Heat exchanger with elastic element

Abstract

A heat exchanger for indirect heat exchange between a first fluid and a second fluid, with a shell surrounding a shell space for receiving the first fluid, a tube bundle having a plurality of tubes arranged in the shell space for receiving the second fluid, the tubes arranged in a number of tube layers, and a jacket arranged in the shell space and enclosing an outermost tube layer in the radial direction of the tube bundle. An intermediate space is formed between the tube bundle and the jacket surrounds the tube bundle. At least one elastic element is arranged with a first region between neighboring tube portions in the outermost tube layer and a second region that protrudes out of the outermost tube layer and abuts an inner side of the jacket (3) that is facing the tube bundle or connects the elastic element to the jacket.

Claims

1. A heat exchanger for indirect heat exchange between a first fluid and a second fluid, with a shell, which surrounds a shell space for receiving the first fluid, a tube bundle comprising a plurality of tubes arranged in the shell space and intended for receiving the second fluid, the tubes being coiled in a number of tube layers around a core tube of the tube bundle and a jacket, which is arranged in the shell space and encloses an outermost tube layer of the tube bundle in the radial direction of the tube bundle, so that between the tube bundle and that jacket there is formed an intermediate space surrounding the tube bundle, characterized in that at least one elastic element is arranged with a first region between neighboring tube portions in the outermost tube layer, the at least one elastic element having a second region, which protrudes out of the outermost tube layer and is intended for abutment against an inner side of the jacket that is facing the tube bundle and/or is designed for connecting the elastic element to the jacket.

2. The heat exchanger as claimed in claim 1, characterized in that the core tube is made to extend along a longitudinal axis such that a radial direction is oriented perpendicularly to the longitudinal axis.

3. The heat exchanger as claimed in claim 2, characterized in that the heat exchanger has at least one spacing element between the outermost tube layer and the tube layer neighboring in the radial direction of the tube bundle, the at least one elastic element being fixed to the at least one spacing element and/or abutting against the at least one spacing element, in particular further spacing elements being provided between tube layers neighboring in the radial direction, these further spacing elements being arranged under the at least one spacing element to support the individual tube layers in the radial direction of the tube bundle.

4. The heat exchanger as claimed in claim 2, characterized in that the at least one elastic element extends longitudinally in the outermost tube layer.

5. The heat exchanger as claimed in claim 4, wherein the at least one elastic element is a plurality of elastic elements spaced around the core tube.

6. The heat exchanger as claimed in claim 5, wherein the plurality of elastic elements are helically spaced around the core tube.

7. The heat exchanger as claimed in claim 2, characterized in that the at least one elastic element is designed as a spring element.

8. The heat exchanger as claimed in claim 7, wherein the spring element is a leaf spring.

9. The heat exchanger as claimed in claim 1, characterized in that the at least one elastic element has two legs, which are connected by way of a base and each has an end region those end regions belonging to the second region and abutting against the inner side of the jacket, in particular the legs diverging from the base, which belongs to the first region, and in particular the elastic element being fixed to that at least one spacing element by way of the base.

10. The heat exchanger as claimed in claim 1, characterized in that the at least one elastic element is formed in a spherical or cylindrical manner.

11. The heat exchanger as claimed in claim 1, characterized in that the at least one elastic element comprises a metal or a plastic.

12. The heat exchanger as claimed in claim 11, wherein the at least one elastic element is comprised of high-grade steel.

13. The heat exchanger as claimed in claim 11, wherein the at least one elastic element is comprised of PTFE.

14. The heat exchanger as claimed claim 1, characterized in that a plurality of elastic elements are provided, respectively arranged with a first region between neighboring tube portions in the outermost tube layer, the respective elastic element having a second region, which protrudes out of the outermost tube layer and is intended for abutment against an inner side of the jacket that is facing the tube bundle and/or is designed for connection to the jacket.

15. The heat exchanger as claimed in claim 14, wherein a number of elastic elements are arranged one over the other along the longitudinal axis.

16. The use of a heat exchanger for indirect heat exchange between a first fluid and a second fluid, the heat exchanger having a shell, which surrounds a shell space for receiving the first fluid, a tube bundle comprising a plurality of tubes arranged in the shell space and intended for receiving the second fluid, the tubes being coiled in a number of tube layers around a core tube of the tube bundle and a jacket which is arranged in the shell space and encloses an outermost tube layer of the tube bundle in the radial direction of the tube bundle, so that between the tube bundle and the jacket there is formed an intermediate space surrounding the tube bundle, the heat exchanger further having at least one elastic element arranged with a first region between neighboring tube portions in the outermost tube layer, the at least one elastic element having a second region, which protrudes out of the outermost tube layer and is intended for abutment against an inner side of the jacket that is facing the tube bundle or is designed for connecting the elastic element to the jacket; wherein the first fluid is a refrigerant stream and the second fluid is a hydrocarbon-containing stream.

17. The heat exchanger as claimed in claim 16, wherein the hydrocarbon-containing stream is natural gas.

Description

(1) Further details and advantages of the invention are to be explained by the following description of figures of an exemplary embodiment on the basis of the figures, in which:

(2) FIG. 1 shows a sectional view in the form of a detail of a heat exchanger according to the invention;

(3) FIG. 2 shows a partially sectioned, perspective view of a helically coiled heat exchanger with elastic elements according to the invention; and

(4) FIG. 3 shows a cross section of an embodiment of an elastic element according to the invention.

(5) FIG. 1 shows in conjunction with FIG. 2 a heat exchanger 1 according to the invention with a plurality of elastic elements 5.

(6) The heat exchanger 1 is designed for indirect heat exchange between a first fluid and a second fluid and has a shell 10, which surrounds a shell space M for receiving the first fluid, which can be introduced by way of an inlet stub 101 on the shell 10 into the shell space M and can be extracted again from the shell space M by way of a corresponding outlet stub 102 on the shell 10.

(7) In this case, the shell 10 extends along a longitudinal axis L, which runs along the vertical with respect to a state of the heat exchanger 1 arranged as intended. Also arranged in the shell space M is a tube bundle 2 with a plurality of tubes 20 tor receiving the second fluid. In this case, the tubes 20 are coiled helically around a core tube 21 in a number of tube layers 200, 201 (for the sake of overall clarity, only the outermost tube layer 200 and the tube layer 201 located thereunder are represented in FIG. 1), the core tube 21 likewise extending along the longitudinal axis L and being arranged concentrically in the shell space M. A number of tubes 20 are respectively grouped together in a tube sheet 104, it being possible for the second fluid to be introduced by way of inlet stub 103 on the shell 10 into those tubes 20 and extracted again from the tubes 20 by way of outlet stub 105. Consequently, heat can be exchanged indirectly between the two fluids, these fluids preferably being carried through the heat exchanger 1 in counterflow.

(8) The shell 10 and the core tube 21 are of a cylindrical configuration, at least in certain portions, so that the longitudinal axis L forms a cylinder axis of the shell 10 and of the core tube 21 running concentrically therein. Also arranged in the shell space M is a jacket 3, which encloses the tube bundle 2, so that between the tube bundle 2 and that jacket 3 there is formed an intermediate space 4 surrounding the tube bundle 2. The jacket 3 serves the purpose of suppressing as far as possible a bypass flow of the first fluid, which is carried in the shell space M and to which the tube bundle 2 is subjected, past the tube bundle 2. The first fluid is therefore carried in the shell space M in the region of the shell space M that is surrounded by the jacket 3.

(9) Furthermore, the individual tube layers 200, 201 are supported (in particular when there is horizontal mounting of the tube bundle 2) on one another or on the core tube 21 by way of spacing elements 61, 6 made to extend along the longitudinal axis L, a number of spacing elements 61, 6 being respectively arranged one over the other in the radial direction R of the tube bundle 2.

(10) For decoupling heat-induced stresses/movements of the jacket 3 and the tubes 20 or tube bundle 2 with respect to one another, a number of elastic elements 5 are provided (in FIG. 2, three such elements 5 are shown by way of example), respectively integrated in the outermost tube layer 200, the elastic elements 5 preferably being distributed substantially uniformly over the first tube layer 200. In this case, the elastic elements 5 are respectively arranged with a first region 50a between tube portions 200, 200 of the outermost tube layer 200 that are neighboring along the longitudinal axis L, a second region 50b of the respective elastic element 5, which serves for abutment against an inner side of the jacket 3 that is facing the tube bundle 2 (or for the connection to the jacket 3), respectively protruding out of the outermost tube layer 200 in the radial direction R of the tube bundle 2 or of the core tube 21 in the direction of the jacket 3.

(11) The elastic elements 5 are in this case preferably respectively fixed to an outermost spacing element 61 in the radial direction R, in particular by way of a welded connection, and abut against the inner side of the jacket 3 in a sliding manner by way of the respective second region 50b. Other ways of fastening to the jacket 3 and/or to the respective spacing element 61 are likewise possible (see above).

(12) The outermost tube layer 200 is at a distance D from the inner side of the jacket 3 along the radial direction R (with respect to a non-operational state) that lies in particular in a range from 2 mm to 10 mm and allows the usually occurring heat-induced movements of the jacket 3 and the tube bundle 2 with respect to one another during the operation of the heat exchanger 1.

(13) The arrangement of the elastic elements 5 between the inner side of the jacket 3 and the respective outermost spacing element 61 allows sufficient decoupling of the outermost tube layer 200 or the tube bundle 2 on the one hand and the jacket 3 on the other hand, which makes a reduction in heat-induced stresses possible and at the same time keeps the thickness of the intermediate space 4 as small as possible.

(14) FIG. 3 shows a further embodiment of an elastic element 5 according to the invention, which may be used for example instead of the elastic element 5 in the case of a heat exchanger 1 according to FIG. 2. According to FIG. 3, the elastic element 5 has two legs 52, 53, which are formed integrally with one another by way of a curved or rounded base 51 and each have an end region 52a, 53a, those end regions 52a, 53a respectively forming a convex abutting surface for abutment against the inner side 3a of the jacket 3. In this case, the legs 52, 53 diverge from the base 51, by way of which they are fixed to the spacing layer 61 (for example by a welded connection or clamping between the jacket 3 and the spacing element 61), in the direction of the jacket 3. The legs 51, 52 may thereby form an included angle W of for example 40. The thickness of the legs 52, 53 may be between 0.3 mm and 0.5 mm, in particular 0.4 mm.

(15) The base 51 of the elastic element 5 is therefore arranged between neighboring tube portions 200, 200 of the outermost tube layer 200 or in the outermost tube layer 200 and belongs to the first region 50a of the elastic element 5, while those end regions 52a, 53a of the legs 52, 53 belong to the protruding second region 50b of the elastic element 5. The elastic element 5 may have a height H in the radial direction R of the tube bundle 2 of for example 20 mm to 35 mm, preferably 28 mm.

(16) When a force acts on the elastic element 5for example on account of contraction of the jacket 3there takes place a reversible, elastic deformation of the elastic element 5, in which the legs 52, 53 move away from one another, so that the free end regions 52a, 53a slide along on the inner side 3a of the jacket 3 in opposite directions. When there is a reversal of the temperature-induced contraction of the jacket 3, the elastic element 5 moves back again in the direction of its original state. Consequently, a decoupling of the thermal movements of the jacket and the tubes 20 takes place.

(17) TABLE-US-00001 List of reference signs 1 Heat exchanger 2 Tube bundle 3 Jacket 4 Intermediate space 5, 5.sup. Elastic element 6, 61 Spacing elements 10 Shell 20 Tubes 21 Core tube 50a First region 50b Protruding second region 51 Base 52 Leg 53 Leg 52a End region 53a End region 101 Inlet stub 102 Outlet stub 103 Inlet stub 104 Tube sheet 105 Outlet stub 200, 201 Tube layers 200, 200 Neighboring tube portions D Distance between jacket and outermost tube layer H Height R Radial direction L Longitudinal axis M Shell space W Angle