WO2014173608A1

WO2014173608A1 - A device for supporting a heat transfer plate and a heat transfer plate provided with such a device

Info

Publication number: WO2014173608A1
Application number: PCT/EP2014/056106
Authority: WO
Inventors: Anders Nyander
Original assignee: Alfa Laval Corporate Ab
Priority date: 2013-04-23
Filing date: 2014-03-27
Publication date: 2014-10-30
Also published as: EP2796824A1; EP2796824B1; DK2796824T3; PL2796824T3; ES2708395T3

Abstract

A device (2, 80) for supporting a heat transfer plate (46) between two end plates (66, 68) in a plate heat exchanger (64), and a heat transfer plate fitted with such a device, are provided. The device is at least partly is made of a polymeric material. The device comprises first means (10, 12, 14, 30, 32, 34, 88, 90) for achieving engagement between the heat transfer plate and the device and second means (36, 78, 86) for engagement with a bar (70, 72) extending between the two end plates. The device is characterized in that said second means includes a cavity (36, 86) arranged to receive the bar.

Description

A DEVICE FOR SUPPORTING A HEAT TRANSFER PLATE AND A HEAT TRANSFER PLATE PROVIDED WITH SUCH A DEVICE

TECHNICAL FIELD

The invention relates to a device for supporting a heat transfer plate between two end plates in a plate heat exchanger, which device at least partly is made of a polymeric material. The invention also relates to a heat transfer plate provided with such a device.

BACKGROUND ART

Plate heat exchangers (PHEs) typically consist of two end plates in between which a number of heat transfer plates are arranged in an aligned manner in a plate package. In one type of well-known PHEs, the so called gasketed PHEs, gaskets are arranged between the heat transfer plates. The end plates, and therefore the heat transfer plates, are pressed towards each other whereby the gaskets seal between the heat transfer plates. The gaskets define parallel flow channels between the heat transfer plates through which channels two fluids of initially different temperatures alternately can flow for transferring heat from one fluid to the other.

Typically, a PHE comprises an upper carrying bar and a lower guiding bar extending in parallel between the end plates. Further, the heat transfer plates may each be provided with an upper cut-out at its upper short side and a lower cut-out at its lower short side, which upper and lower cut-outs engage with the carrying bar and the guiding bar, respectively, when the heat transfer plates are mounted in the PHE. One purpose of the carrying and guiding bars is to align the heat transfer plates properly in the plate package. Another purpose of the carrying bar is, as the name implies, to carry the plate package and the media enclosed therein during operation of the PHE in that the heat transfer plates are arranged to be suspended from the carrying bar.

To prevent deformation of the cut-outs due to the engagement with the carrying and guiding bars, especially larger heat transfer plates are often provided with reinforcements in the areas of the cut-outs. Typically, the reinforcements are metal sheets provided with a respective cut-out, which metal sheets are fastened to the heat transfer plates with their cut-outs aligned with the heat transfer plates cut-outs.

The reinforcements are typically fastened to the heat transfer plates in a robot station by spot welding. In order to make sure that the reinforcements are properly placed onto the heat transfer plates prior to welding, the robot station comprises relatively complex vision and fixation systems. Further, the equipment for the spot welding is expensive and requires maintenance and surveillance. Thus, the provision of reinforcements onto the heat transfer plates is associated with relatively high costs without addition of any further value to the PHE end product than prevention of deformation of the heat transfer plates.

SUMMARY

An object of the present invention is to provide a device for strong, form stable engagement between a heat transfer plate and a bar in a PHE, which device easily may be configured to give additional functionality to the PHE. Another object of the present invention is to provide a heat transfer plate comprising such a device. The device and the heat transfer plate for achieving the objects above are defined in the appended claims and discussed below.

A device according to the present invention is arranged to support a heat transfer plate between two end plates in a plate heat exchanger. The device is at least partly made of a polymeric material. It comprises first means for achieving engagement between the heat transfer plate and the device and second means for engagement with a bar extending between the two end plates. The device is characterized in that said second means includes a cavity arranged to receive the bar.

By support is meant any type of engagement. Thus, the device may be arranged to carry and/or guide the heat transfer plate. Accordingly, the bar may be a carrying bar and/or a guiding bar like the above mentioned ones.

The bar can be of different kinds. For example, it may be formed as a rail, a rod, a beam, etc.

Since the device at least partly is made of a polymeric material, which relatively easy can be formed into essentially any shape, the design of the device is very flexible. Thereby, that the device may, in a neat way, be adapted to perform other functions than just engaging the heat transfer plate and the bar. Examples of this will be given later on in the description.

In that the second means for engagement with the bar comprises a cavity arranged to receive the bar, a stable and mechanically simple design of the device is enabled. In case the second means are made of the polymeric material they may easily be given a design adapted to the shape of the bar.

The first means may be arranged to dismountably or removably attach the device to the heat transfer plate. Such an embodiment may enable a mechanical, non-permanent engagement between the device and the heat transfer plate allowing non-destructive, repeated application and removal of the device. Examples of permanent engagement methods are welding and brazing. Further, such a dismountable attachment may enable application and removal of the device without complex and expensive equipment, like the robot station referred to above.

The device may comprise a first part arranged to engage with a first side of the heat transfer plate, the first means including a primary projection being comprised in the first part. By the first part comprising a primary projection, a strong and stable engagement between the heat transfer plate and the device can be obtained.

The primary projection may be arranged to be received in a hole of the heat transfer plate which enables a strong and stable engagement between the device and the heat transfer plate. Further, this enables an easy and precise positioning of the device onto the heat transfer plate without the use of a complex vision system. Further, the primary projection may be arranged to be snap locked in the hole of the heat transfer plate. Thereby, the device may be applied onto/removed from the heat transfer plate in a simple, fast and reliable manner without the use of complex special equipment.

The device may further comprise a second part arranged to engage with a second opposing side of the heat transfer plate. Such an embodiment enables "clipping" of the heat transfer plate between the first and second parts of the device which, in turn, may enable a firm and safe engagement between the heat transfer plate and the device.

The first and second parts of the device may be connected by a joint. Such a design may render the device particularly neat to apply onto the heat transfer plate and neat to handle in that the device may comprise one single article.

The first and second parts of the device may be arranged to, individually or jointly, engage with the heat transfer plate and/or with each other.

Accordingly, the first means may include a primary void comprised in the second part of the device and being arranged to receive the primary projection comprised in the first part of the device. The primary projection may or may not be arranged to extend through the heat transfer plate. Further, the primary projection may be arranged to be snap-locked in the primary void. Thereby, the device may be applied onto/removed from the heat transfer plate in a simple, fast and reliable manner without the use of complex special equipment.

The first means may further include a secondary projection comprised in one of the first and second parts, and a secondary void comprised in the other one of the first and second parts, which secondary projection and secondary void are arranged for mutual engagement and arranged to be positioned at least partly outside the heat transfer plate. Such an embodiment may enable an even stronger engagement between the heat transfer plate and the device.

The second means for engagement with the bar may be arranged to be positioned partly or completely outside the heat transfer plate. In accordance herewith, the heat transfer plate may lack an indentation for engagement with the bar and the bar may be arranged outside the heat transfer plate in the plate heat exchanger, which may result in that a larger surface of the heat transfer plate is available for heat transfer.

The device may further comprise third means for engagement with another similar device. The purpose of such engagement may for example be heat transfer plate alignment, as will be further described below.

A heat transfer plate according to the present invention is provided with a device according to the above. Still other objectives, features, aspects and advantages of the invention will appear from the following detailed description as well as from the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail with reference to the appended schematic drawings, in which

Fig. 1 a is a plan view of a device for supporting a heat transfer plate in a plate heat exchanger,

Fig. 1 b is a side view of the device of Fig. 1 a,

Fig. 1 c contains a cross sectional view of the device of Fig. 1 a,

Fig. 2 is a plan view schematically illustrating a heat transfer plate, Fig. 3 contains a plan view of the heat transfer plate of Fig. 2 provided with devices according to Figs. 1 a and 1 b,

Fig. 4 is a schematic side view of a plate heat exchanger,

Fig. 5 contains a cross sectional view of a plurality of heat transfer plates provided with devices according to Figs. 1 a and 1 b,

Fig. 6a is a plan view of a device according to an alternative embodiment of the invention,

Fig. 6b is a side view of the device of Fig. 6a,

Fig. 6c contains a cross sectional view of the device of Fig. 6a,

Fig. 6d is a plan view of the device of Fig. 6a in a closed state,

Fig. 7 is a plan view of a device according to an alternative embodiment of the invention, and

Fig. 8 is a plan view of a device according to yet an alternative

embodiment of the invention.

DETAILED DESCRIPTION

Figs. 1 a-c illustrate a device 2 made by injection molding of a

thermoplastic polymeric material in the form of polypropylene, PP. The device 2 has an open state illustrated in Figs. 1 a and 1 b and a closed state illustrated in Fig. 1 c. The device 2 comprises a first part 4 and a second part 6 which are connected by a joint 8 formed by a portion of the device having a thinner material thickness. The first part 4 of the device 2 comprises a primary projection 10, and two similar secondary projections 12 and 14, which projections extend from an inside 16, and in a normal direction, of the first part 4. The primary projection 10 has the shape of a truncated arrow with a shaft 18 and a head 20, and it is formed of four primary fingers 22. The fingers 22 are resilient and may be brought into contact with each other from a default state in which they are separated from each other to enable variation of the outer dimensions of the primary projection 10. Each of the secondary projections 12 and 14 has the shape of a truncated arrow with a shaft 24 and a head 26, and it is formed of four secondary fingers 28. The fingers 28 are resilient and may be brought into contact with each other from a default state in which they are separated from each other to enable variation of the outer dimensions of the secondary projections 12 and 14. The second part 6 comprises a primary void 30, and two similar secondary voids 32 and 34, all voids being formed as through holes in the second part of the device. The primary and secondary projections and voids 10, 12, 14, 30, 32 and 34 are also together referred to herein as first means.

Further, the device 2 is provided with a centrally arranged through cavity 36 which is symmetric with reference to the joint 8. As will be further discussed below, the cavity 36 is arranged to enable engagement between the device 2 and a bar of a plate heat exchanger. The cavity 36 is also referred to herein as second means.

Furthermore, the first part 4 of the device 2 is provided with a primary dent 38 and two similar secondary dents 40 and 42 extending from an outside 44 of the first part 4. The primary and secondary dents 38, 40 and 42 are aligned with the primary and secondary projections 10, 12 and 14, respectively, and they can be seen in Fig. 1 c where the secondary dents have been illustrated with ghost lines since they are not in reality visible in this view. The head 20 of the primary projection 10 fits into the primary dent 38 when the fingers 22 are in the default state. Similarly, the head 26 of each of the secondary projections 12 and 14 fits into the respective secondary dent 40 and 42 when the fingers 28 are in the default state. The primary and secondary dents 38, 40 and 42 are also referred to herein as third means.

Fig. 1 c is a cross sectional view of the device of Fig. 1 a, taken along the line A-A, when the device is in its closed state and in engagement with a heat transfer plate 46 (of which only a portion is visible). To accommodate the heat transfer plate 46, a first portion 4a of the first part 4, comprising the primary projection and dent, has a reduced thickness t-i , through an inside depression 48 of the first part 4, as compared to a second portion 4b of the first part 4, comprising the secondary projections and dents, which has a thickness t₂. Similarly, a first portion 6a of the second part 6, comprising the primary void, has a reduced thickness t-i , through an inside depression 50 of the second part 6, as compared to a second portion 6b of the second part 6, comprising the secondary voids, which has a thickness t₂. In the space formed between the first portions 4a and 6a of the first and second parts 4 and 6 of the device 2 when this is in the closed state, the heat exchanger plate 46 is arranged to be received. More particularly, the first portion 4a of the first part 4 is arranged to engage with a first side 52 of the heat transfer plate while the first portion 6a of the second part 6 is arranged to engage with a second side 54 of the heat transfer plate.

The heat transfer plate 46 is schematically illustrated in Fig. 2. It is essentially rectangular, made of stainless steel and partly provided with a corrugation pattern of ridges and valleys, as is conventional, although not illustrated. The heat transfer plate comprises two through holes 56 and 58 arranged close to a respective short side 60 and 62 thereof, which holes are centered in relation to a longitudinal heat transfer plate center axis C. The holes are arranged for engagement with a respective device 2 to secure this to the heat transfer plate 46, as is illustrated in Fig. 1 c and Fig. 3. More particularly, each of the devices is folded along the joint 8 around an edge of the respective heat transfer plate short side 60, 62 such that the primary projection 10 is inserted through the respective hole 56, 58. During closing of the device, the primary projection 10 is further inserted into the primary void 30 while the secondary projections 12 and 14 are inserted into the secondary voids 32 and 34.

The sizes of each of the heat transfer plate holes 56 and 58 and the primary void 30 are such that the head 20 of the primary projection 10 narrowly can be forced through the heat transfer plate 46 and the primary void 30 when the primary fingers 22 are in maximum contact with each other, i.e. when the head 20 is as small as possible. Further, the shaft 18 of the primary projection 10 is just slightly longer than the thickness ti of the first portion 6a of the device plus a "thickness" or an extension of the heat transfer plate in direction perpendicular to the figure plane of Fig. 2. Thereby, when the device is completely closed around the heat transfer plate, the head 20 of the primary projection protrudes from an outside 60 of the second part 6 of the device.

Further, the fingers 22 of the primary projection 10 are in the default state so as to keep the device closed. Similarly, the size of the secondary voids 32 and 34 is such that the head 26 of the secondary projections 12 and 14 narrowly can be forced through the secondary voids when the secondary fingers 24 are in maximum contact with each other, i.e. when the head 26 is as small as possible. Further, the shaft 24 of the secondary projections is just slightly longer than the thickness t₂ of the second portion 6b of the device. Thereby, when the device is completely closed around the heat transfer plate, the head 26 of the secondary projections protrudes from the outside 60 of the second part 6 of the device. Further, the fingers 28 of the secondary projections are in the default state so as to keep the device closed. Thus, the primary and secondary projections and voids are pair-wise cooperating snap-locking means enabling locking when the fingers are in the default state and releasing when the fingers are in maximum contact with each other. The device-heat transfer plate engagement is wholly mechanical and a device may be repeatedly and indestructibly fastened to, and removed from, a heat transfer plate manually and without the use of complex special tools and expensive equipment. This means that a device easily can be replaced if necessary, for instance if it breaks. The device is easily fastened to the heat transfer plate by folding the device along the joint and around the edge of the plate and pressing the first and second parts of the device against each other. In connection therewith, the fingers of the projections are automatically forced together when the heads of the projections are forced through the respective voids. When the heads of the projections have passed the respective voids, the fingers take their default position to lock the device to the heat transfer plate. The device is loosened from the heat transfer plate by forcing together the fingers of the projections for un-locking and separating the first and second parts of the device. Naturally, automated application and/or removal of the device onto/from the heat transfer plate may also be possible.

Fig. 4 schematically illustrate a plate heat exchanger 64 comprising two end plates 66 and 68 in between which an upper carrying bar 70 and a lower guiding bar or guiding rail 72 of stainless steel extend in parallel. The plate heat exchanger 64 further comprises a number of heat transfer plates 46 arranged in a plate pack 74, which heat transfer plates are separated by gaskets (not illustrated). Each of the heat transfer plates 46 is provided with two devices 2 as is illustrated in Fig. 3 - one device 2' arranged for engagement with the carrying bar 70 and one device 2" arranged for engagement with the guiding rail 72. It should be stressed that the devices 2' and 2" here are similar and that the prim (') and bis (") notations are used only to indicate engagement with either the carrying bar or the guiding rail.

The heat transfer plates 46 are arranged to hang from the carrying bar 70 which consequently is arranged to carry the plate pack 74. As is clear from Fig. 3, the carrying bar 70 is arranged to be received in the cavities 36 of the devices 2'. Accordingly, the cross section of the carrying bar 70 is adapted to the cavity form such that the devices 2' cannot be separated from the carrying bar 70 when this is inserted through cavities 36 of the devices, i.e. the devices 2' and the carrying bar 70 are "self-locking". Further, the heat transfer plates 46 are arranged to be guided by the guiding rail 72. As is clear from Fig. 3, the devices 2" are arranged to be received between two shanks 76 of the guiding rail 72. Accordingly, the distance between the shanks 76 is just slightly larger than the distance between two opposing guiding edges 78 of the devices 2", i.e. a width of the devices 2". The guiding edges 78 of the devices 2 are, together with the cavities 36, also referred to herein as second means.

The plate heat exchanger illustrated in Fig. 4 comprises further components, like bolts, nuts and connections, which components, however, are not relevant to the invention and thus not illustrated or further described herein.

Fig. 5 is a cross sectional view (corresponding to that of Fig. 1 c) partially illustrating three plates of the plate pack 74 and the associated devices 2, here denoted 2a, 2b and 2c. As is clear from the figure, the devices of adjacent plates are arranged to engage with one another. More particularly, the primary projection 10a of the device 2a is arranged to be received in the primary dent 38b of the device 2b while the secondary projections, only the one denoted 12a illustrated, with ghost lines, in the figure, of the device 2a is arranged to be received in the secondary dents, only the one denoted 40b illustrated, with ghost lines, in the figure, of the device 2b. The device 2b is arranged to engage with the device 2c in a corresponding way, etc. Thus, the primary and secondary projections of one device cooperate with the primary and secondary dents of an adjacent device so as to achieve alignment of the devices and thus the associated heat transfer plates. Since all the heat transfer plates 46 are provided with devices 2, an alignment of the complete plate pack 74 may be obtained in the plate heat exchanger 64. Thus, further measures for aligning the heat transfer plates may be unnecessary. Thereby, the need for tight tolerances between the carrying bar and/or the guiding bar and the devices for supporting the heat transfer plates in the plate heat exchanger may be alleviated. Also, guiding means, such as guiding corners, of the heat transfer plates for mutual alignment of the heat transfer plates may be unnecessary. Properly aligned heat transfer plates essentially reduces the risk of leakage from the plate heat exchanger.

As mentioned above, the heat transfer plates 46 are each partly provided with a corrugation or pattern of ridges and valleys even if they, for the sake of simplicity, have been illustrated as plane sheets in the drawings. The heat transfer plates 46 are here all of the same kind. Inside the plate heat exchanger 64 when this is ready for use, every second heat transfer plate is rotated, in relation to a reference orientation, 1 80 degrees around an axis x in a direction D (Fig. 2) and the valleys of one heat transfer plate abut against the ridges of an underlying heat transfer plate while the ridges of said one heat transfer plate abut against the valleys of an overlying heat transfer plate. In the areas of the heat transfer plates arranged for engagement with the devices, there is typically no corrugation. Instead, the heat transfer plates are plane within these areas. As is apparent from Fig. 5, the heat transfer plates are separated by a distance d within these areas. The devices are so dimensioned as to fill up the space between the heat transfer plates within these areas, i.e. ti =612. Thereby, the devices 2 function as supports or distance means between the heat transfer plates.

Several features and advantages are obtainable by a device according to the present invention. For example, since the devices are made of a polymer they can easily be provided in different colors to enable simple color coding. A certain color of the device could, as an example, be used to indicate a certain type of heat transfer plate, such as a heat transfer plate with a certain pattern. Also, the device can easily be given an infinite number of different designs. This increases the flexibility of the design of other parts of the plate heat exchanger, e.g. the carrying bar and the guiding bar/rail.

The above described embodiment of the present invention should only be seen as an example. A person skilled in the art realizes that the embodiment discussed can be varied in a number of ways without deviating from the inventive conception.

For example, in the above described embodiment the second means of the device, i.e. the cavity 36 and the guiding edges 78 for engagement with the carrying bar and guiding bar/rail are arranged to be positioned outside the heat transfer plate pack. One advantage of this configuration is that it may result in a larger heat transfer plate surface available for the very heat transfer. However, the second means of the device could instead be arranged to be positioned within the heat transfer plate pack like the conventional metal sheets provided with cut-outs mentioned by way of introduction. Thus, according to an alternative embodiment of the invention the device may be arranged to at least partly enclose an indentation or hole of the heat transfer plate, which

indentation or hole is arranged to receive a carrying or guiding bar extending between the end plates. Accordingly, the device may comprise a cut-out or cavity arranged to be aligned with the indentation or hole of the heat transfer plate, which cut-out or cavity may, or may not, be arranged to be edge-to-edge with the heat transfer plate indentation or hole. Such an embodiment could enable for the device to work as a reinforcement to prevent deformation of the heat transfer plate in an area of engagement with a bar to support the heat transfer plate inside a plate heat exchanger.

As another example, the devices could be provided with means for snap- locking of adjacent devices. Such an embodiment could enable assembly, even outside the plate heat exchanger, of several heat transfer plates into a partial plate pack by the respective devices of the heat transfer plates being snap- locked to each other. This could facilitate assembly of the complete plate heat exchanger since such partial plate packs may be less prone to flexing than individual heat transfer plates which may facilitate the arrangement of the heat transfer plates between the end plates of the plate heat exchanger. Moreover, in such partial plate packs the gaskets may be fixed between adjacent heat transfer plates so as to not be dislocated in connection with being arranged between the end plates of the plate heat exchanger. Further, in the above described embodiment, the weight of the plate pack is carried by the carrying bar, which is supported by the end plates, since the individual heat transfer plates are too flexible to maintain upright when standing and therefore must be hung. To prevent deformation of the carrying bar, this must be relatively strong which makes it relatively expensive. A device design with snap-locking functionality between adjacent devices could make the plate pack rigid enough to support itself and remain upright when standing. That opens up a possibility of a plate heat exchanger with a lower carrying bar or carrying rail and an upper guiding bar or guiding rail, i.e. a possibility of the heat transfer plates resting on the lower bar or rail instead of hanging from the upper bar. The lower carrying bar or rail could be supported directly by the floor which could enable a more lean design of large parts of the plate heat exchanger. For example, the end plates could be made relatively lean just like the upper bar or rail.

In the embodiment described above and illustrated in the figures, the holes of the heat transfer plate are larger than the head of the primary projections when this is as small as possible. When the device is properly attached to the heat transfer plate, the shaft of the primary projections runs through the holes of the heat transfer plate. Since the holes of the heat transfer plate are considerably larger than the shaft of the primary projections, there is a "play" between the heat transfer plate and the device, or more particularly, the primary projection thereof. In view of this, the device could further be provided with a positioning means arranged specifically for the very positioning of the device in relation to the heat transfer plate. Such a positioning means could be formed as a positioning projection extending from the inside, and in a normal direction, of the first part of the device and arranged to be received in a positioning hole of the heat transfer plate. The positioning projection could, but doesn't have to, be arranged to be received in a corresponding positioning void in the second part of the device. The size and form of the positioning projection and the positioning hole should be such that there is essentially no play between them when the device is properly attached to the heat transfer plate. Above, the projections of a device cooperate with the dents of a most adjacent device for alignment of the two devices. A device could be configured to not only cooperate with a most adjacent device but also a second most, a third most, etc., adjacent device for alignment of these devices.

The primary projection of the device need not be arranged to snap-lock in the heat transfer plate. According to an alternative embodiment of the invention, the holes of the heat transfer plate are larger than the head of the primary projection in the default state.

The form, number and positioning of the projections, voids and dents of the devices need not be as above described but can be varied endlessly.

Accordingly, the projections, voids and dents can be arranged to engage with each other in other ways than by snap-locking. Accordingly, instead of comprising a centrally arranged pair of primary projection and primary void like above described, which primary projection is arranged to engage with a centrally arranged hole of the heat transfer plate, the device could comprise two pairs of primary projection and primary void, arranged centrally or non-centrally, which primary projections could be arranged to engage with a respective hole of the heat transfer plate. Such a design could enable a more stable engagement between the device and the heat transfer plate. Further, the form and number of fingers of the projections can be varied in many ways.

Further, the form and positioning of the cavity of the devices need not be as above described but can be varied in many ways. For example, the cavity need not be symmetric with reference to the joint between the first and second parts of the device. In Figs. 6a-6d a device 80 according to an alternative embodiment of the invention is illustrated. Hereinafter, in discussing details that are similar for the devices 2 and 80, the reference numerals of Figs. 1 -5 are used. Further, details that are similar for the devices 2 and 80 are not again described in detail or not described at all. The device 80 comprises a primary projection 10 and a primary void 30. Further, the first part 4 of the device 80 comprises an elongate protrusion 82 extending from an inside 16, and in a normal direction, of the first part 4 and along an edge 84 of a cavity 86 provided in the device. The protrusion 82 has an elongate secondary void 88 extending along the edge 84 of the cavity 86. Further, the second part 6 of the device 80 comprises a secondary projection 90 extending in a direction perpendicular to a normal direction of the second part. When the device 80 is in its closed state, the secondary projection 90 is arranged to be received and snap-locked in the secondary void 88. As is clear from Figs. 6c and 6d, a surface 92 arranged to face a carrying bar will be formed in one single piece by the first part 4 of the device 80 only, i.e. it will not comprise a joint between the first and second parts, which is the case with the device 2. This may result in reduced slide friction between the device and the carrying bar. Naturally, the device could be provided with similar snap-lock means along some/all of edges 92, 94, 96, 98, 100, 102, 104, 106 and 108.

Fig. 7 illustrates a device 1 10 according to yet an alternative embodiment of the invention. Like above, in discussing details that are similar for the devices 2 and 1 10, the reference numerals of Figs. 1 -5 are used. Further, details that are similar for the devices 2 and 1 10 are not again described in detail or not described at all. The device 1 10 comprises first and second parts of which only the first part, denoted 1 12, is visible in Fig. 7 which illustrates the device 1 10 in a closed state. The first and second parts are connected by a joint 8. The device 1 10 is provided with a centrally arranged cavity 1 14 which is symmetric with reference to the joint 8. Since the device 1 10 is shown in its closed state in Fig. 7, only half of the cavity 1 14 is illustrated. The device 1 10 is adapted to be used, when arranged at an upper short side of a heat transfer plate, with a carrying bar (not illustrated) with a circular cross section, which carrying bar then is received in, more particularly inserted through, the cavity 1 14. If the diameter of the carrying bar is sufficient, the carrying bar will be locked in the cavity 1 14 and it will be possible for the device 1 10, and thus the heat transfer plate, to hang from the carrying bar. Accordingly, the cavity 1 14 has a design adapted to a carrying bar with a circular cross-section. Naturally, the device 1 10 could also be arranged at a lower short side of a heat transfer plate and be arranged to receive, in its cavity 1 14, a guiding bar which could have a circular cross section, or be arranged to engage with a guiding rail like the guiding rail 72 illustrated in Fig. 3.

The first and second parts of the device could be arranged to engage with each other in many different ways. As an example, the first and second parts could be chemically or permanently connected, such as by welding or gluing, which could make the device a single-use article.

The device could be arranged to engage with one side only of the heat transfer plate. As an example, the device could comprise a first part only arranged to be snap-locked in the heat transfer plate only. Naturally, such a single part device could be arranged to engage with the heat transfer plate in other ways than by snap-locking, e.g. by gluing or welding. Fig. 8 illustrates a device 1 16 according to yet an alternative embodiment of the invention. The device 1 16 comprises a first part 1 18 only, arranged to engage (no engagement means illustrated) with one side only of a heat transfer plate. The device 1 16 is provided with a centrally arranged cavity 120. The design of the cavity 120 is such that the device 1 16 is adapted to be used with a bar (not illustrated) with a circular cross section, which bar then is received in the cavity 120. Irrespective of the diameter of the bar, the bar will not be locked in the cavity 120 since an edge 122 defining the cavity extends less than 180 degrees around. Hence, it will not be possible for the device 1 16, and thus the heat transfer plate, to hang from the bar. Thus, a heat transfer plate provided with the device 1 16 at its upper short side is typically supported from below, i.e. at its lower short side, by a lower bar, and just guided at its upper short side. Naturally, a heat transfer plate could be provided with a device 1 16 at one or both of the upper and lower short sides. Further, the device 1 16 could be arranged to engage with a rail similar to the one illustrated in Fig. 3 instead of a bar, both when arranged at the upper and the lower short side of a heat exchanger plate.

Naturally, also a device comprising first and second parts arranged to engage with one side each of a heat transfer plate could be formed so as to not interlock with a bar. As an example, such a two-part device could comprise a cavity arranged to extend less than 180 degrees around a bar, like the cavity 120.

The device could be arranged to engage with a heat transfer plate without the above described hole by only surface-to-surface friction. In such an embodiment, some kind of friction increasing agent or means could be used between the device and the heat transfer plate.

The device could be formed in other thermoplastic materials than PP, and also in a thermosetting plastic material instead of a thermoplastic material. For example, the device could alternatively be formed in high-density

polyethylene, polyamide and/or polyphenylensulfid, or of some kind of high- performance polymeric material like polyether ether ketone (PEEK) or similar. Also, the device could be formed through other techniques than injection molding, e.g. thermoset molding, thermoforming, compression molding, vacuum forming or 3D printing.

In the above described embodiment, each of the heat transfer plates are provided with two devices, which devices are oppositely arranged on the short sides of the heat transfer plates. Naturally, each of the heat transfer plates could be provided with more or less than two devices and the devices could be arranged in alternate locations on the heat transfer plates.

The projections and voids need not all be provided in the first and the second parts, respectively, of the device. Each of the first and second parts could comprise at least one of the projections and at least one of the voids of the device.

The above described device comprises a first and a second part having a respective depression for housing the heat transfer plate. Naturally, only one of the first and second parts could alternatively be provided with a deeper depression for housing the heat transfer plate. Such a device could be easier to manufacture.

The device may be made entirely of one or more polymeric materials or it may partly comprise other materials, such as metallic reinforcement elements, possibly molded-in, if suitable. The polymeric material of which the device is made may further comprise different types of additives for providing the device with specific characteristics. As an example, magnetic particles could be added to the polymeric material to make the device magnetic.

Instead of an upper carrying bar and a lower guiding rail which are different from each other, the PHE could comprise similar upper and lower rails or bars.

Finally, the present invention could be used in connection with other types of plate heat exchangers than gasketed ones, such as plate heat exchangers comprising permanently joined heat transfer plates.

It should be stressed that the attributes first, second, third, etc. is used herein just to distinguish between species and not to express any kind of mutual order between the species.

It should be stressed that a description of details not relevant to the present invention has been omitted and that the figures are just schematic and not drawn according to scale. It should also be said that some of the figures have been more simplified than others. Therefore, some components may be illustrated in one figure but left out on another figure.

Claims

1 . A device (2, 80) for supporting a heat transfer plate (46) between two end plates (66, 68) in a plate heat exchanger (64), which device at least partly is made of a polymeric material and comprises first means (10, 12, 14, 30, 32, 34, 88, 90) for achieving engagement between the heat transfer plate and the device and second means (36, 78, 86) for engagement with a bar (70, 72) extending between the two end plates, characterized in that said second means includes a cavity (36, 86) arranged to receive the bar.

2. A device (2, 80) according to claim 1 , wherein the first means (10,

12, 14, 30, 32, 34, 88, 90) are arranged to dismountably attach the device to the heat transfer plate (46).

3. A device (2, 80) according to any of the preceding claims, comprising a first part (4) arranged to engage with a first side (52) of the heat transfer plate (46), the first means (10, 12, 14, 30, 32, 34, 88, 90) including a primary projection (10) being comprised in the first part.

4. A device (2, 80) according to claim 3, wherein the primary projection (10) is arranged to be received in a hole (56, 58) of the heat transfer plate (46).

5. A device (2, 80) according to claim 4, wherein the primary projection (10) is arranged to be snap locked in the hole (56, 58) of the heat transfer plate

(46).

6. A device (2, 80) according to any of claims 3-5, further comprising a second part (6) arranged to engage with a second opposing side (54) of the heat transfer plate (46).

7. A device (2, 80) according to claim 6, further comprising a joint (8) connecting the first and second parts (4, 6).

8. A device (2, 80) according to any of claims 6 or 7, wherein the first means (10, 12, 14, 30, 32, 34, 88, 90) includes a primary void (30) comprised in the second part (6) and being arranged to receive the primary projection (10) comprised in the first part (4).

9. A device (2, 80) according to claim 8, wherein the primary projection (10) is arranged to be snap-locked in the primary void (30).

10. A device (2, 80) according to any of claims 6-8, wherein the first means (10, 12, 14, 30, 32, 34) further includes a secondary projection (12, 14, 90) comprised in one of the first and second parts (4, 6), and a secondary void (32, 34, 88) comprised in the other one of the first and second parts, which secondary projection and secondary void are arranged for mutual engagement and arranged to be positioned at least partly outside the heat transfer plate (46).

1 1 . A device (2, 80) according to any of the preceding claims, wherein the second means (36, 78, 86) for engagement are arranged to be positioned at least partly outside the heat transfer plate (46).

12. A device (2, 80) according to any of the preceding claims, further comprising third means (38, 40, 42) for engagement with another device according to any of the preceding claims.

13. A heat transfer plate (46) provided with a device (2, 80) according to any of the preceding claims.