TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to the field of the heat exchangers that are used to
exchange heat energy from one fluid to another without mixing them. The invention
relates more particularly to the large size exchangers of tube type comprising supports
making it possible to support a tube bundle intended to convey a fluid. The field
of the invention relates more specifically to that of the supports, such as rings,
comprising elements making it possible to secure tubes of the tube exchangers.
PRIOR ART
[0002] There are various types of exchangers used in industry which each address particular
needs depending on the desired heat transfer mode or the use of specific fluids. There
are plate, coil, block, fin and even tube exchangers. Other exchangers exist in the
prior art.
[0003] The tube exchangers are particularly appreciated for their resistance to high pressures,
the adaptation to different powers and to wide temperature deviations. They offer
the advantage of being economical and compact. They are used most often for heat transfers
between two volumes of water or more generally between a volume of liquid or of gas
and another volume of liquid or of gas.
[0004] Some tube exchangers comprise supports which make it possible to limit the head losses
of the fluids circulating in a calender and can also make it possible to better withstand
the mechanical stresses due to the vibrations of the structure, these vibrations being
mainly due to the arrival of the fluid in the calender which strikes the bundle, generally
at right angles.
[0005] Their design relies on an assembly of rods fastened to rings making it possible to
secure exchange tubes in which a fluid circulates. Generally, the ring is produced
from a template.
[0006] An exemplary exchanger is represented in figure 1, similar to that which is described
in the patent
US2009/0200004, in which circular baffle plates 8 also make it possible to secure the exchange tubes
9 along the exchanger by the presence of a plurality of holes allowing for the passage
of the tubes 9.
[0007] The plates 6, 7 are spaced apart in a calender 10 forming the shell of the exchanger
1 so as to secure, at the ends of the calender, the exchange tubes 9 all along the
exchanger 1. The tubes 9 are parallel and pass through the volume of the calender.
The baffle plates make it possible to circulate a fluid along a route 11 in the exchanger
1 from an inlet nozzle 4 to an outlet nozzle 5.
[0008] An inlet 2 makes it possible to circulate a first fluid in the exchange tubes 9.
The first fluid leaves through an outlet 3 at the other end of the exchanger 1.
[0009] An inlet 4 makes it possible to circulate a second fluid in the calender. The second
fluid leaves the exchanger through an outlet 5 at the other end of the exchanger 1.
[0010] The two fluids exchange heat by contact between the second fluid and the exchange
tubes.
[0011] One drawback with this structure is that it absorbs shocks and vibrations very little,
the gap between the tubes and the baffle plates used to secure them being very small.
Such a structure is likely to break under high stresses unless more of the holed plates
to support the tubes are provided, these plates here being the baffle plates providing
the support function. However, this solution would make the production of the overall
structure heavier by an increase in the number of parts, and would not make it possible
to observe the thermal dimensioning of the exchanger, the spacing between the baffle
plates being determined to be suited to the desired heat exchange.
[0012] Moreover, another drawback is that many head losses occur because of the course of
the fluid in the calender 10 imposed by the baffle plates 8.
[0013] Figure 2 represents another exemplary exchanger 20 of the prior art. The exchanger
type is tubular.
[0014] Rings 25 are spaced apart in a calender 21 forming the shell of the exchanger 20
so as to secure the tubes all along the exchanger 20.
[0015] Nozzles 22, 24 make it possible to inject or recover a fluid circulating in the calender.
[0016] A grid forms the interior of each ring making it possible to support a portion of
the effort used to secure the tubes and to minimize the lateral movements of the exchange
tubes. The term "interior" should be understood to mean the space delimited by the
dimensions of the ring, or its diameter and its thickness. The grid allows for an
easy passage of fluid in the calender because, on each ring, there is only one row
of tubes in every two which is secured with the rods. This leaves many sections of
passage for the fluid, which makes it possible to have low head losses. Figure 2 represents
a support plate 23 securing the tubes in a holed plate. The rings then positioned
allow for a recovery of effort to maintain a stable position for the tubes while making
it possible to absorb vibrations. In another possible configuration (tubular exchanger
with straight tubes) there are two support plates which secure the tubes in a holed
plate at the ends. The rings positioned between the two plates allow for a recovery
of effort to maintain a stable position for the tubes while making it possible to
absorb vibrations.
[0017] There are a number of possible manufacturing methods, but the most commonplace consists
in securing each rod of the ring in openings provided for this purpose using a template
specifically designed and manufactured to facilitate the assembly of a ring.
[0018] To ensure correct support of the tubes, rings very close together are required; at
least four rings, or three intervals, are required to secure a tube in all the directions
at right angles to its axis.
[0019] Figure 2 represents an embodiment of this design in which the rings are spaced apart
by 158.5 mm from one another. Consequently, the number of rings per apparatus is significant.
[0020] Moreover, devices according to the prior art generally incur a significant manufacturing
cost due to the fitting of numerous rings to secure the exchange tubes and lead to
head losses in the guiding of the fluid in the calender.
EXPLANATION OF THE INVENTION
[0021] The support of the invention makes it possible to overcome all or part of the abovementioned
drawbacks.
[0022] In particular, the support of the invention makes it possible to reduce the head
losses of the fluids as they are being guided in the calender, to reduce the weight
of an exchanger and to augment the securing of the exchange tubes.
[0023] To do this, there is proposed, according to a first aspect of the invention, a support
for an exchange tube bundle forming, in a cutting plane, a mesh, said support comprising
a ring, wherein the ring comprises fastening means making it possible to fasten, respectively,
on either side of the cutting plane of the ring, a first set of rods and a second
set of rods, said rods each having a form which constitutes a median plane, the median
planes of the first set being parallel to one another and the median planes of the
second set being parallel to one another, the orientation of the median planes of
the first set and of the median planes of the second set forming a first angle greater
than zero.
[0024] Such a device makes it possible to address all or part of the drawbacks of the prior
art, notably because it allows for an exchanger design having at least two times fewer
rings. This also makes it possible to reduce the head losses inside such an exchanger
provided with such supports.
[0025] According to a particular feature, the form of the rods is a "U" form, that is to
say a form having a central segment and two lateral segments forming the "U".
[0026] Advantageously, the first angle and the number of rods of each set are chosen so
as to form a frame exhibiting patterns corresponding to the mesh of the bundle.
[0027] Such a support makes it possible to improve the securing of the exchange tubes while
absorbing any vibrations. Such a support also makes it possible to increase the stability
of the exchanger and reduce the weight thereof.
[0028] Advantageously, the first angle is substantially equal to 90° or substantially equal
to 60°. These orientations make it possible to transversely immobilize, in an optimum
manner, the exchange tubes when they are arranged in the mesh formed by the set of
rods.
[0029] According to another particular feature, the section of the ring is square and/or
its lateral faces are substantially planar. This notably allows for easy adaptation
of the rods on either side of the ring.
[0030] According to an advantageous feature, the rods are fastened to the ring by shrink-fitting
into holes preformed on each of the lateral faces of the ring thus forming the fastening
means. Preferably, the shrink-fitting of the rods can be complemented by a step of
welding on each of the lateral faces of the ring.
[0031] Moreover, the rods can be welded without necessarily being shrink-fitted. In this
case, the weld forms the fastening means.
[0032] According to another technical aspect, the rods are:
- bent so as to obtain a U form, that is to say a form having a central segment and
two lateral segments forming the "U"; and/or
- formed by an assembly of several sections of rods so as to obtain rods having a U
form, that is to say a form having a central segment and two lateral segments forming
the U, and preferably three rod segments, one for the central segment and one for
each of the lateral segments.
[0033] In the latter case, the lateral segments are preferably machined, either by turning
before bending, or by grinding or milling before or after bending. It should be noted
that, in the general case, whatever the structure of the rod, the latter can be machined.
For example, a rod of single-piece structure formed by bending can be machined on
these lateral segments. This is particularly advantageous to reduce their thicknesses
(or their diameter) in order to adapt their flexibility if necessary, the machining
of the rods taking place before their bending.
[0034] Such features relating to the rods notably make it possible to be able to design
said rods in such a way that they exhibit a flexibility suited to best damping the
vibrations but above all to reduce the play of the tubes in relation to the mesh to
zero to have a firm contact.
[0035] Advantageously, the central section of the rods is more rigid than the lateral sections
of said rods. This makes it possible notably to guarantee that the flexibility seen
by the tubes at the center of the bundle is the same as the flexibility seen by the
tubes on the edges of the bundle.
[0036] Moreover, the invention also relates to a securing assembly comprising at least two
supports as described, the supports are spaced apart by a first distance and oriented
relative to one another by the first angle.
[0037] According to an advantageous feature the supports of the securing assembly are mounted
in series. This makes it possible notably to have an optimal rod mesh in order to
arrange the exchange tubes therein.
[0038] Moreover, the invention also relates to a heat exchanger comprising a calender which
encloses at least one bundle of exchange tubes and at least three exchange tube bundle
supports forming, in a cutting plane, a mesh, said support comprising a ring, wherein
the ring comprises fastening means making it possible to fasten, respectively, on
either side of the cutting plane of the ring, a first set of rods and a second set
of rods, said rods each forming a "U", each constituting a median plane, the median
planes of the first set being parallel to one another and the median planes of the
second set being parallel to one another, the orientation of the median planes of
the first set and of the median planes of the second set forming a first angle greater
than zero.
[0039] Such an exchanger makes it possible to address all or part of the drawbacks of the
prior art notably because it requires at least two times fewer rings than what is
proposed by the prior art. This also makes it possible to reduce the head losses inside
such an exchanger provided with such supports.
BRIEF DESCRIPTION OF THE FIGURES
[0040] Other features and advantages of the invention will be presented in a detailed description
illustrated by the following figures, with the help of the following description,
given in light of the appended drawings which represent:
- figure 1: a first tube exchanger of the prior art;
- figure 2: a second tubular exchanger with tubes of the prior art;
- figures 3A, 3B, 3C and 3D: rods having different "U" forms of the invention;
- figure 4: a 3D view of a ring according to the invention forming a support for fastening
the securing rods for the passage of exchange tubes;
- figures 5A and 5B: side and front views of a support according to an embodiment and
comprising a ring on to which are fastened securing rods for the passage of exchange
tubes.
DETAILED DESCRIPTION OF AN EMBODIMENT
Definitions
[0041] The term "ring" should be understood to mean an element having a closed contour having
a certain thickness and delimiting an interior space that is open on either side of
the closed contour. Generally, the closed contour has a substantially circular profile
but it may have a different profile, for example oval, oblong, etc.
[0042] The term "calender" should be understood to mean the shell of the exchanger into
which a fluid is injected for its cooling or its heating and which comprises rings
such as those defined in the present invention. Generally, a calender is cylindrical.
[0043] The expression "exchanger of calender tube type" should be understood to mean an
exchanger in which at least two fluids exchange heat, one fluid circulating in the
calender and a second fluid circulating in the tubes. The surface of the tubes serving
as support for the heat exchange between the two fluids.
[0044] The expression "rod in "U" form" should be understood to mean a rod assembled or
folded or bent which forms three branches, each branch having a join with another
branch forming an angle less than 180°. Figures 3A, 3B, 3C and 3D represent examples
of rods which can be used in the support of the invention.
[0045] The term "baffle plate" should be understood, notably for a good understanding of
the prior art, to mean a device making it possible to modify the direction of a fluid.
In the field of heat exchangers, the term "baffle" is often used. The prior art discloses
baffle plates that are used also to secure the tubes.
Description
[0046] A support for exchange tubes of the invention makes it possible to reduce the number
of rings of an exchanger while making it possible to offer enhanced flexibility in
the installation of an exchanger. Furthermore, the support of the invention makes
it possible to improve the securing of the exchange tubes while absorbing any vibrations.
The support of the invention makes it possible to increase the stability of the exchanger
and reduce the weight thereof.
[0047] Figure 4 represents a support 400 of the invention, suitable for a so-called "calender
tube" exchanger of circular form, comprising a ring 40 having a circular profile,
a first set 41 of rods 410 and a second set 42 of rods 420. The rods 410, 420 of the
two sets 41, 42 are fastened to the ring 40 on either side on the flanges of the ring
40 which respectively represent first and second lateral surfaces 401, 402 of the
ring 40 delimiting a thickness of the ring.
[0048] For the legibility of the figure, all the rods 410, 420 of each set are not represented.
[0049] According to the embodiments, the ring 40 can have a parallelepipedal section such
as a rectangle or a square or can even have a circular section.
[0050] Hereinafter in the description, a preferred embodiment is based on a ring 40 with
square section on which the first and second lateral surfaces 401, 402 of the ring
40 are substantially coplanar and spaced apart from one another by a distance equal
to the thickness of the ring 40.
[0051] For production convenience and to maximize the cylindrical surface of the exchanger
with respect to the number of tubes forming the bundle to be supported, each rod 410,
420 having a form which constitutes a median plane, the form of the rods here being
substantially a "U" form.
[0052] The "U" form can be obtained by bending, folding or by assembling three rod branches.
Moreover, the "U" form can be described as comprising a central segment provided with
two ends and two lateral segments provided with two ends, each of the lateral segments
being attached by one of their ends to an end of the lateral segment.
[0053] In the embodiment of figure 4, the first set 41 of rods 410 has a plurality of rods
410 parallel with one another, each rod 410 forming a "U" of which each end is fastened
to the first lateral face 401 of the ring 40, the ends of the rods in "U" form corresponding
to two ends of the lateral segments.
[0054] The second set 42 of rods 420 has the same properties as the first, except that the
rods 420 are fastened to the second lateral face 402 of the ring 30. Furthermore,
the median planes of the first set 41 are parallel with one another and the median
planes of the second set 42 are parallel with one another, the orientation of the
median planes of the first set 41 and of the median planes of the second set 42 forming
a first angle α greater than zero.
[0055] In this embodiment, the first and second sets 41, 42 of rods 410, 420 are oriented
relative to one another by a first angle equal to 90° in the example of figure 4.
[0056] In this figure, the axis (O, x) corresponds to the axis according to which the tubes
of the exchange tube bundle will be positioned so that they are colinear to said axis
(O, x).
[0057] Let (O, y, z) be a cutting plane normal to the axis (O, x) having for origin the
center of the ring so that the ring is substantially coaxial to the axis (O, x), the
coordinate system (O, x, y, z) also forming an orthogonal trihedron.
[0058] Let (O', y', z') be a first orthogonal coordinate system defining a first plane normal
to the axis (O, x) comprising substantially the central segments of each rod 410 of
the first set 41 of rods 410, said first plane being at a distance from the cutting
plane by a length equal to the length of the segment [O, O'], O' having the coordinates
(x1, 0, 0) in the coordinate system (O, x, y, z).
[0059] The median planes of the first set 41 are parallel with one another, parallel to
the plane (O', x, z') and orthogonal to the cutting plane (O, y, z).
[0060] Let (O", y" , z") be a second orthogonal coordinate system defining a second plane
normal to the axis (O, x) comprising substantially the central segments of each rod
420 of the second set 42 of rods 420, said first plane being at a distance from the
cutting plane by a length equal to the length of the segment [O", O], O" having the
coordinates (x2, 0, 0) in the coordinate system (O, x, y, z).
[0061] The median planes of the second set 42 are parallel with one another, parallel to
the plane (O", x, y") and orthogonal to the cutting plane (O, y, z).
[0062] The use of the qualifier "substantially" in the expression "a plane comprising substantially
the central segments of the rods" should be understood to mean that, the central segments
of the rods in "U" form not always being rectilinear, it is necessary to consider
an intermediate plane comprising substantially most of the central segments of the
rods.
[0063] Attention is drawn to the fact that the first and second planes are then at a distance
from one another by a distance [O', O"] equal to the sum of the thickness of the ring
40 and of the lengths of the lateral segments of the rods 410 of the first set 41
and of the rods 420 of the second set 42. Each of the first and second planes being
normal to the axis (O, x), the length of the rods 410 of the first set 41 are equal
to one another, as is the length of the rods 420 of the second set 42.
[0064] Such an orientation of the first and second sets relative to one another by a first
angle equal to 90° makes it possible to immobilize the exchange tubes in at least
one direction of each axis colinear to the axes (O, y) and (O, z) of the plane (O,
y, z) respectively in the first plane and in the second plane. In other words, the
orientation as illustrated makes it possible to immobilize the exchange tubes at least
on the axis (O', y') and the axis (O", z").
[0065] In fact, if we consider the first set 41 of rods 410 positioned for example vertically,
i.e. according to an axis colinear to the axis (O, z), each rod 410 has an abscissa
on the axis (O', y'). If we consider two successive rods of the first set 41, their
abscissae being denoted y'1 and y'2.
[0066] If we consider the second set 42 of rods 420, they are positioned horizontally since
they form an angle of 90° with the rods 420 of the first set 42, i.e. according to
an axis colinear to the axis (O, y). Each rod 420 has an ordinate on the axis (O",
z") . If we consider two successive rods of the second set 42, their ordinates are
denoted respectively z"1 and z"2.
[0067] By orthogonal projection of the first coordinate system (O', y', z') and of the second
coordinate system (O", y", z") in the cutting plane (O, y, z), the rods form a frame
in which the two successive rods of the first set 41 have abscissae denoted y1 and
y2 and in which the two successive rods of the second set 42 have ordinates denoted
respectively z1 and z2.
[0068] An exchange tube is modeled in this example by a substantially cylindrical structure
having an axis of revolution colinear to the axis (O, x). Such a tube passing between
two parallel rods of the first set 41 and two parallel rods of the second set 42 would
be contained between the abscissae y'1 and y'2 in the first coordinate system (O',
y', z') and would be contained between the ordinates z1 and z2 in the second coordinate
system (O", y", z").
[0069] Because of this, such a tube passes through the frame formed by the rods in the cutting
plane in a pattern of the frame that is here rectangular by virtue of the first angle
equal to 90°, the tube being contained between the abscissae y1 and y2 and between
the ordinates z1, z2.
[0070] The set of the tubes then forms an exchange tube bundle, said set forming, in the
cutting plane, a mesh.
[0071] In a manner not illustrated in this figure, when two supports 400 of the invention
share the same axis on (Ox), they are then, in this case, coaxial, and when they are
spaced apart by a first distance, then a tube can be secured on at least one axis
colinear to one of the axes (Oz) or (Oy) in any plane normal to the axis (Ox) .
[0072] Moreover, when three supports 400 of the invention share the same axis on (Ox), and
when the first and the second supports are spaced apart by a first distance and the
second and the third supports are spaced apart by a second distance, then a tube can
be secured on at least two axes colinear to the axes (Oz) and (Oy) in any plane normal
to the axis (Ox).
[0073] In one practical embodiment, the first and second distances can be chosen to be equal.
[0074] Thus, only three supports of the invention make it possible to form an assembly for
securing the tubes at least according to two axes colinear to the axes (Oz) and (Oy)
of the plane (O, y, z).
[0075] The invention therefore makes it possible to reduce the number of rings of an exchanger
making it possible to support a bundle of heat exchange tubes.
[0076] In practice, in order to have six contacts for each tube making it possible to secure
a tube in the exchanger, only three rings are needed. It should be noted that, in
the case where a tube might have only four contacts with the rods of the supports,
the tubes can still pivot. In such a configuration, it is sufficient to have two supports,
each of the tubes having two contacts per support. Consequently, in order to be able
to completely guide the tubes, it is necessary to have at least six points of contact
of the tubes with the rods of the supports, that is to say, at least three points
of contact in each plane.
[0077] Regarding the production of the rods, the latter can, for example, be welded on the
lateral faces of the ring or even shrink-fitted in holes of the same diameters on
the lateral faces of the ring.
[0078] In another embodiment, the rods can be fastened to the internal wall of the ring.
[0079] Figures 5A and 5B represent diagrammatic views of the ring 40, seen from the front
and from the side. Heat exchange tubes 50 are represented in figure 5B. They are supported
by rods 410, 420 of the first and second sets 41, 42 of rods 410 and 420 which form
a three-dimensional grid of the ring, illustrating, in this front view, a frame. The
frame thus represented by the grid, which can be seen in the front view, exhibits,
in this embodiment square patterns. The side view represents the set of horizontal
rods 42 on one side of the ring and the set of vertical rods 41 on the other side
of the ring. For the legibility of the figures, not all the rods are represented.
The lines 51 mark out each space which forms a frame into which an exchange tube can
be inserted and be secured in the exchanger, these spaces being delimited by the patterns
of said frame.
[0080] In another embodiment, the patterns of the frame can be triangular so that the first
set of rods forms, with the second set of rods, an angle of 60°. In this way, another
support that is coaxial and situated at a first distance and oriented relative to
the first support, for example, at an angle of 60° would make it possible to support
the exchange tubes on at least one axis colinear to one of the axes (Oz) or (Oy),
and do so in any plane normal to the axis (Ox).
[0081] In the same way, a third support positioned after the first two supports and having
undergone another rotation of 60° relative to the second would make it possible to
secure the heat exchange tubes on at least two axes colinear to the axes (Oz) and
(Oy), and do so in any plane normal to the axis (Ox).
[0082] Such a rod configuration can make it possible to define a frame exhibiting patterns,
one and the same pattern being able to be passed through by one or more tubes of the
exchange tube bundle.
[0083] In all the embodiments, the frames, and therefore the arrangement of the rods, are
designed to allow for a passage of a fluid in the calender while minimizing the head
losses and offer adequate securing for the exchange tubes.
[0084] In a preferred embodiment, the rods of one and the same set of rods are spaced apart
two by two by a distance substantially equal to two times a pitch defined by the exchange
tubes, the pitch being defined as the distance between axes of two contiguous exchange
tubes. In the case where the exchange tubes are cylindrical, these axes are the axes
of revolution of said cylindrical forms. In this way, the frame formed by the rods
is particularly suited to the mesh formed, in the cutting plane, by the exchange tube
bundle.
[0085] Advantageously, the pitch of the exchange tubes is substantially equal to 1.25 times
the diameter of the exchange tubes, this coefficient of 1.25 being able to be adjusted
according to the materials used. In practice, and advantageously, this coefficient
is substantially between 1.05 and 3, this depending on the materials used but also
on the operating pressure of the exchanger, on the manufacturing means, on the diameter
of the exchange tubes, and on the thermal dimensioning of the exchanger.
[0086] The form of the frame is therefore defined so as to allow the passage of a tube for
which the dimension of the section of the tube, its diameter when the tube has a circular
section, is smaller than the greatest distance defined by a pattern of the frame.
The difference between this diameter and this greatest distance defines a gap. Said
gap is calculated so as to optimize the head losses of the fluids and to ensure an
optimal securing of the tubes in the calender by virtue of the support through the
configuration of the supports, in particular the form of the patterns of the frame
formed by the rods.
[0087] The invention therefore makes it possible to reduce the number of rings needed in
an exchanger. This consequently makes it possible to:
- reduce the weight of the apparatus
- reduce the number of welds, notably welds of the rings on the insertion rails,
- reduce the manufacturing time, notably to obtain a saving on machining. The manufacture
is thus simplified.
[0088] Generally, a significant concern regarding the tube exchangers that comprise supports
for a tube bundle is to ensure a firm contact between the exchange tubes and the securing
rods in order to minimize the gap between the rod and the tube while ensuring a flexibility
so as to absorb any vibrations of the structure.
[0089] This flexibility, although it is not necessary to the securing of the rods, becomes
essential when there is a desire to reduce the gap to zero to have a firm contact.
In practice, the firm contact is possible only if one of the two parts in contact,
the tube or the rod, is adapted to the other, respectively the rod or the tube, hence
the need for flexibility. In other words since the theoretical gap equal to zero does
not exist, it is necessary to provide a deformation of the parts when they come into
contact with one another.
[0090] The flexibility provided in the rods is obtained by virtue of the length of each
side of the "U" form of each rod corresponding to the smallest length which links
the ring to the rest of the rod. This arrangement of the two sets and this organization
of the rods between them make it possible to obtain a flexibility of the installation
while ensuring the securing of the tubes by better contacts between the tubes and
the rods.
[0091] Moreover, in a preferred embodiment, the lateral segments of the "U" forms can be
machined, either by turning before bending, or by grinding or milling before or after
bending. This makes it possible to obtain the exact flexibility desired to secure
a row of tubes.
[0092] Furthermore, the "U" form can be formed with a number of rods assembled together,
preferably three, one for a central segment and one for each of the lateral segments.
This can make it possible to have a different flexibility on the edges of the "U"
forms, for example with rods of smaller diameter for example. Nevertheless, it would
be preferable to keep the central segment as rigid as possible, particularly when
the lateral segments exhibit a flexibility. In practice, given that a flexibility
is added to the lateral segments of the rods in "U" form, it is strongly recommended
that these central segments should remain rigid in order to guarantee that the flexibility
seen by the tubes at the center of the bundle is the same as the flexibility seen
by the tubes on the edges of the bundle.
[0093] The rods ensure, by deformation, a firm contact of the tubes and allows a greater
manufacturing tolerance for the positioning of the rods and the tubes.
[0094] It is also simpler to produce branch points between two rings in the calender. The
branch points are nozzles that make it possible to inject or recover a fluid in the
exchanger between the inlet and the outlet thereof.
[0095] Furthermore, the rods can be shrink-fitted and/or welded on to the rings via holes
drilled therein, notably on the lateral surfaces of said ring. In this case, there
is no longer a need for a template to position the rods. This solution makes it possible
to obtain a gain and a saving on a template. In practice, the drilling of the holes
is all that is needed to position the rods.
[0096] The exchange tube supports of the invention make it possible to reduce the weight
of the structure of an exchanger and to add a mechanical strength that better withstands
the shocks and vibrations of the structure.
[0097] The rods can notably be made of stainless steel, of steel, of carbon or more generally
of metal.
[0098] Finally, the solution of the invention promotes a heat exchange by reducing the head
losses of the fluids exchanging heat. In the case of such a tube bundle support, the
head gain is situated notably at the level of the head loss on the ring.
1. A support (400) for an exchange tube bundle forming, in a cutting plane, a mesh, said
support (400) comprising a ring (40), wherein the ring (40) comprises fastening means
making it possible to fasten, respectively, on either side of the cutting plane of
the ring, a first set (41) of rods (410) and a second set (42) of rods (420), said
rods (410, 420) each having a form which constitutes a median plane, the median planes
of the first set (41) being parallel to one another and the median planes of the second
set (42) being parallel to one another, the orientation of the median planes of the
first set (41) and of the median planes of the second set (42) forming a first angle
(α) greater than zero.
2. The support (400) as claimed in claim 1, wherein the form of the rods is a "U" form,
that is to say a form having a central segment and two lateral segments forming the
"U".
3. The support (400) as claimed in any one of claims 1 or 2, wherein the first angle
(α) and the number of rods (410, 420) of each set (41, 42) are chosen so as to form
a frame exhibiting patterns corresponding to the mesh of the bundle.
4. The support (400) as claimed in any one of claims 1 to 3, wherein the first angle
(α) is substantially equal to 90°.
5. The support (400) as claimed in any one of claims 1 to 3, wherein the first angle
(α) is substantially equal to 60°.
6. The support (400) as claimed in any one of claims 1 to 5, wherein the section of the
ring (40) is square and/or wherein its lateral faces (401, 402) are substantially
planar.
7. The support (400) as claimed in any one of claims 1 to 6, wherein the rods are fastened
to the ring by shrink-fitting into holes preformed on each of the lateral faces of
the ring.
8. The support (400) as claimed in any one of claims 1 to 6, wherein the rods are fastened
to the ring by welding on each of the lateral faces of the ring.
9. The support (400) as claimed in any one of claims 2 to 8, wherein the rods are bent
so as to obtain the "U" form.
10. The support (400) as claimed in claim 9, wherein the lateral segments are machined,
either by turning before bending, or by grinding or milling before or after bending.
11. The support (400) as claimed in any one of claims 2 to 10, wherein the rods are formed
by an assembly of several sections of rods so as to obtain rods having the "U" form,
and preferably three rod sections, one for the central segment and one for each of
the lateral segments.
12. The support (400) as claimed in any one of claims 2 to 11, wherein the central section
of the rods is more rigid than the lateral sections of said rods.
13. A securing assembly comprising two supports (400) as claimed in any one of claims
1 to 12, wherein the two supports (400) are spaced apart by a first distance and oriented
relative to one another by the first angle (α).
14. A securing assembly comprising at least three supports (400) as claimed in any one
of claims 1 to 12, wherein the supports are mounted in series, two successive supports
being spaced apart by a first distance and oriented relative to one another by the
first angle (α).
15. A heat exchanger comprising a calender which encloses at least one bundle of exchange
tubes and at least three exchange tube bundle supports forming, in a cutting plane,
a mesh, said support (400) comprising a ring (40), wherein the ring (40) comprises
fastening means making it possible to fasten, respectively, on either side of the
cutting plane of the ring, a first set (41) of rods (410) and a second set (42) of
rods (420), said rods (410, 420) each having a form constituting a median plane, the
median planes of the first set (41) being parallel to one another and the median planes
of the second set (42) being parallel to one another, the orientation of the median
planes of the first set (41) and of the median planes of the second set (42) forming
a first angle (α) greater than zero.