GB1603362A - Temperature regulating heating or cooling means incorporating an indented wall - Google Patents

Description

(54) TEMPERATURE REGULATING, HEARING OR COOLING MEANS INCORPORATING AN INDENTED WALL (71) We, G. U. ENGINEERING LIMITED, a British company, of Coppermill Court, West Hyde, Rickmansworth, Hertfordshire, WD3 2XS (formerly of Maple Cross, Denham Way, Rickmansworth, Hertfordshire WD3 2RS), do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement :- This invention relates to temperature regulating, heating or cooling means which may be supplied with fluid at desired temperatures to perform the desired temperature regulating, heating or cooling function.

In our co-pending Applicaton No.

24996/76 (1,582,836) there is described and claimed a vessel having a jacket adjoining a wall thereof, a chamber for a temperature controlling fluid being defined between the jacket and the wall of the vessel, an inlet and an outlet to said chamber being provided in the jacket and a flow guiding member being disposed within said chamber between the jacket and the wall of the vessel for guiding the flow of fluid in the course of its passage through the chamber from the inlet to the outlet, the vessel wall being of sheet metal in the form of a metal sheet spaced from the vessel wall over the major part of the area of the jacket, the jacket having, distributed thereover at intervals, a plurality of localised indentations at which the jacket engages the wall of the vessel, each said indentation being entirely encircled by a respective zone over which the jacket is out of contact with, and spaced from the wall of the vessel.

According to the present invention there is provided temperature regulating, heating or cooling means, in the form of a plate. panel or baffle comprising two spaced apart walls defining therebetween a chamber between said walls, an inlet to and an outlet from said chamber being provided, a separately formed flow guiding member being disposed within said chamber, between said two spaced apart walls, for guiding the flow of fluid in the course of its passage through the chamber from the inlet to the outlet, said walls being of sheet metal and at least one of the walls having, distributed thereover at intervals, a plurality of localised indentations at which the last-mentioned wall engages the other said wall, each said indentation being entirely encircled by a respective zone over which said walls are out of contact with, and spaced from one another.

Embodiments of the invention are described below with reference to the accompanying drawings in which: Figure I is a schematic perspective view of a jacketed vessel which is the subject of our co-pending Application No. 24191/78, not embodying the present invention, but by Serial No. 1603361 reference to which embodiments of the present invention are explained below, Figure 2 is a side elevation view of part of the vessel of Figure 1, Figure 3 is a view in section along the line A-A in Figure 2, and Figure 4 is a view in vertical section of part of the side of the vessel of Figures I to 3.

The vessel 10 shown in Figure I has the general construction described and claimed in our co-pending Application No. 24996/76 (1, 582,836) the vessel being in the form of a tub of sheet metal, for example stainless steel, with a cylindrical side wall 12 which, over the major portion of its height, is surrounded by a sheet metal jacket 20 comprising a wall the major portion of which lies in a cylindrical surface coaxial with the wall 12 and spaced radially outwardly therefrom. At its upper and lower edges the wall of the jacket extends radially inwardly to engage the wall 12 and is welded thereto or is otherwise sealingly connected with the wall 12.

The jacket is indented at intervals to engage the wall 12 of the vessel and is welded to the wall of the vessel in the region of these indentations, the indentations being indicated at 22, As will be apparent from the drawings, and as described in our co-pending Applica- tion No. 24996/76, the indentations 22 are localised, being substantially circular in elevation as viewed in Figures I and'and each of the indentations 22 is entirely encircled by a respective zone over which the wall 20 is spaced from the wall of the vessel 10.

Disposed within the chamber defined between the wall 12 and the jacket 20 is a flow guiding member, indicated by the broken line 24 in the form of a metal strip, bar, tube or the like extending around the wall 12 after the fashion of a coil from the upper edge of the jacket to the lower edge thereof.

The flow guiding member 24 thus defines within the jacket, together with the wall 12 and the jacket an extended passage or rectangular section which extends in the fashion of a coil from the top of the jacket to the bottom.

At the top of the jacket is provided an inlet 30 which communicates with the coil like passage within the jacket adjacent the end of the uppermost turn and a similar outlet 32 extends from the jacket at the bottom thereof and communicates with the coil like passage adjacent the end of the lowermost turn.

It will be appreciated that the principles underlying the vessels described in the present application with reference to the drawings and in our co-pending application No.

24996/76 Serial No. 1582836, i. e. that of defining a chamber for heating or cooling fluid between a first wall and a second wall, of metal plate or sheet, secured to the first wall but spaced therefrom over most of its area, but indented at intervals to engage the first wall, and that of providing, within such a chamber, a flow buiding member for guiding the flow of fluid in the course of its passage through the chamber from the inlet to the outlet, are of more general application than to vessels of the kind specified, and that these principles need not necessarily be used in combination.

Thus, in general, any suitable wall of any member or structure to be heated or cooled may have an indented panel applied thereto in the same general manner as described with reference to the vessel of Figures I to 4 or the vessel disclosed in our co-pending Application No. 24996/76 (1, D8'836), whether or not the member or structure is a round vessel and the indented member is in the form of a jacket extending wholly around the vessel and defining a flow passage encircling the vessel several times, or whether, for example the member is a flat or curved plate, or a planar rectangular wall of a metal structure, in which case the indented member may, for example, be in the. form of rectangular indented panel sealingly secured around its edges, e. g. by welding, to the respective plate or wall.

Thus, it is possible to provide a variety of temperature regulating, heating or cooling means in the form of a plate. panel or baffle having, in effect, the form of an unrolled version of the jacketed wall of the vessel shown in Figures I to 4, such a plate, panel or baffle having, as viewed fragmentarily in elevation and in section the appearance shown in Figures 2, 3 and 4, and having the features shown therein.

Panels. plates or baffles having this form are referred to below as being"indented jacketed panels." Furthermore, whilst in the vessel of Figure I and that disclosed in our Application No.

24996/76 (1, 582, 836) the flow guiding member and the flow passage defined thereby extend in the form of a helix around the vessel, this is not practicable in the case of a flat or substantially flat panel. In the latter case the flow guiding member and the flow passage defined may take the form of a spiral in the plane of the panel or alternatively the flow guiding member, or a plurality of flow guiding members may be arranged to define a generally serpentine or zig-zag shaped flow passage from the inlet to the outlet through the chamber defined between the indented panel and the wall to which it is secured.

The provision of a flow guiding member or members, and the facility afforded thereby, of selecting substantially any predetermined flow path through the chamber, makes it possible for the inlet and the outlet to be disposed adjacent to each other, if desired.

Thus, such indented jacketed panels may have internal flow guiding members so arranged that the inlets and outlets are adjacent each other at the tops of the panels.

Steam heated indented jacketed heating pan- els so devised, in the form of baffles can be dropped into the top of a processing vessel to be immersed in the contents thereof, with both steam and condensate outlets of the panels at the top thereof. The internal flow guiding members in such indented jacketed panels will prevent"short circuiting"of the heating or cooling fluids directly from inlet to outlet.

Heating platens, in the form of such indented jacketed panels, and which are flat and planar on the top and indented underneath, may be used horizontally, for example in belt dryers operating in atmospheric conditions or under vacuum.

As another example, such indented jacket ing may be provided on the underside of trolleys, for example of stainless steel, in vacuum tray dryers, or on the underside of the trays themselves, so that the bottoms of such trolleys or trays are formed as such indented jacketed panels.

Furthermore, the vacuum chambers of such dryers, which have, up till now, been in the form of long heavy stainless steel boxes fitted externally with serpentine mild steel steam coils, the heat transfer characteristics of which are very poor, may instead have their upper and/or lower and/or side walls formed as indented jacketed panels in the manner described.

It has been found that the spacing between the walls of an indented jacketed panel of the form discussed, when used for heating by steam need often be no greater than whereas in conventional arrangements using plain jackets it has been customary to provide large steam voids, usually not less than I"and in some cases up to 2"wide. However, with arrangements having such large steam voids, when, for example a vessel is to be kept at a required temperature by the supply of steam to these voids, there is, during heating up, a lag between termination of the supply of steam and termination of the increase in temperature, so that the vessel and its contents may overshoot the desired temperature by several degrees due to the residual latent heat of the steam in the large voids. This problem can be much reduced by the use of indented jacketed panels of the kind thereinbefore described.

Claims (10)

1. As noted above, the vessel shown in the accompanying drawings is also described in, and is the subject of claims in, our copending Application No. 24191/78. Serial No. 1603361.

   WHAT WE CLAIM IS : 1. Temperature regulating, heating or cooling means, in the form of a plate, panel or baffle comprising two spaced apart walls defining therebetween a chamber between said walls, an inlet to and an outlet from said chamber being provided, a separately formed flow guiding member being disposed within said chamber, between said two spaced apart walls, for guiding the flow of fluid in the course of its passage through the chamber from the inlet to the outlet, said walls being of sheet metal and at least one of the walls having, distributed thereover at intervals, a plurality of localised indentations at which the last-mentiond wall engages the other said wall, each said indentation being entirely encircled by a respective zone over which said walls are out of contact with, and spaced from one another.
2. 2. Temperature regulating, heating or cooling means according to claim I wherein said inlet and outlet are adjacent one another.
3. 3. Temperature regulating, heating or cooling means according to claim I or claim 2 which is in the form of a baffle adapted to be immersed in a vessel for heating, cooling or regulating the temperature of a liquid in such a vessel.
4. 4. Temperature regulating, heating or cooling means according to claim I or claim 2 in the form of a platen, one of said walls being flat and the other having said indentations.
5. 5. A belt dryer incorporating a platen according to claim 4 in a horizontal position.
6. 6. A trolley for a vacuum tray dryer having a bottom formed as a platen in accordance with claim I or claim 2, the underside of said tray bottom being formed with such indentations.
7. 7. Temperature regulating, heating or cooling means according to claim I or claim 2 in the form of a tray for a vacuum tray dryer, the underside of said tray being formed with such indentations.
8. 8. A vacuum tray dryer comprising a vacuum chamber at least partly defined by or provided with a panel constituting temperature regulating, heating or cooling means according to claim I or claim 2.
9. 9. A dryer according to claim 8 wherein an outer wall of the vacuum chamber is provided by a said wall formed with such indentations.
10. 10. A temperature regulating, heating or cooling means according to any preceding claim wherein the spacing between the walls between which the chamber for fluid is defined is less than half an inch.