FR2655138A1 - Method for manufacturing a heat exchanger - Google Patents

Abstract

Method for manufacturing a heat exchanger with tubes provided with thin plates, in which a fluid to be heated flows, the ends of which tubes are connected together by means of deflection chambers composed of a trough and a lid joined by their edges, the edges being applied against each other with a view to assembling them by melting of metal.

Description

= 1

  The present invention relates to a method for manufacturing

  cation of a heat exchanger with tubes fitted with lamellae, o circulates a fluid to be heated and the ends of which are connected together by means of deflection chambers composed of a tank and a cover assembled by their edges , the edges being pressed against each other

  the others for their assembly by metal fusion.

  Such heat exchangers are known from US Pat. No. 3,982,587 for automobile radiators. The various

  radiator tubes pierce a tank that protrudes outside-

  all the tubes This tank is covered with a cover

  key welded on it In this case, the parallelism in plan

  of the tank and the lid is decisive for obtaining a weld

  waterproof, parallelism which, however, is not always

  ensured as a result of stamping of these components.

  From patent DE-OS 2 358 318, a process is known for the manufacture of a tube radiator, the ends of which on a

  side are surrounded by a sheet metal element folded several times.

  The end of the tube is not put in a special shape, but

keeps its primitive form.

  Heat exchangers according to the preambles to the

  equivalent vendications are known and consist of

  copper or special steel tubes fitted with copper strips

  glass or special steel The part carrying the slats is heated by a gas burner, the tubes being traversed

  by water to be heated by the heat exchanger The diff

  -2- different tubes can be hydraulically in series and / or in parallel, their ends being interconnected by deflection chambers which connect at least two

  of these tubes The deflection chambers are made of special steel

  cial and each include a tray and a profi-

  strips which together form the deflection chambers The tank and the lid each have an edge, both

  edges being applied one on the other and welded together.

  Welding is done with argon, the electrode being moved

  parallel to the contact face of the edges.

  This method has drawbacks because the pa-

  parallelism in plan between the container and the cover is a

  a decisive condition which, however, is not always met

  bends as a result of stamping of these components Asperities inside the weld to be produced, therefore of the contact face between the two components at the edges, which are manifested by a more or less significant gap between the edges to be joined by welding, create holes in the weld, or it happens that in places, there is no welding at all for several millimeters

length.

  Another difficulty concerns the correct fixing of the tank

  and of the cover applied one on the other in the dispo-

  clamping fixture for welding If the edges of the two

  components do not overlap exactly, there is a

need equality.

  The object of the invention is to produce a welding which avoids

  the above mentioned disadvantages.

  This object is achieved, in accordance with the invention, by the fact that

  the edges in contact with each other are folded together

ble or separately.

  -3- This folding means that either the container fits into the cover or the cover into the container, along their edges so that the position of one component with respect to the other is exactly defined. any gap between the two components has no effect, the components being in direct contact with each other at least along the

  folded part of the edge By choosing appropriate dimensions

  properties, we can get a tight junction between the

  components, the edge of the inner component is normal-

  the cover, protruding from O to 2 mm that of the component

  external health, normally from the tank This results in a po-

  inclined position of the electrode at an angle between 0 and 900 As an alternative, the two components can be

  assembled by welding or soldering.

  In one embodiment of the invention, it is proposed to

seem the components by welding.

  When brazing instead of welding, a filler metal

  in the form of a sheet is placed between the two compo-

  health. The assembly thus preformed can then undergo brazing in

  a continuous oven, preferably under an inert atmosphere.

  The heat exchanger produced according to the compliant process

  mement the invention not only has the advantage of easier and cheaper manufacturing than in the state

  current technology, but also an absolute tightness

  read. Using the figures in the drawing, two are described below.

  exemplary embodiments of the invention, the same references

  these indicating the same details in different fi-

  gures. -4- These figures show: Fig 1, a complete view of a heat exchanger,

  Fig 2, an embodiment of a heat exchanger

their welded, and

  Fig 3, an exemplary embodiment of a heat exchanger

soldered together.

  The heat exchanger in fig 1 is the heat exchanger

  their primary of an instantaneous or circulating water heater,

  running on gas, heated by a gas burner not shown

  felt The heat exchanger is made up of 1 cooking tubes

  glass or special steel, arranged parallel to each other

  tre, at a distance 2 The tubes are fitted with lamellas 3 made of copper or special steel, the block of lamellas 3 being each time limited by a border 4 which is also used for fixing the heat exchanger The tubes pierce the borders 4 and are interconnected by deflection chambers 6 which can communicate only

  two or more tubes The deflection chambers consist of

  install a container 7 looking at the tubes, and a cover 8 facing the other side The container and the cover are

  two elements that must be assembled along a base

  hard or of a soldering joint 9, waterproof, by a metal melting process The tank and the cover

  are made of copper or special steel and formed by stamping

  ge to create an interior, namely the deflection chamber

  The first and last deflection chambers 9,

  namely 10 and 11, are provided with a water connection 12 res-

pectively 13.

  Fig 2 shows the welding process for the assembly

  blocking of the container with the cover, in a mounting This

  floor includes a seat 14 and a punch 15 between them

  which is tight the edge 16 of the cover 8 and of the tank 7 This

  edge is provided with a fold 17 forming an angle of 900 screws

  opposite the edge This rim can be oriented towards the tank or

  the cover The cover placed inside is

  d from the edge of the tank, which it can exceed by 2.0 mm at most

  mum It would also be possible to fit the tray into the cover. A welding electrode 18 is then

  moved, at an angle of 0 to 900, along the rim com-

  Mun to join the two components by welding The less one component exceeds the other, the more the electrode is

upright.

  It is also possible to fold the edge of the tank and the cover

  separate the two components in assembly 14/15 before assembling them for welding In each case, care must be taken to bend the edges, in common or separately, only after having assembled them correctly to ensure impeccable contact in view of

  welding Even if welding does not take effect in the

  tie plane of the edges it will do so at least at the end of the

part folded.

  In the embodiment according to fig 3, the edges

  tray 7 and cover 8 are folded separately and

  seem by brazing, after interposing a sheet

  le 19 The folding of the edges is done in the same way as

  for fig 2 It is only necessary to ensure the positioning

  this correct from the sheet 19 which forms a strip All that goes beyond the edges is melted during brazing The three components, namely tray 7, cover 8 and sheet

  19 interposed, give rise to a tight assembly of

  that these components can no longer be disassembled easily

  before brazing The assembly can be done by soldering or simple brazing The tank and the cover

  can both be stamped, but it is also pos-

  likely to execute one as a plan element.

-6-

Claims (2)

Claims   1 Process for manufacturing a heat exchanger   with tubes fitted with strips where a fluid circulates   to be heated and the ends of which are interconnected   through composite deflection chambers   of a container and a cover assembled by their edges, the edges being applied against each other for their assembly by metal fusion, characterized in that after assembly, the edges (16) are folded together.   2 Process for manufacturing a heat exchanger   with tubes fitted with strips where a fluid circulates   to be heated and the ends of which are interconnected   through composite deflection chambers   of a container and a cover assembled by their edges, the edges being applied against each other for their assembly by metal fusion, characterized in that after assembly, the edges (16) are folded separately.