Shell and tube heat exchanger

Claim 2

A heat exchanger comprising: a) a generally tubular shell (12) having first inlet means (54) and first outlet means`(62) for respectively permitting the ingress and egress of a first heat exchange liquid and'second inlet means (18) and second outlet means (20) for respectively permitting the ingress and egress of a second exchange fluid; b) a pair of end members (14, 16) coupled to the axially-opposed ends of the shell to define an internal chamber therein; c) a plurality of tube members (75) extending within the chamber; d) means for coupling the first heat exchange fluid into at least one of the tube members; e) first means for sealing the intermediate region of the chamber from the non-intermediate regions while permitting the non-intermediate regions to communicate via the tube members; f) means (75) for establishing a flow of the second fluid through the chamber; and g) end baffle means co-operative with the end members for forming a plurality of fluid flow continuums to provide a multi-pass flow of first fluid through the chamber between the non-intermediate regions.

Claim 3

The heat exchanger of Claim 1 wherein axially-extending baffle means (74) are provided for partitioning an intermediate region of the chamber into a plurality of axially extending sub-chambers respectively occupied by a number of the tube members, and said flow establishing means provide for a multipass flow of the second fluid through the chamber via successive partitioned sub-chambers, such that the flow of first fluid in the tube members is in opposition to the flow of the second fluid through that partitioned sub-chamber and a full counterflow is provided.

Claim 4

The heat exchanger of Claim 2 wherein the axially-extending chamber partitioning baffle means includes a plurality of generally axially-extending surface members (76-84) projecting generally radially outward from a central hub area to define a plurality of axially extending sub-chambers each enclosing a nest of heat exchange tubes.

Claim 5

The heat exchanger of Claim 3 wherein the baffle means includes a generally axially-extending peripheral wall sealingly joining the radially outward of the surface members.

Claim 6

The heat exchanger of Claim 4 wherein the baffle means includes a plurality of interlocking baffle members, each comprising an axially-extending radial arm and a circumferential arm corresponding generally to a segment of the peripheral wall member projecting from the outer end of the radial arm, said baffle member including means for sealingly engaging adjacent baffle members, to define the axially extending sub-chambers.

Claim 7

The heat exchanger of Claim 5 wherein the means for sealingly engaging adjacent baffle members includes an axial extending groove formed at one end of the circumferential arm and a complimentary shaped axially-extending protrusion formed at the other end of the circumferential arm, each positioned to fit within the corresponding other of an adjacent baffle member.

Claim 8

The heat exchanger of Claim 6 wherein the inner end of the tube sheet is adapted for britting contact with the inner end of the adjacent tube sheet and the surface members are sized radially for abritting contact under compression when the baffle assembly is in the shell.

Claim 9

The heat exchanger of Claim 4 including means for defining a space between the wall of the chamber and the circumferential arms of the assembled baffle members to provide an annular chamber which is filled with the second exchange fluid to act as a thermal buffer to reduce temperature differential in the outer shell of the chamber.

Claim 10

The heat exchanger of Claim 8 including means for coupling the second heat exchange liquid from the second outlet means into the spece between the chamber wall and the peripheral wall member.

Claim 11

The. heat exchanger of Claim 1 wherein the end baffle means includes a generally annular member circumventing a plurality of vane members, the vane members contacting the generally annular member at least once and extending at least partially across the internal diameter of the annulus, the vane members co-operating with an end member to define a fluid flow continuum between the ends of adjacent tubes.

Claim 12

The heat exchanger of Claim 10 wherein the divider members extend generally radially from a generally central hole to generally circumferentially separated regions of the annular member.

Claim 13

A heat exchanger comprising: a) a #enerally tubular shell having first inlet means and first outlet means for respectively permitting the ingress-and egress of a first heat exchange liquid and second -inlet means and second outlet means for respectively permitting the ingress and egress of a second exchange fluid; b) a pair of end members coupled to the axially-opposed ends of the shell to define an internal chamber therein; c) a plurality of multi-walled tubes extending within the chamber, with the ends of the inner tube of each multi-walled tube projecting beyond the end or ends of the outer tubeor tubes and with all tubes being in thermal contact and defining a'generally axially extending interjacent gap between adjacent tubes; d) means for coupling the first heat exchange fluid into the inner tube of the multi-walled tube; e) means for directing the second heat exchange fluig through the chamber external to the outer tube of the multi-walled tube; f) first means for sealing the intermediate region of the chamber from the non-intermediate regions while permitting the non-intermediate regions to communicate via the inner tube of each multi-walled tube; g) a housing including second means for sealingly engaging the periphery of at least one of the projecting ends of the inner tube to define a region between the first and second sealing means in communication with the interjacent gap or gaps; and h) the housing including vent means for conducting fluid egressing from the gap out of the region.

Claim 14

A heat exchanger comprising: a) a #enerally tubular shell having first inlet means and first outlet means for respectively permitting the ingress-and egress of a first heat exchange liquid and second -inlet means and second outlet means for respectively permitting the ingress and egress of a second exchange fluid; b) a pair of end members coupled to the axially-opposed ends of the shell to define an internal chamber therein; c) a plurality of multi-walled tubes extending within the chamber, with the ends of the inner tube of each multi-walled tube projecting beyond the end or ends of the outer tubeor tubes and with all tubes being in thermal contact and defining a'generally axially extending interjacent gap between adjacent tubes; d) means for coupling the first heat exchange fluid into the inner tube of the multi-walled tube; e) means for directing the second heat exchange fluig through the chamber external to the outer tube of the multi-walled tube; f) first means for sealing the intermediate region of the chamber from the non-intermediate regions while permitting the non-intermediate regions to communicate via the inner tube of each multi-walled tube; g) a housing including second means for sealingly engaging the periphery of at least one of the projecting ends of the inner tube to define a region between the first and second sealing means in communication with the interjacent gap or gaps; and h) the housing including vent means for conducting fluid egressing from the gap out of the region.

Claim 15

The heat exchanger of Claim 12 wherein the first and second sealing means are positioned to accommodate axial movement of the tube pair while maintaining the gap in the region.

Claim 16

A heat exchanger comprising: a) a chamber having inlet means and outlet means for respectively permitting the ingress and egress of a heat exchange fluid; b) end members defining end chambers at each end of the main chamber having inlet means and outlet means for respectively permitting the ingress and egress of a heat exchange fluid; c) a plurality of multi-walled tubes passing through said main chamber and in communication with said end chambers, with the first heat exchange fluid connected to pass through said tubes and the second heat exchange fluid to pass through the main chamber; d) sealing means to sealably connect the inner tube of the multi-walled tube to the end chambers and to sealably connect the outer tube of the multi-walled tube to the main chamber; e) expansion means to allow the tubes to expand while preserving the sealing contact with the tubes; f) a venting chamber between the sealable contact with the inner tube and the scalable contact with the outer tube to receive any fluid flow passing between the walls of the multi-walled tube or escaping past the sealing means.

Claim 17

A heat exchanger comprising: a) a chamber having inlet means and outlet means for respectively permitting the ingress and egress of a heat exchange fluid; b) end members defining end chambers at each end of the main chamber having inlet means and outlet means for respectively permitting the ingress and egress of a heat exchange fluid; c) a plurality of multi-walled tubes passing through said main chamber and in communication with said end chambers, with the first heat exchange fluid connected to pass through said tubes and the second heat exchange fluid to pass through the main chamber; d) sealing means to sealably connect the inner tube of the multi-walled tube to the end chambers and to sealably connect the outer tube of the multi-walled tube to the main chamber; e) expansion means to allow the tubes to expand while preserving the sealing contact with the tubes; f) a venting chamber between the sealable contact with the inner tube and the scalable contact with the outer tube to receive any fluid flow passing between the walls of the multi-walled tube or escaping past the sealing means.

Claim 18

A heat exchanger of Claim 14: a) where said end members include a tube sheet at the end of the main chamber with the tube sheet having a plurality of apertures to allow the multi-walled tubes to pass there through; b) a center flange spaced from the tube sheet by an annular spacer; c) said center flange having a plurality of apertures corresponding to the pattern of aperture through the tube sheet to receive the end of the inner tube; d) with said central flange forming one surface of the end chambers; and e) with the sealing means and expansion means contacting the multi-walled tube between the tube sheet and central flange.

Claim 19

A heat exchanger as claimed in Claim 15 wherein one end only of the multi-walled tube is sealed to allow axial expansion of the tube.

Claim 20

A heat exchanger as claimed in Claim 15 wherein the sealing means include a bush with an axially stopped bore having a first part to receive the outer tube of the multi-walled tube and a second part to receive the inner tube of the multi-walled tube with suitable sealing means forming a sealable contact between the bush and the respective walls of the multi-walled tube.

Claim 21

A heat exchanger as claimed in Claim 17 where the sealing is achieved at one end by expanding the walls of the multi-walled tube into the bore of the bush and at the other end by the provision of sealing "0" rings.

Claim 22

A heat exchanger as claimed in Claim 18 where the multi-walled tube is an enhanced surface tube having a spiral groove to allow venting.

Claim 23

A heat exchanger as claimed in Claim 19 where the spiraled multi-walled vented tube is vented to atmosphere through the venting chamber at the end of the tube axially expandable through the sealing means.