at least said high temperature tube bundle and having an inlet portion opening upwardly, and further comprising a drain separator provided at said inlet portion of said flow passage for separating drain from the heating medium flowing across said inlet portion and directed away from said flow passage, to induce the drain to flow into the flow passage.

Claim 11

A multitubular heat exchanger as claimed in claim 2, wherein said high temperature tube bundle is located above said low temperature tube bundle in superposed relation, said pair of flow regulating plates are provided in at least said high temperature tube bundle, said flow regulating plates have outer ends located at the upper portion of said high temperature tube bundle spaced from said heating medium inlet laterally toward the side wall of said shell and extending into the interior of the latter tube bundle, said outer ends of said flow regulating plates defining an inlet portion of said flow passage opening upwardly of the high temperature tube bundle; and wherein said heat exchanger further comprises a drain separator plate projecting upwardly from the outer end of one of said pair of flow regulating plates located near the side wall of said shell and being inclined inwardly toward the other of said pair of flow regulating plates, said drain separator plate separating drain from the heating medium flowing across said inlet portion of said flow passage and inducing the drain to flow into said flow passage.