FR2570812A1 - HEAT EXCHANGER WITH A BEAM OF TUBES LODGED IN A BODY - Google Patents

Abstract

HEAT EXCHANGER WITH A BEAM HOUSED IN A BODY AND WHOSE TUBES ARE FIXED IN TUBULAR END PLATES, THE BODY CONSISTING OF A METAL ENCLOSURE TUBE AND TWO METALLIC END TRUNKS, AND THE TUBULAR PLATES, IN THE LIMITS OF THERMAL EXPANSION AND WITH INTERPOSITION OF SEALING MEANS, IN THE END TRUNKS WHICH ARE CLOSED ON THE ENVELOPE TUBE ARRANGED BETWEEN THEM AND RUN BY A SECONDARY FLUID. THE ENDS WITH REGARD TO THE END TRUNKS 4, 4 AND THE ENVELOPE TUBE 3 ARE EQUIPPED WITH RIMS 10, 11 FLAPED DOWN AND DIRECTED TO THE EXTERIOR. THE ANGLE FORMED WITH THE LONGITUDINAL AXIS OF THE ENVELOPE TUBE IS 45 MIN. AND 90 MAX. A SEAL 12 PROVIDED ON EACH TUBULAR PLATE 9 ENSURES ITS TIGHTNESS WITH RESPECT TO THE ENVELOPE TUBE 3 AND TO THE END TRUNK 4, 4; IT IS CLOSED BETWEEN TWO COLLAR RINGS IN LOOK. CLAMPS 13, 14 ARE PLACED ON THE FLAPED COLLARS. THE INVENTION ALLOWS ECONOMICAL PRODUCTION, SIMPLE ASSEMBLY AND GREAT COMPENSATION FOR TOLERANCES.

Description

The present invention relates to a heat exchanger comprising

  as a bundle housed in a body and the tubes of which are fixed in tubular end plates and traversed by a primary fluid, the body comprising a metal envelope tube and two metal end sections, and the tubular plates being

  mobile, within the limits of thermal expansion and with interposi-

  tion of the sealing means, in the end sections which are clamped on the casing tube disposed between them, traversed by a fluid

  secondary and having pipes for the secondary fluid.

  Patent application of the Federal Republic of Germany

  published under number 31 10 489 already describes a combined heat exchanger

  carrying a body in which is housed a bundle of tubes. Extremes

  mites from the tubes of the heat exchanger are held in tubular plates and traversed by a primary fluid. The body consists of a metal casing tube, two ferrules and two covers which are assembled by tie rods and nuts. The glass plates are held in the covers and the ferrules, with interposition of seals, so as to be movable within the limits of thermal expansion. The ferrules bear the

  tubing for a secondary fluid which, inside the receiving tube

  lop, sweeps the outside of the heat exchanger tubes.

  The constitution of such a heat exchanger is very expensive

  because many spare parts are necessary, imposing cost

  machining operations and a long assembly time. This is how the body comprises five spare parts which, including the commercial envelope tube, must undergo a rework machining without which

  proper application of the pieces on top of each other would be necessary

  sible, in particular on the assembly flanges of the envelope tube and the ferrules. Many seals are also necessary to seal the body parts together and relative

  to the tubular plates, and to separate the fluid circuits.

  U.S. Patent No. 3,426,841 describes a

  tube bundle heat exchanger, in which the plastic tubes

  ticks are held in a tubular plate also made of a plastic material. The body is also made up of

  plastic parts, a tubular central part being provided with

  end locks. The tubular central part and the covers have flange type collars at their ends, the flange of a tubular plate extending between two opposite collars. A

  gasket is placed between each collar and the tube plate

  laire. The body parts are fixed by clamping rings so as to apply the flanges to the tube plate. The thermal expansion of the tube bundle must be absorbed by the elasticity

tubular plates.

  This heat exchanger certainly presents a simple constitution as a result of the production of the body parts and of the fixing means, but also the drawback of being entirely constituted by plastic parts. The plastic materials are chosen so

  to be able to be melted together, which allows a fusion of the outer edge

  of the tube plate on the flange type collars. Independent

  especially as the fact that heat exchangers made of metallic materials are necessary for numerous applications and that no plastic material can then be used, another problem resides in the fact that the known mounting is only possible with tubular plates relatively elastic. The use of a bundle of tubes with rigid tubular plates, having limited mobility in the body, is therefore impossible. The known heat exchanger must finally be manufactured with tight tolerances, because the opposite faces of the flange type collars and the interposed collar of the tube plate are practically parallel, so that a

  compensation of tolerances by tightening the collars is impossible.

  The invention therefore aims to develop a heat exchanger of the type described in the introduction, so that it consists of simple parts, of economical production, that it allows a large

  compensation of tolerances and that its assembly is extremely simple.

  According to an essential characteristic of the invention, the end sections and the envelope tube are provided at their ends opposite collars directed towards the outside and folded down, the angle relative to the longitudinal axis of the envelope tube or end sections being 45 minimum and 90 maximum; each tube plate is provided with a seal, which seals it with respect to the envelope tube and the end section, and clamped simultaneously between two flanges folded down opposite; and clamps are placed on the folded flanges, the shape of said collars

  tightening corresponding to that of the flanges folded down opposite.

  The invention has the following main advantages:

  heat gor consists of an extremely small number of parts, which can be produced with relatively tolerances

  large and require no rework. The seal ensures the watertight

  between the tubular plate and the two parts of the body to be assembled

  bler and simultaneously compensates for manufacturing tolerances and

  variations in length. The realization of the clamping means per-

  puts a simple tightening, screwing the clamp producing a clear longitudinal translation of the body parts one on the other. The sealing device also allows translation

  significant by thermal expansion, without loss of tightness.

  In a preferred embodiment of the invention, the angles of two facing flanges are equal to each other and approximately with respect to the longitudinal axis of the body. This symmetrical shape of the section of the assembly device has the following advantage: the clamp also has a symmetrical section, so that the sides cannot be swapped during assembly. According to

  arrangement of the heat exchanger, it can however be

  geux that the end sections have a substantially square flange and that the flange of the facing body is arranged at an angle <60. The clamp must then have an appropriate shape, the flange having the smallest angle ensuring relative translation when tightening the collars. Such a device is particularly judicious when the bundle of tubes must be introduced with the envelope tube between the fixed end sections 4. and the tubular plates must penetrate only slightly into

the end sections.

  A particularly favorable embodiment of the invention resides in the combination with a leak indicator, constituted as follows: the face of the seal facing the tubular plate has a groove disposed along the circumference of the tubular plate and connected to the outer face of the heat exchanger by at least one radial channel of the seal. In the event of a leak between the tube plate and the envelope tube or between the tube plate and an end section, this judiciously integrated leak indicator

  at the seal directs the fluid which escapes on the external face

  of the heat exchanger and prevents passage through the other fluid. This avoids damage resulting from the mixture of different fluids. The fluid outlet indicates the presence of a leak. To

  that the leakage fluid outlet is not limited to the assembly points

  clamping collars, it is advantageous that the clamp

  Rabies has radial openings with a section at least equal to that of the radial channels of the seal. So that the passage of a possible leak is ensured even when the body parts are tightened by the collar and the resulting deformation of the seal,

  and according to another characteristic of the invention, the throat is cons-

  formed by a rigid fur and the radial channel by an independent tube

formable.

  In a preferred embodiment of the seal

  the section of the latter has the shape of a trapezium whose base face is applied to the tubular plate and whose side faces are applied to the folded-down flanges of the body parts. A large area of application of the seal on the corresponding faces is thus ensured, independently of the tightening of the collar. Such a device is recommended in particular when

  the angles of two facing flanges are equal.

  The seal may usefully have a round section when the angles of two facing flanges differ. Such a seal

  seal is easily adaptable to any shape.

  According to another characteristic of the invention, a clamp for each pair is provided with lugs or a stirrup for fixing the heat exchanger. Separate fixing means and their mounting on the body of the heat exchanger are therefore unnecessary. A particularly simple and economical production of the envelope tube is obtained when it is constituted by a tubular body.

  stretched area with tubing formed for the secondary fluid.

  The end sections of the body can in known manner be constituted by covers provided with pipes for the primary fluid, The invention however also makes it possible to constitute the end sections of the body by connection tubes of the same diameter as the tube envelope. A particular advantage of this measurement is obtained when these connection tubes are constituted by tubes from an already existing network of pipes, which avoids

  additional covers and tubing for the primary fluid.

  Other characteristics and advantages of the invention will be

  better understood using the detailed description below of example

  embodiments and the accompanying drawings in which: FIG. 1 represents (with partial section) a heat exchanger with a bundle of tubes and assembly by clamps;

  FIG. 2 shows on a larger scale an alternative embodiment

  tion of detail X; Figure 3 is an elevation along the axis III of Figure 1; Figure 4a shows an alternative embodiment of Figure 2; FIG. 4b represents a sealing element of round section at rest; and Figure 5 shows the mounting of a heat exchanger in a

existing piping network.

  FIG. 1 represents a heat exchanger 1 with a body 2 comprising a metal casing tube 3 and two end sections

  metallic, made in the form of covers 4 and 4 '. The tube

  loppe 3 has two pipes 5 and 6 for the inlet and outlet of the secondary fluid. As shown in the partial section on the left-hand side of FIG. 1, the envelope tube 3 contains a bundle of several tubes 7, the ends 8 of which are held in a

rigid tubular plate 9.

70812

  The envelope tube 3 has at its end a flange

  folded down 10, directed outwards, the angle a formed by the adhesive

  rette 10 and the longitudinal axis of the heat exchanger being approximately. The side of the cover 4 facing the envelope tube 3 also has a folded flange 11, directed towards the outside and which, like the flange 10 of the envelope tube 3, forms a

  angle a of about 60 with the longitudinal axis of the heat exchanger

  their 1. Between the two folded flanges 10 and 11 is a seal 12 of trapezoidal section. The inner envelope face of the seal 12, that is to say the base of the trapezoid, is applied to the outer circumference of the tubular plate 9 and its lateral faces are applied to the folded flanges 10 and 11, the

  seal thus simultaneously ensuring the seal between the tubular plate

  slide 9 on the one hand and the envelope tube 3 and the cover 4 on the other

go.

  An identical folded collar device 10 and 11 with a seal 12 is located at the other end of the envelope tube 3,

  namely the connection of the latter with the cover 4 '. Col-

  clamps 13 and 14, the cross section of which corresponds to that of the collars

  folded tabs 10 and 11, are provided for fixing covers 4 and 4 'on the envelope tube 3. The two clamps 13 and 14

  of a pair are placed practically on the whole circumference of the dis-

  positive constituted by the folded-down flanges 10, 11 and the seal 12 interposed, and are tightened by the bolts 15 and nuts 16 which act on the lugs 13 'and 14' of the collars 13 and 14. The more the nuts 16 are turned on the bolts 15, plus the clamps 13, 14 are lowered on the folded-down flanges 10, 11 and thus cause the inclined faces to move the cover 4 or 4 'relative to the casing tube 3. The pressing force acting on the seal 12 is thus increased simultaneously. As

  shown in Figure 1, the front faces of the covers 4 and 4 '

  try pipes 17 and 17 'for the primary fluid.

  Figure 2 shows on a larger scale an alternative embodiment of detail X of Figure 1. As on the latter, two folded flanges 10 and 11 are opposite, which each form the same angle a with the longitudinal axis of the heat exchanger. The

  seal 12 of trapezoidal section is located between the collars

  tabs 10 and 11. The face 18 of the seal 12 opposite the tubular plate 9 has a circumferential groove 19, connected by a radial channel 20 to the outer face of the seal 12. The latter therefore has on the face 18 two sealing sectors, which act as separate seals. When a leak appears in fact on one of the sealing sectors, the escaping fluid is directed outward through the groove 19 and the radial channel 20, and therefore cannot

  not reach the other fluid, which could cause dom-

  important mages under certain conditions.

  A rigid fur 21 is provided to maintain the shape of the

  groove 19, because such seals 12 are usually made

  made of a material with rubber elasticity. The radial channel 20 is constituted by a non-deformable tube 22. So that the only outlet for a possible leak is not on the ends of the collars 13, 14 formed by the lugs 13 ', 14', which is inconvenient depending on the position of the heat exchanger, the clamps 13 and 14 also have radial openings 23, so that the leak

  is very quickly detectable by the liquid outlet.

  FIG. 3 represents an elevation along the axis III-III of FIG. 1, the same parts bearing the same references as in FIG. 1. This elevation represents the cover 4 ′ with the flange 11 of larger radius and the tubing 17 ', through which a part of the tubular plate 9 is visible with the ends 8 fixed to the tubes. Hose clamps 13 and 14 each practically cover

  the half-circumference of the collar 11, so that a sufficient space

  health remains between the legs 13 'and 14' directed radially towards

  the outside for tightening using bolts 15 and nuts 16.

  A bracket 24 is welded to the lower clamp 14 and its projecting ends 25 have fixing holes, so

  that the bracket 24 is used for fixing the heat exchanger.

  FIG. 4a represents an alternative embodiment of the device.

  assembly, in which the end section of the exchanger

  heat must be constituted by a tube 27 of the network of pipelines-

  tions having the same diameter as the envelope tube 3. The connection tube 27 comprises a flange 28 substantially square, directed outwards and facing a flange 29 of the tube

  envelope 3, folded down and forming with the longitudinal axis of the sample

  heat gor an angle a of about 50. Between the folded-down flanges 28, 29 and the tube plate 9, in which the

  ends 8 of the tubes, there is a seal 30 applied

  as for the circumference of the tube plate 9 and on the adhesives

  folded rakes 28 and 29. The seal 30 initially has a round section, as shown in FIG. 4b; due to its elasticity and the forces it undergoes when tightening the folded flanges 28 and 29, it however deforms so as to ensure a large application surface both on the folded flanges and on the tubular plate 9. The seal sealing 30 includes, like the seal 12 previously described with the help of FIG. 2, a circular groove 19 with reinforcement fur 21 and a tube 22 constituting the radial channel 20. A clamp 31, suitable for angles

  flanges 28 and 29, is provided with branches 32 and 33 adapted

  - Tees at the angles of the flanges 28 and 29. The clamp 31 also has a radial opening 34 for the passage of the leakage liquid. With the assembly device shown in FIG. 4a, the tightening of the collar 31 produces a relative translation of the connection tube 27 and of the casing tube 33, by the sole action of the

  inclined faces of the collar 29 and of the branch 32.

  FIG. 5 schematically represents the assembly of the sample

  heat sink according to the invention in a network of existing pipes

  so much. The connection tubes 27 have the same diameter as the casing tube 3 of the heat exchanger 1. The latter is connected by clamps 13 and 14 to the connection tubes 27 in the manner previously described using the figure 1. As shown

  Figure 5 clearly, it is thus possible to save the covers.

  keys constituting the end sections, as shown

  shown in Figure 1, and the corresponding tubing for the fluid

  primary. Such mounting of the heat exchanger is possible uni-

  because the assembly device allows great compensation

  tolerances with a reliable seal between the two circuits

  cooked. Of course, various modifications can be made by those skilled in the art to the principle and to the devices which have just been described only by way of nonlimiting examples, without going beyond

of the scope of the invention.

2 5 7U 0 812

Claims (12)

Claims   1. - Heat exchanger comprising a bundle housed in a body and the tubes of which are fixed in tubular end plates and traversed by a primary fluid, the body comprising a metal envelope tube and two sections of metal ends, and the tubular plates being movable, within the limits of thermal expansion and with the interposition of sealing means, in the end sections which are clamped on the casing tube disposed between them, traversed by a secondary fluid and having tubings for the fluid secondary, said heat exchanger being characterized in that the end sections (4, 4 ′, 27) and the casing tube (3) are provided at their ends opposite facing flanges (10, 11, 28, 29) outwards and folded back, the angle (a) relative to the longitudinal axis of the envelope tube (3) or end sections   (4, 4 ', 27) being 45 minimum and 90 maximum; each place   that tubular (9) is provided with a seal (12, 30), which ensures its tightness   square with respect to the envelope tube (3) and to the end section (4, 4 ′, 27), and clamped simultaneously between two flanges folded down opposite (10, 11 or 28, 29); and clamps (13, 14, 31) are placed on the folded collars (10, 11 or 28, 29), the shape of said clamps (13, 14, 31) corresponding to that of   collars folded down opposite (10, 11, 28, 29).   2. Heat exchanger according to claim 1, characterized in that the angles (a) of two facing flanges (10, 11) are equal between them and about 60.   3. Heat exchanger according to claim 1, characterized in that the angles of two facing flanges (28, 29) are different,   a collar (28) having an angle of approximately 90 and the other collar lerette (29) an angle <60.   4. Heat exchanger according to any one of claims 1   to 3, characterized in that the face (18) of the seal (12, 30) opposite the tube plate (9) has a groove (19) arranged along the circumference of the tube plate and connected to the face outside of the heat exchanger (1) by at least one radial channel   (20) of the seal (12, 30). 708 12   5. Heat exchanger according to claim 4, characterized in that the clamp (13, 14, 31) has radial openings (23, 34) whose cross section is at least equal to that of the radial channels   (20) of the seal (12, 30).   6. Heat exchanger according to claim 4, characterized in that the groove (19) is formed by a rigid fur and the channel   radial (20) is constituted by a non-deformable tube (22).   7. Heat exchanger according to any one of claims 1   to 6, characterized in that the section of the seal (12) has the shape of a trapezium whose base face (18) is applied to the tube plate and whose lateral faces are applied   on the folded-down flanges (10, 11).   8. Heat exchanger according to any one of claims 1   6, characterized in that the seal (30) has a round section.   9. Heat exchanger according to any one of the claims   1 to 8, characterized in that a clamp (14) of each pair is provided with lugs or a bracket (24) for fixing the exchanger heat (1).   10. Heat exchanger according to any one of the claims   1 to 9, characterized in that the envelope tube (3) is constituted by a tubular body stretched with pipes (5, 6) -formed for the secondary fluid.   11. Heat exchanger according to any one of the claims   1 to 10, characterized in that the end sections of the body (2) consist of covers (4, 4 ') with pipes for the primary fluid.   12. Heat exchanger according to any one of the claims   1 to 10, characterized in that the end sections of the body (2) are formed by connecting tubes (27) of the same diameter.