CN-122003573-A - Tube around heat exchanger deformable support system and method

Abstract

A coiled tube heat exchanger utilizing a deformable support system and a method for manufacturing a tube bundle for the coiled tube heat exchanger includes a mandrel, a first tube layer formed by wrapping one or more tubes around the mandrel, and a plurality of supports and spacers circumferentially arranged in an alternating pattern on an outer surface of the first tube layer. The second tube layer is formed by wrapping one or more tubes around the mandrel, whereby the second tube layer contacts the opposite side of the support. Applying a deforming force to the second tube layer in a direction normal to the outer surface of each support, which deforms one or more tubes forming the second tube layer to deform the outer support surface of each support.

Inventors

• A Li.aoke
• J. A. Dali
• S. C. Turnarelli
• R. Strebig
• C.R. BUTLER

Assignees

• 霍尼韦尔液化天然气有限公司

Dates

Publication Date

20260508

Application Date

20240926

Priority Date

20230929

Claims (20)

1. 1. A method of forming a tube bundle for a coiled tube heat exchanger, wherein the tube bundle comprises a plurality of tube layers, each layer comprising at least one tube, and the method comprises: (a) Providing a mandrel extending along a mandrel longitudinal axis; (b) Forming a first tube layer by wrapping at least one tube of the at least one tube around the mandrel, the at least one tube having a tube height H; (c) Placing a plurality of first layer supports and a plurality of first layer spacers on an outer tube surface of the first tube layer, each of the first layer supports having a support longitudinal axis, an inner support surface in contact with the outer tube surface, and an outer surface distal from the inner support surface, each of the plurality of first layer spacers having a spacer height S; (d) Forming a second tube layer by wrapping at least one tube of the at least one tube around the mandrel, the first tube layer, and the plurality of first layer supports, and (E) Applying at least one deforming force to the second tube layer in a direction normal to the outer support surface of each of the plurality of first layer supports, the at least one deforming force being sufficient to deform the at least one tube forming the second tube layer by at least one of the outer support surface and the inner support surface of each of the plurality of first layer supports without deforming the at least one tube forming the second tube layer.
2. 2. The method of claim 1, wherein a radial layer spacing between the first tube layer and the second tube layer is greater than the spacer height S before performing step (e) and equal to the spacer height S after performing step (e).
3. 3. The method of claim 1, the method further comprising: (f) Placing a plurality of mandrel layer supports on the mandrel prior to performing step (b) such that the mandrel layer supports are positioned between the mandrel and the first tube layer.
4. 4. The method of claim 1, wherein the application of the deforming force moves at least one of the outer support surface or the inner support surface of at least one of the plurality of first layer supports from an initial contact position to a recessed position, and wherein a distance E between the initial contact position and the recessed position is at least 5% of the tube height H.
5. 5. The method of claim 4, wherein the distance E is less than 50% of the tube height H.
6. 6. The method of claim 1, wherein the deforming force of step (e) is a result of applying tension to the second tube layer during step (d).
7. 7. The method of claim 1, wherein at least a portion of the deforming force of step (e) is applied by an external device that passes over the second tube layer during or after performing step (d).
8. 8. The method of claim 1, wherein step (b) further comprises winding the at least one first layer tube around the mandrel at a winding angle α relative to the mandrel longitudinal axis, and step (d) further comprises winding the at least one second layer tube at a winding angle α relative to the mandrel longitudinal axis.
9. 9. The method of claim 1, wherein each tube of the at least one tube has a radial compressive strength and each first layer of the plurality of first layer of supports has a support outer layer having a support outer layer radial compressive strength that is less than the radial compressive strength of the tube.
10. 10. The method of claim 8, wherein the outer support surface of each support of the plurality of first layer supports is adapted to deform via the deforming force to form a tube socket oriented at an angle corresponding to either of the winding angle a or the winding angle-a during performance of step (b).
11. 11. The method of claim 1, wherein each first layer support of the plurality of first layer supports comprises a non-deformable spacer portion that is substantially non-deformable during performance of step (e).
12. 12. The method of claim 1, wherein step (b) further comprises disposing the plurality of first layer supports and the plurality of first layer spacers in a circumferentially alternating arrangement on the outer tube surface of the first tube layer.
13. 13. The method of claim 1, the method further comprising: (g) Applying a pre-wrap force to each of the plurality of first layer supports prior to performing step (d), the pre-wrap force causing each of the plurality of first layer supports to deform only on the inner support surface.
14. 14. The method of claim 1, further comprising forming one or more additional tube layers in the tube bundle by repeating steps (c) through (e) for each additional tube layer in the tube bundle.
15. 15. The method of claim 1, wherein each of the plurality of first layer supports placed in step (c) is also one of the plurality of first layer spacers.
16. 16. The method of claim 15, wherein each first layer support of the plurality of first layer supports comprises an inner layer and at least one outer layer, a maximum inner layer radial compressive strength of the inner layer being greater than an outer layer maximum radial compressive strength of each outer layer of the at least one outer layer.
17. 17. A method of forming a tube bundle for a coiled tube heat exchanger, wherein the tube bundle comprises a plurality of tube layers, each layer comprising at least one tube, and the method comprises: (a) Providing a mandrel extending along a mandrel longitudinal axis; (b) Forming a first tube layer by wrapping at least one tube of the at least one tube around the mandrel, the at least one tube having a tube height H; (c) Placing a plurality of first layer supports and a plurality of first layer spacers in a circumferentially alternating arrangement on an outer tube surface of the first tube layer, each of the plurality of first layer supports having an undeformed support height H2, and each of the plurality of first layer spacers having a spacer height H1; (d) Forming a second tube layer by wrapping at least one tube of the at least one tube around the mandrel, the first tube layer, and the plurality of first layer supports, and (E) Applying at least one deforming force to the second tube layer, the at least one deforming force being sufficient to deform each first layer support of the plurality of first layer supports without deforming the at least one tube forming the second tube layer; Wherein the first tube layer and the second tube layer have an initial inter-layer distance at each of the plurality of first layer supports before performing step (e), and a final inter-layer distance at each of the plurality of first layer supports after performing step (e), the final inter-layer distance being less than the initial inter-layer distance.
18. 18. The method of claim 17, wherein each support of the plurality of first layer supports comprises a plurality of individual support structures such that each support of the plurality of first layer supports is discontinuous along an axial direction of the tube bundle.
19. 19. The method of claim 17, wherein the final layer spacing is substantially equal to the spacer height H1.
20. 20. The method of claim 17, wherein the initial layer spacing is substantially equal to the undeformed support height H2.

Description

Tube around heat exchanger deformable support system and method Cross Reference to Related Applications The present application claims priority from U.S. non-provisional application No. 18/477,644, filed on 9/29 of 2023, and incorporated by reference. Background The present application relates to coiled tube heat exchangers (CWHEs), and more particularly to a method and system for supporting individual tube layers of a CWHE tube bundle. CWHE is often used in the process industry for heating or cooling fluid streams at high heat transfer rates where large heat transfer areas are required. CWHE utilizes a tube bundle constructed of a plurality of long tubes that are helically wound around an axially central core called a mandrel. The tube bundle is enclosed within a shroud. The tube bundle and mandrel are sealed within a housing that provides a pressure boundary. The mandrel, housing and shroud provide structure for the CWHE and allow connectivity of other operating components. Multiple long tubes are wound to form one or more helical structures having different diameters. This forms a tube bundle comprising a plurality of tube layers formed in a radial direction, wherein the diameter of each outwardly positioned tube layer is increased relative to the previous inner tube layer. Adjacent tube layers are typically maintained at a desired separation distance (also referred to as the layer spacing) from each other by axial spacers. Such spacers are typically solid rods or wires. The spacers typically have a circular cross-sectional shape, but may have different cross-sectional geometries (e.g., oval, square, rectangular, etc.). Each tube may be supported by supports that may be circumferentially spaced between each tube layer and may be positioned parallel to the mandrel. In other implementations, the spacers may be positioned in a spiral arrangement and/or have non-uniform spacing. Each support may include preformed recesses or other structures that hold or cradle the tubes, thereby holding the tubes in a desired position. One disadvantage of preformed supports is that each preformed support can only be used with tube bundles having a particular tube bundle geometry, including the number and size (diameter) of the tubes, the desired tube layer spacing, and the tube layer wrap angle. This means that a different preformed support has to be provided for each CWHE with a different tube bundle geometry, which may lead to higher production times and costs. Accordingly, there is a need for an improved system and method for spacing and supporting tube layers of a tube bundle of a CWHE, wherein each support is not limited to use with a particular tube bundle geometry. Disclosure of Invention The disclosed embodiments address the needs in the art by providing a deformable support structure that is formed into a final desired configuration during the tube winding step of CWHE construction and assembly. The structure of the deformable support is not limited to use in a particular CWHE configuration and may have a common starting structure regardless of the final configuration of the CWHE, as the final structure of the deformable support is formed during the construction of the CWHE. A deformable support structure having a single design can be manufactured to support the individual tube layers in a manner that achieves the radial and axial stiffness required and used throughout the CWHE tube bundle. The deformable support members may be used to support the tube bundle system in a non-operating or operating condition. In some configurations, the deformable support may optionally have non-deformable portions that can be used as spacers, and thus replace the need for separate spacers. During a tube winding operation, a deformable support is positioned between the various tube layers. During initial construction of the CWHE, the first deformable support structure is positioned in contact with and attached to the mandrel prior to winding the first tube layer. The first tube layer is then wrapped around the mandrel such that the first deformable support is positioned between the mandrel and the first tube layer. The first deformable support structure may include a non-deformable portion that may act as a spacer such that a winding operation of the first tube layer around the mandrel will deform a portion of the deformable support, leaving the non-deformable portion unchanged, such that the non-deformable portion may provide a desired spacing between the first tube layer and the mandrel. Alternatively, where the deformable support structure does not include non-deformable portions, one or more separate non-deformable spacers may also be positioned between the mandrel and the first tube layer to provide a desired spacing between the first tube layer and the mandrel. After the winding of the first tube layer is completed, a series of additional deformable supports are positioned on the completed first tube layer. When winding a subs