JP7828369B2 - Heat Exchanger Port Insert - Google Patents

Description

The present invention relates to a port insert for a heat exchanger.

A plate heat exchanger (PHE) typically has two end plates between which a number of heat transfer plates are arranged in an aligned, i.e., stacked or packed, configuration.

In one known type of PHE, the so-called gasketed PHE, a gasket is placed between the heat transfer plates in a gasket groove pressed into the heat transfer plates. The end plates and heat transfer plates are pressed together by some type of clamping means, whereby the gasket seals between the heat transfer plates. Parallel flow paths defined by the gasket are formed between the heat transfer plates, with one channel between each pair of adjacent heat transfer plates. Two fluids, initially at different temperatures, supplied to and from the PHE through portholes in the end plates alternate through every other channel to transfer heat from one fluid to the other. The fluids enter and exit the channels through inlet/outlet portholes in the heat transfer plates, which form the inlet/outlet ports of the PHE, communicating with the portholes in the end plates.

Thus, at least some of the portholes in the end plates of the PHE are supply portholes used for supplying fluid to and from the PHE, while the remaining portholes are blind portholes that are not used for supplying fluid. A set of connection means, such as studbolts, is provided for each of the portholes in the end plates. Typically, the studbolts are evenly spaced around the porthole and protrude from the outside of the end plate, allowing external fluid connections for the supply portholes and blind covers for the blind portholes to be connected.

A filter can be placed in the inlet port of a PHE to prevent fibers and solids contained in the fluid from entering the channels and fouling the PHE. Known filter configurations for PHE ports include two port inserts. The first port insert includes a tubular filter and an annular flange extending radially from the outside of the tubular filter. The second port insert includes a short tube and an annular flange extending radially from the outside of the tube. The first port insert is inserted into one porthole in an end plate from one side of the PHE and into the corresponding port, with the tubular filter positioned within the port and the flange abutting a gasket, which in turn abuts the outside of the end plate. The second port insert is inserted into the corresponding porthole in the other end plate from the opposite side of the PHE and into the port, with the tube positioned inside the port and the flange adjacent to the gasket, which in turn abuts the outside of the end plate. When positioned in this manner, the tube of the second port insert protrudes into the filter of the first port insert, with the filter surrounding the tube along its short edge. Centering the filter within the port typically requires that the flanges of the first and second port inserts be concentric with their respective port holes in the end plate. Therefore, the flanges are sized after the stud bolts are placed around the periphery of the end plate port holes so that they engage the outer edges of the flanges and properly position the flanges relative to the port holes.

Typically, each PHE model has several different connection standards, each with a specific location, size, and number of stud bolts. This means that many different filter arrangements with different flange diameters must be offered, typically one filter arrangement per connection standard.

Furthermore, removal of the filter, and thus the first and second port inserts, may be necessary, for example in connection with maintenance of the PHE. To facilitate this removal, the first and second port inserts of known filter configurations include handles in the form of bars welded to the inner edges of the flanges of the first and second port inserts and extending diametrically therein. In some cases, pulling on these bars can loosen them, making filter removal difficult.

Considering the above, there is room for improvement in the area of PHE filter configuration.

The object of the present invention is to provide a port insert for a heat exchanger that reduces the number of different filter configurations that must be offered for a particular PHE model and eliminates the need for a handle to easily remove the port insert. The basic concept of the present invention is to provide a port insert with a design that accommodates different connection standards and allows for easy, non-destructive withdrawal of the port insert. The port insert is defined in the accompanying claims and described below.

A heat exchanger port insert (hereinafter simply referred to as a "port insert") according to the present invention comprises a tubular portion and a flange protruding from the outside of the tubular portion. The heat exchanger port insert is characterized in that the flange comprises an annular inner portion and a first fastening projection. The first fastening projection has an outer contour. The inner portion comprises an annular inner edge along which the inner portion is joined to the tubular portion. The first fastening projection protrudes from the annular outer edge of the inner portion so as to locally increase the width of the flange at the first fastening projection.

The first fastener, as the name suggests, fastens the port insert to the heat exchanger. The fastener may be non-permanent, i.e., removable.

The tubular portion may include or be a filter or a solid tube.

The tubular portion may have any suitable cross-section, constant or varying, such as a circular, oval, or smooth triangular cross-section, typically depending on the design of the port of the heat exchanger in which the port insert is to be used. Similarly, the flange may have any suitable design. Typically, the design of the inner portion of the flange, particularly the inner edge of the inner portion, is adapted to the design of the tubular portion. Furthermore, the design of the inner portion of the flange is typically adapted to the design of the porthole in the end plate of the heat exchanger in which the port insert is to be used.

The inner portion of the flange may have an essentially constant width along its annular extension.

The width of the flange may be measured perpendicular to the annular extension of the inner portion of the flange.

The inner portion of the flange and the first fastening projection may be integrally formed. Alternatively, the first fastening projection may be secured to the inner portion by welding, screws, or other suitable method.

The first fastening projection is positioned to engage with a connecting means positioned around a port hole in one end plate of the heat exchanger in which the port insert is configured for use. This allows the flange of the port insert to be fixed or attached to the end plate, while the tubular portion is centered on the corresponding port in the heat exchanger. The first fastening projection can be designed in a myriad of ways to allow the same port insert to be used with heat exchangers that have different connecting means locations, numbers, types, etc. In that the first fastening projection protrudes from the inner portion of the flange, it can be easily grasped and pulled to remove the port insert from the heat exchanger, which may be, for example, a plate heat exchanger.

The tubular portion and flange of the port insert may be permanently joined or may be integrally formed.

The port insert may be for a filter device, i.e., may be contained within a filter device, and the filter device is fluid permeable so that fluid may pass through or leak to be filtered.

A port insert may be included in a filter configuration with another port insert, the two port inserts being arranged to engage with one another, and one of the port inserts having a tubular portion containing a fluid-permeable filter through which fluid may pass or leak to be filtered.

The port insert may be arranged to non-permanently, i.e., removably, engage with the heat exchanger to allow non-destructive engagement and disengagement between the port insert and the heat exchanger.

The heat exchanger may be a plate heat exchanger. The plate heat exchanger may include a pack of heat transfer plates with portholes forming ports extending through the pack of heat transfer plates. The tubular portion of the port insert may be configured to extend from one side of the pack of heat transfer plates into one of the ports. The plate heat exchanger further includes two end plates disposed on opposite sides of the pack of heat transfer plates, a first of the end plates configured adjacent to the one side of the pack of heat transfer plates and extending substantially parallel thereto, with a porthole aligned with one of the ports extending through the pack of heat transfer plates. The tubular portion of the port insert may be configured to extend through the porthole of the first end plate. Furthermore, the flange of the port insert may be configured to be non-permanently, i.e., removably, and directly or indirectly (i.e., via one or more intermediate components), fixed to the outside of the first end plate. The first fastening projection may be configured to engage with a connecting means in the form of a bolt or pin, with or without threads. The port insert can then be designed so that the first fastening projection provides a space for receiving the first bolt or pin. Such a design can enable reliable, non-permanent, i.e., removable, attachment of the port insert to a heat exchanger of conventional design.

As mentioned above, the first fastening projection can have many different configurations. According to one embodiment, the first fastening projection branches into first and second protruding portions extending away from the inner portion of the flange. Furthermore, the first bolt-receiving space includes a cavity formed by the first and second protruding portions. Thus, the cavity of the first bolt-receiving space extends between the first and second protruding portions. The first and second protruding portions can be spaced a distance ≥ 0 from the outer edge of the inner portion of the flange. The first and second protruding portions can reunite to form a closed cavity. This embodiment can enable a secure and strong confinement of a connecting means, such as a bolt, from multiple directions in a mechanically simple manner.

The cavity can be designed in many different ways. According to one embodiment of the present invention, the cavity has a finite number of axes of symmetry, which means that when the port insert is viewed from above, the cavity has a shape other than circular. The connecting means of plate heat exchangers typically have a circular cross-section. This embodiment of the present invention may therefore allow for tight engagement between the inner edge of the cavity defined by the first and second protruding portions and connecting means of different sizes and/or positions.

By way of example, the cavity may have up to two axes of symmetry, thereby allowing for clear engagement between the inner edge of the cavity and connecting means of different sizes and/or positions.

The port insert may be configured such that the longitudinal extension of the cavity, measured normal to the outer edge of the inner portion, is greater than the lateral extension of the cavity. The lateral extension of the cavity is perpendicular to the longitudinal extension of the cavity. This configuration may allow for tight engagement between the inner edge of the cavity and connecting means located at different distances from the center of the port hole in the end plate.

The lateral extension of the cavity may vary along the longitudinal extension of the cavity. This configuration may allow for tight engagement between the inner edge of the cavity and different sized connection means located at different distances from the center of the porthole in the end plate.

The port insert may be designed so that the shape of the cavity, and therefore the inner edge, is defined by the outer contour of an object formed by multiple, i.e., two or more, imaginary circles of different diameters. The imaginary circles are arranged along an imaginary straight line, with adjacent imaginary circles partially overlapping each other. The imaginary straight line may be parallel to the normal direction of the outer edge of the inner portion. This design may allow for a clear and tight engagement between the inner edge of the cavity and connecting means of different sizes and positions.

The first fastening projection may include a second bolt or pin receiving space including a first recess in a first outer edge portion of the first fastening projection. Such a design may enable reliable fixation of the port insert in heat exchangers of conventional designs.

The first outer edge portion described above may be configured anywhere along the outer edge of the first fastening projection, for example along the outer edge of the inner portion of the flange, at a distance from the outer edge. However, according to one embodiment of the present invention, the first outer edge portion extends from the outer edge of the inner portion of the flange in a direction away from the inner portion. This configuration may enable a mechanically simple design of the port insert.

According to one embodiment of the port insert of the present invention, the first contour portion of the outer contour of the first fastening projection defines the aforementioned first recess at the first outer edge portion of the first fastening projection and has the essential shape of an arc of a circle with radius r1. As mentioned above, the connecting means of a plate heat exchanger typically has a circular cross section. This embodiment therefore allows for a clear and tight engagement between the first recess and the connecting means, thereby enabling strong and reliable attachment of the port insert to the end plate of the heat exchanger.

The port insert may be designed so that the second bolt-receiving space further includes a second recess in the first outer edge portion of the first fastening projection. The first recess may be located between the second recess and the outer edge of the inner portion of the flange. The provision of this second recess in addition to the first recess may allow positive engagement between the first outer edge portion of the first fastening projection and connecting means located at different distances from the center of the port hole in the end plate.

The second contour portion of the outer contour of the first fastening projection defines a second recess and may have the basic shape of an arc of a circle with radius r2. Radius r2 may or may not be equal to radius r1 described above. This design may allow for a clear and tight engagement between the first outer edge portion of the first fastening projection and connection means, which may be of different sizes and located at different distances from the center of the porthole in the end plate.

The port insert may be configured such that the first fastening projection is provided with a third bolt-receiving space including a third recess in the second outer edge portion of the first fastening projection. The third recess may be designed in a similar manner to the first recess. The provision of the third recess may increase the engagement between the port insert and the connecting means of the plate heat exchanger and/or further increase the number of connection standards compatible with the port insert.

The second outer edge portion may extend from the outer edge of the inner portion of the flange in a direction away from the inner portion. Thus, the first outer edge portion and second outer edge portion described above may extend along each other and be opposing edge portions of the first fastening projection.

The first fastening projection may have an axis of symmetry that coincides with the normal direction of the outer edge of the inner portion.

The third bolt-receiving space may further include a fourth recess in the second outer edge portion of the first fastening projection. The fourth recess may be designed in a similar manner to the second recess.

The port insert may be designed so that the flange further comprises second fastening projections. The second fastening projections may protrude from the annular outer edge of the inner portion to provide the flange with a locally increased width at the second fastening projections. The second fastening projections may be separate from the first fastening projections and designed similarly to the first fastening projections. The first and second fastening projections may be positioned on opposite sides to provide the flange with an axis of symmetry that coincides with the normal direction of the outer edge of the inner portion. Of course, the flange may comprise even further fastening projections, possibly an even number, to allow for flange symmetry. The fastening projections of the flange may be equally spaced along the outer edge of the inner portion.

Further objects, features, aspects and advantages of the present invention will become apparent from the following detailed description and drawings.

The present invention will now be described in more detail with reference to the accompanying schematic diagram.

FIG. 1 is a perspective view of a plate heat exchanger and a filter device. FIG. 10 is a front view of a first port insert of the filter device. FIG. 2b is a cross-sectional/side view of the first port insert of FIG. 2a. FIG. 10 is a front view of a second port insert of the filter device. FIG. 3b is a cross-sectional/side view of the second port insert of FIG. 3a. 3A and 3B are schematic diagrams illustrating engagement positions of fastening projections of a stud bolt. 3A and 3B are schematic diagrams illustrating engagement between a stud bolt and a fastening projection. 10 shows diagrammatically the engagement between two stud bolts and a fastening projection; 10A-10C illustrate diagrammatically the engagement between a flange and various stud bolt configurations.

Figure 1 shows a gasketed plate heat exchanger 2 similar to that described in the introduction. It includes a first end plate 4 and a second end plate 6, referred to as the frame plate and pressure plate, respectively. End plates 4 and 6 are made of carbon steel here, but may be made of any suitable material. End plate 4 has an inner side 8 and an outer side 10 and includes four portholes 12, 14, 16, and 18. Similarly, end plate 6 has an inner side 20 and an outer side 22 and includes four portholes 24, 26, 28, and 30. As shown in Figure 1, end plates 4 and 6 include stainless steel linings for each of portholes 12-30. Additionally, a set of stud bolts 32 are provided for each of portholes 12-30. Stud bolts 32 are fixed to end plates 4 and 6 and protrude normal to the outer sides 10 and 22 of the end plates. The stud bolts 32 in each set are spaced equidistantly around the periphery of the associated porthole and the same distance from the center of the porthole.

The plate heat exchanger 2 further includes a pack of aligned heat transfer plates 34 separated by gaskets (not shown). The pack of heat transfer plates is disposed between end plates 4 and 6, with the end plates and the heat transfer plates 34 extending substantially parallel to each other. One side (not visible) of the pack of heat transfer plates 34, formed by the outer surface of one of the outermost heat transfer plates 34, faces end plate 4, while the other side (not visible) of the pack of heat transfer plates 34, formed by the outer surface of the other outermost one of the heat transfer plates 34, faces end plate 6. Each heat transfer plate 34 includes four portholes (not shown). The portholes in the heat transfer plates 34 extend through the plate pack to form four ports aligned with portholes 12-30 in the end plates 4 and 6. The lower ports, aligned with portholes 16 and 28 in the end plates 4 and 6, respectively, are inlet ports equipped with filter devices 36 (shown separately in FIG. 1). The plate heat exchanger 2 may be equipped with an additional filter device.

The filter device 36 is shown in more detail in Figures 2a and 2b, which show the first port insert 38 of the filter device 36, and in Figures 3a and 3b, which show the second port insert 40 of the filter device 36.

The first port insert 38 comprises a tubular portion 42 and a flange 44, here made of stainless steel but which may be made of any suitable material, such as titanium or SMO. The tubular portion 42 is a cylindrical, perforated tube, and the flange 44 is a plate equipped with an annular inner portion 46 and a greater or lesser number of fastening projections 48, four in this example. The inner portion 46 has an essentially constant width along its annular extension and a circular inner edge 50 having a diameter slightly larger than the outer surface 52 of the tubular portion 42. The flange 44 is welded to the end of the tubular portion 42 and projects perpendicularly from the outer surface 52 of the tubular portion 42. The fastening projections 48 are integrally formed with the inner portion 46 and project from its circular outer edge 54. Furthermore, the fastening projections 48 have a similar design and are equally spaced so that the flanges 44 are symmetrical about two vertical central axes of the flanges 44, each of which extends through two opposing ones of the fastening projections 48.

The second port insert 40 includes a tubular portion 56 and flange 44 designed as described above (even though the flanges 44 of the first and second port inserts 38, 40 have different dimensions). The tubular portion 56 is a pipe with a circular cross section, here made of stainless steel, but which could be made of any suitable material, such as titanium or SMO. The tubular portion 56 is tapered at its free end, thus forming a conical shape. The maximum diameter of the outer surface 58 of the tubular portion 56 is slightly smaller than the diameter of the inner edge 50 of the flange 44 and slightly smaller than the inner diameter of the tubular portion 42 of the first insert 38. The flange 44 is welded to the other end of the tubular portion 56 and projects perpendicularly from the outer surface 58 of the tubular portion 56.

1, 2a, 2b, and 3a, 3b, the first port insert 38 is inserted into the porthole 28 of the end plate 6 and into the corresponding port, such that the tubular portion 42 extends into the port and the flange 44 abuts the porthole gasket (not shown), which in turn abuts the outer side 22 of the end plate 6. Similarly, the second port insert 40 is inserted into the porthole 16 of the end plate 4, such that the tubular portion 56 extends into the port and the flange 44 abuts the porthole gasket (not shown), which in turn abuts the outer side 10 of the end plate 4. When the filter device 36 is properly installed, the tubular portion 56 of the second port insert 40 protrudes further into the tubular portion 42 of the first port insert 38, resulting in overlapping tubular portions 42, 56.

To center the first and second port inserts 38, 40 within the port holes 28, 16 and corresponding ports of the end plates 6, 4, respectively, and attach them to the plate heat exchanger 2, the flange 44 of the first port insert 38 is configured to engage with the stud bolts 32 arranged around the port hole 28, while the flange 44 of the second port insert 40 is configured to engage with the stud bolts 32 arranged around the port hole 16. The engagement between the flange 44 and the stud bolts 32 varies depending on the size, number, and position of the stud bolts, as well as the connection standard of the plate heat exchanger 2.

Figure 4 shows in more detail one of the fastening projections 48 of one of the flanges 44 of the first and second port inserts 38, 40. The fastening projection 48 has an outer contour 60 that defines an extension from the inner portion 46 of the port insert. The boundary between the fastening projection 48 and the inner portion 46 is indicated by a dashed line. The fastening projection 48 is symmetrical about its central axis C, which coincides with one of the central axes of the corresponding flange 44, and about a normal direction N to the outer edge 54 of the inner portion 46. It comprises first and second projections 62, 64, respectively, the boundary between which is defined by the central axis C. The first and second projections 62, 64 are integrally formed near the inner portion 46. They are then separated from each other to form a first bolt-receiving space 66 in the form of a cavity 68, and then rejoined to close the cavity 68.

The cavity 68 has only one axis of symmetry, which coincides with the central axis C. The cavity 68 is elongated, with the longitudinal extension of the cavity 68 measured in the normal direction N and the lateral extension of the cavity 68 perpendicular to the longitudinal extension. As shown in FIG. 4 , the cavity 68 has a shape defined by an outer contour OC of an object formed by a plurality of imaginary circles IC, here five, of different diameters, which are arranged to overlap one another along imaginary straight lines (shown by dashed lines), here coinciding with the central axis C. As a result, the lateral extension of the cavity 68 varies along its longitudinal extension. Each of the imaginary circles IC defines a possible position within the cavity 68 of the stud bolt 32 received in the first bolt-receiving space 66. Because there are five imaginary circles IC of different diameters, the cavity 68 is configured to engage with five stud bolts 32 of different diameters located at five different distances from the center of the porthole in the end plate.

The fastening projection 48 further includes a second bolt-receiving space 70. Similarly, the second bolt-receiving space 70 includes a first recess 72 and a second recess 74 in a first outer edge portion 76 of the fastening projection 48. The first outer edge portion 76 extends from the outer edge 54 of the inner portion 46 of the flange 44, and the first recess 72 is defined between the inner portion 46 and the second recess 74. The first recess 72 is defined by a first contour portion 78 of the outer contour 60 of the fastening projection 48. As shown in FIG. 4, the first contour portion 78 has the shape of an arc of a circle with a first radius r1. The second recess 74 is defined by a second contour portion 80 of the outer contour 60 of the fastening projection 48. As shown in FIG. 4, the second contour portion 80 has the shape of an arc of a circle with a second radius r2. Each of the first recess 72 and the second recess 74 defines a possible position for a stud bolt 32 received within the second bolt-receiving space 70. Because the second radius r2 is greater than the first radius r1, the second recess 74 is adapted to engage with a stud bolt 32 having a larger diameter than the first recess 72. Furthermore, because the second recess 74 is configured outward from the first recess 72, it is adapted to engage with a stud bolt 32 positioned at a greater distance from the center of the porthole in the end plate than a stud bolt 32 positioned to engage with the first recess 72.

The fastening projection 48 further includes a third bolt-receiving space 82. The third bolt-receiving space 82 includes a third recess 84 and a fourth recess 86 on a second outer edge portion 88 of the fastening projection 48. The second outer edge portion 88 faces the first outer edge portion 76 and extends from the outer edge 54 of the inner portion 46 of the flange 44. The third recess 84 and the fourth recess 86 of the third bolt-receiving space 82 correspond to the first recess 72 and the second recess 74 of the second bolt-receiving space 70. The third bolt-receiving space 82 is a mirror image of the second bolt-receiving space 70 along the central axis C of the fastening projection 48. Thus, each of the third and fourth recesses 84, 86 defines a possible position for the stud bolt 32 to be received within the third bolt-receiving space 82, with the fourth recess 86 being adapted to engage a larger diameter stud bolt 32 that is at a greater distance from the porthole center than the third recess 84.

Thus, each of the fastening projections 48 defines a plurality, here nine, of different positions for engaging with stud bolts 32 of different positions and sizes to adapt the first and second port inserts 38, 40 for use with plate heat exchangers of different connection standards.

Figure 5 shows engagement between one of the fastening projections 48 and a stud bolt 32 positioned and sized according to one connection standard, with the stud bolt 32 received in one of five positions within the cavity 68. The diameter of the stud bolt 32 is slightly smaller than the diameter of the imaginary circle IC (Figure 4) that defines the position of the stud bolt 32. The inner edge of the cavity 68 therefore extends opposite the stud bolt 32, close to, and possibly even touching, the stud bolt 32, so that the flange 44 is rotationally and radially locked by the stud bolt 32.

Figure 6 shows engagement between one of the fastening projections 48 and two stud bolts 32, positioned and sized according to another connection standard, received in the first recess 72 and the third recess 84, respectively. The diameter of the stud bolt is slightly less than twice the first radius r1 (Figure 4). The stud bolt 32 is positioned opposite, near, or even in contact with the fastening projection 48, so that the flange 44 is rotationally and radially locked by the stud bolt 32.

Therefore, when the cavity 68 of the fastening projection 48 is used to secure the corresponding flange 44 to one of the end plates 4, 6 of the plate heat exchanger 2, one stud bolt 32 is received in one of five positions within the cavity 68 of the respective fastening projection 48. On the other hand, when the recesses 72, 74, 84, 86 are used to secure the corresponding flange 44 to one of the end plates 4, 6 of the plate heat exchanger 2, two stud bolts 32 are received in one of the first and third recesses 72, 84, respectively, or in one of the second and fourth recesses 74, 86, respectively. Therefore, the flange 44 is adapted for use with a total of seven different stud bolt configurations, i.e., the seven different connection standards of the plate heat exchanger 2 shown in FIG. 7.

In addition to allowing the filter device 36 (Figure 1) to be used with a variety of plate heat exchanger connection standards, the fastening projections 48 make it easy to grasp and pull the first port insert 38 and second port insert 40 of the filter device 36, which may facilitate removal of the filter device 36 from the plate heat exchanger 2, for example, during maintenance.

Consistent with the introduction, at least some of the portholes 12, 14, 16, 18, 24, 26, 28, and 30 in the end plates 4 and 6 of the plate heat exchanger 2 are supply portholes used for supplying fluid to or from the PHE, while the remaining portholes are blind portholes and are not used for supplying liquid. Stud bolts 32, along with appropriate gaskets and nuts, can be used to connect external fluid connections to the supply portholes and blind covers to the blind portholes.

The above-described embodiments of the present invention should be considered as examples only. Those skilled in the art will understand that the described embodiments can be modified in various ways without departing from the concept of the present invention.

As an example, the fastening projections do not all need to be designed the same, and a flange may have more or less than four fastening projections.

The tubular portion of the first port insert does not have to be a cylindrical perforated pipe, but can be formed in any suitable manner, such as a mesh, net, or open filter cloth stretched over a frame.

The fastening projections need not be symmetrical about their respective central axes. Thus, the third bolt-receiving space need not mirror the second bolt-receiving space along the central axis of the corresponding fastening projection. Furthermore, one or both of the second and third bolt-receiving spaces may include three or more recesses.

In the embodiment described above, two stud bolts are received in two opposing recesses when the outer recesses of the fastening projections are used to fasten the corresponding flange to one of the end plates of the plate heat exchanger. In an alternative embodiment, the flange is attached with only one recess and one stud bolt per fastening projection.

The flange does not need to be welded to the tubular portion, but may be attached to the tubular portion in any suitable manner. The flange and tubular portion may also be integrally formed.

Finally, the present invention can be used in combination with other types of plate heat exchangers than those that are purely gasketed, for example, plate heat exchangers with permanently bonded heat transfer plates.

We emphasize here that the attributes primary, secondary, tertiary, etc. are used only to distinguish between similar species and do not express any kind of mutual ordering between species.

Detailed descriptions unrelated to the present invention have been omitted, and it should be emphasized that the drawings are merely schematic and are not drawn to scale. Also, please note that some drawings are simplified more than others. Therefore, some components may be shown in one drawing but omitted in another.

2 Plate heat exchanger 4 First end plate 6 Second end plate 8, 20 Inner side 10, 22, 52, 58 Outer side 12, 14, 16, 18, 24, 26, 28, 30 Port hole 32 Stud bolt 34 Heat transfer plate 36 Filter device 38 First port insert 40 Second port insert 42, 56 Tubular portion 44 Flange 46 Inner portion 48 Fastening projection 50 Inner edge 54 Outer edge 60 Outer contour 62 First projection 64 Second projection 66 First bolt receiving space 68 Cavity 70 Second bolt receiving space 72 First recess 74 Second recess 76 First outer edge portion 78 First contour portion 82 Third bolt receiving space 88 Second outer edge portion 84 Third recess 86 Fourth recess

Claims (12)

A heat exchanger port insert (38, 40) comprising a tubular portion (42, 56) and a flange (44) projecting from an exterior (52, 58) of the tubular portion (42, 56),
The flange (44) comprises an annular inner portion (46) and a first fastening projection (48) having an outer contour (60);
the inner portion (46) includes an annular inner edge (50) where the inner portion (46) joins the tubular portion (42, 56);
the first fastening projection (48) projects from an annular outer edge (54) of the inner portion (46) so as to locally increase the width of the flange (44) at the first fastening projection (48) ;
1. A heat exchanger port insert (38, 40) comprising: a first fastening projection (48) having a second bolt-receiving space (70) including a first recess (72) in a first outer edge portion (76) of the first fastening projection (48). A heat exchanger port insert (38, 40) comprising a tubular portion (42, 56) and a flange (44) projecting from an exterior (52, 58) of the tubular portion (42, 56),
The flange (44) comprises an annular inner portion (46) and a first fastening projection (48) having an outer contour (60);
the inner portion (46) includes an annular inner edge (50) where the inner portion (46) joins the tubular portion (42, 56);
the first fastening projection (48) projects from an annular outer edge (54) of the inner portion (46) so as to locally increase the width of the flange (44) at the first fastening projection (48) ;
The first fastening projection (48) includes a first bolt receiving space (66);
the first fastening projection (48) branches into a first protruding portion (62) and a second protruding portion (64) extending in a direction away from the inner portion (46) of the flange (44), and the first bolt-receiving space (66) comprises a cavity (68) defined by the first protruding portion (62) and the second protruding portion (64);
A heat exchanger port insert (38, 40) characterized in that said cavity (68) has less than two axes of symmetry . The heat exchanger port insert (38, 40) of claim 2 , wherein the cavity (68) has a finite number of axes of symmetry. 4. The heat exchanger port insert (38, 40) of claim 2 or 3, wherein a longitudinal extension of the cavity (68) measured in a normal direction (N) of the annular outer edge (54) of the inner portion (46) passing through a center of the cavity (68) is greater than a lateral extension of the cavity (68), and the lateral extension of the cavity ( 68 ) is perpendicular to the longitudinal extension of the cavity (68). The heat exchanger port insert (38, 40) of claim 4 , wherein the lateral extension of the cavity (68) varies along the longitudinal extension of the cavity (68). 4. The heat exchanger port insert (38, 40) according to claim 2 or 3, wherein the shape of the cavity (68) is defined by an outer contour (OC) of an object formed by a plurality of imaginary circles (IC) of different diameters, the imaginary circles (IC) being aligned along an imaginary straight line (I), and two adjacent imaginary circles (IC) partially overlapping each other. 2. The heat exchanger port insert (38, 40) of claim 1 , wherein the first outer edge portion (76) extends from the annular outer edge (54) of the inner portion (46) of the flange (44) in a direction away from the inner portion (46). 2. The heat exchanger port insert (38, 40) of claim 1, wherein a first contour portion (78) of the outer contour (60) of the first fastening projection (48) defines the first recess (72) and has a basic shape of an arc of a circle having a first radius ( r1 ). 2. The heat exchanger port insert (38, 40) of claim 1 , wherein the second bolt receiving space (70) comprises a second recess (74) in a first outer edge portion (76) of the first fastening projection (48). 2. The heat exchanger port insert (38, 40) of claim 1, wherein the first fastening projection (48) has a third bolt-receiving space (82) including a third recess (84) in a second outer edge portion (88) of the first fastening projection (48). 11. The heat exchanger port insert (38, 40) of claim 10 , wherein the second outer edge portion (88) extends from the annular outer edge (54) of the inner portion (46) of the flange (44) in a direction away from the inner portion (46). 4. The heat exchanger port insert (38, 40) of claim 2 or 3, wherein the flange (44) further comprises a second fastening projection (48) protruding from the annular outer edge (54) of the inner portion (46) and locally increasing the width of the flange (44) at the second fastening projection (48).