FR2497567A1 - HEAT EXCHANGER WITH PARALLEL TUBE BEAM AND METHOD OF MANUFACTURING THE SAME - Google Patents

Abstract

THIS PARALLEL TUBE BEAM HEAT EXCHANGER IS DESIGNED TO BE ABLE TO RESIST AGGRESSIVE ACTION OF FLUIDS BETWEEN WHICH HEAT EXCHANGES ARE DESIRED. ITS PLATES ARE OF STAINLESS STEEL AND ITS TUBES OF A PLASTIC MATERIAL, SUCH AS CROSS-LINKED POLYETHYLENE, LIKELY TO RESIST THIS AGGRESSIVE ACTION OF FLUIDS, BUT CANNOT BE SEALED OR BONDED TO STAINLESS STEEL. THE TUBES 15 ARE SET AT THE EDGES OF THE HOLES 16 OF THE PLATES; TO THIS EFFECT THE ENDS OF THE TUBES 17 IN PLASTIC MATERIAL HAVE A THIN STAINLESS STEEL INSERT WHICH IS CRIMPED WITH IT.

Description

Parallel tube bundle heat exchangers comprise

  generally two parallel plates, perforated with appropriately distributed holes, and a bundle of parallel tubes communicating each hole of one of the plates with a hole of the other plate, one of the two fluids participating in the heat exchange passing from the outer face of one of the plates on the outer face of the other plate passing through these tubes, while the other fluid involved in the heat exchange passes between these plates and outside the parallel tubes,

transversely to these.

  If it is desired to use such a heat exchanger to recover the calories from the fumes. dehydration of organic materials, such as alfalfa, for example, the exchange surfaces must be considerable, and, if the plates and tube bundles are of stainless steel of such quality that they can withstand the aggressive action fumes, the

  weight and cost of manufacture are prohibitive, and recovery

  calorie ration is not profitable.

  It would have been possible to consider replacing such a heat exchanger with stainless steel tubes by plastic tubes capable of withstanding the aggressive action of the fumes, of cross-linked polyethylene, for example, which would have made it possible to considerably reduce the weight and the price of such exchangers

  of heat, and could therefore have made such an operation

  calorie recovery, but unfortunately, it has not been possible so far to manufacture such heat exchangers

  of heat, the cross-linked polyethylene tubes being neither

  can not be bonded to stainless steel plates.

  The subject of the present invention is, as a new industrial product, a heat exchanger of the aforementioned type, in which the tubes are made of a plastics material capable of

  resist the aggressive action of the fluids between which

  heat exchange, such as polyethylene

  for example, which is neither sealable nor bondable to a

  stainless steel, as well as to the process that the

  Applicant for fixing such tubes to these plates.

  For this purpose, according to the present invention, is introduced into the end of the tube intended to be attached to a plate

  perforated, around the corresponding hole, a tubular insert

  re in a material resistant to aggression of the fluid that the

  cross-member, made of stainless steel, for example,

  mites the plastic tube and its insert into the corresponding hole of the plate, and the whole is crimped to the plate,

  after possibly shaping the edges of the corresponding hole

  to facilitate crimping; this crimping can be obtained by extension, by means of a simple dudgeonage operation, or,

  possibly by any other mechanical means allowing the ob-

  hold faster, and simultaneously on a more number or

  smaller tubes, so as to increase the speed of

and reduce the cost.

  The accompanying drawing shows by way of example an embodiment of the present invention: FIG. 1 is a sectional view and

  Figure 2 is a side view of such an exchanger.

  Figures 3 and 4 show the attachment of the end

  from a tube to a medium thickness plate.

  Figures 5 and 6 are similar views in the case of a thin plate; and Figures 7 and 8 are similar views in the case

a thick plate.

  The heat exchanger shown consists of four similar modules 1, 2, 3, 4, each having an upper plate 5 and a lower plate 6 pierced with holes joined in pairs

  parallel tubes of which only a few are

  felt above in 7, on an enlarged scale; one of the fluids whose heat is to be exchanged enters the upper part of the exchanger 8, through the inlet orifice 9, above the upper plate 5 of the first two elements 1 and 2 through which it passes through the tubes 7 to enter the lower chamber 10 of the exchanger, which can emerge through the holes of the lower plates 6 of the last two elements 3 and 4, to escape through the holes of their upper plate 5 and possibly be there collected in a chimney not shown; the condensation juices can slide on the sloped lower side He of the chamber 10 and escape through the hole

evacuation 12.

  The second fluid whose heat must be exchanged with that of the first arrives laterally through the end opening 13

  the exchanger 8 passes transversely between the parallel tubes

  the 7 of the four elements 1 to 4 of the exchanger, to escape laterally through the outlet orifice 14 at the end

opposite of the exchanger 8.

  When the stainless steel plates of the exchanger are of medium thickness, as shown in FIGS. 3 and 4, the ends of the plastic tube 17, such as crosslinked polyethylene, are introduced through its holes 16.

  and its insert 18, constituted by a small section of tube equal to

  very thin stainless steel; the crimping is then carried out in any appropriate manner, as shown

  in Figure 4 in 19; fixing is ensured.

  If the stainless steel plate is thinner, as

  shown in FIGS. 5 and 6, the crimping is facilitated and

  improve the seal by rounding the edges 21 of its hole 22 through which is introduced as previously the end of the tube 17 and its insert 18; crimping is then carried out at 23,

like before.

  In the case of a thicker stainless steel plate,

  like the one 24 shown in FIGS. 7 and 8, the shape is preformed

  lable the edge of its hole 25 so as to create a groove 26, pre-

  preferably at sharp angles, in which can be crimped at 27, as shown in Figure 8, the end of the tube 17 and its

  insert18 introduced into this shaped hole 25.

  It is understood that the different modes of

  of the invention which have been described above with reference to the

  annexed drawing have been given for information only and

  However, many modifications can be made without departing from the scope of the present invention.

  In particular, the number of modules

  The size of the heat exchanger varies according to the desired exchange surface, a single module being sometimes sufficient; any suitable device such as fumes saturator, permanent cleaning device, temperature flow control and

  pressures can be provided in 9, at the entrance of the exchanger;

etc.

2497567 1 - 1

Claims (7)

  1. Parallel heat exchanger with tube bundle;   likely to be crossed by fluids between   It is aggressive, with stainless steel plates pierced by holes joined in pairs by parallel tubes. in that these parallel tubes (7) are made of a plastic material able to withstand the aggressive action of the fluids entrained by the heat exchanger, such as the cross-linked polyethylene, for example, which it is neither sealable nor bondable to a stainless steel plate, and in that the ends of these tubes are crimped to the edges of the plate holes: the heat exchanger.   2. The heat exchanger according to claim 1, wherein the ends of the plastic tubes (17) have an insert (18) of stainless steel which is fitted with them at the edge of the holes. of the plastic plate (Figure 4).:! 3. Heat exchanger according to claim 2, caz:   characterized in that the stainless steel plates are small.   and the edges of their holes are rounded towards lti.   laughing and that the ends of the tubes and their inserts soxt crimped on these roundings (Figure 6).   4. Heat exchanger according to claim 1 [! characterized in that the stainless steel plates are m pa :: t - '   and its holes are shaped to create a groove (26), preferably   preferably at sharp angles, in which the end of the tube (17) and its   irnsert (a) introduced into this stuffed hole (25) (Figure 8).   5. Suitable for fixing a tube of plastic material, such as reticulated polyethylene, around a hole of a stainless steel plate to which it is neither sealable nor bondable for the realization of a heat exchanger according to one   1 to 4, characterized in that it introduces   the end of the tube (17) intended to be fastened to the tubular upright plate (18) in a mold resistant to the agrezrior of the fluid which traves through it, In stainless steel, for example, the extrusions of the tube and the insert are engaged in the hole in the plate, and the whole is crimped onto the plate.   6. The following process. - curacrr- n -   whereas, in the case of a plate made of thin-walled acer (20), the edge of its hole (3) is rounded, and it is crimped. end of the tube (17) and its nse: t 'E) acur of this round.   7. A method according to claim 5 characterized in that, being a relatively thick stainless steel plate (24) is created in the edge of its hole (25) a groove (26) and crimped the end of the tube (17) and its insert (18) in this groove (26).