METHOD OF MANUFACTURING A METAL LINING AND A METAL LINING MANUFACTURED ACCORDING TO THE METHOD

Abstract: Method of manufacturing a metal lining for a plate heat exchanger and a metal lining manufactured according to this method. The method comprises plastic machining of a smooth plate (10) such that a cylindrical part (30) and at least one edge flange (31) is formed. The metal lining comprises at least one cylindrical part and at least one but preferably two flanges (41, 44; 51, 52).

Description: Method of manufacturing a metal lining and a metal lining manufactured according to the method This invention relates to a method of manufacturing a metal lining for use in plate heat exchangers and a metal lining manufactured according to the method. A plate heat exchanger comprises a number of heat exchanger plates which are fastened between a frame plate and a pressure plate. In this connection it shall be a good contact between the frame plate and/or the pressure plate and the closest heat exchanger plate. In the frame plate and/or the pressure plate there are made inlet holes and outlet holes for the heat exchanging media. These media can be corrosive and, therefore, corrode non-alloy steel. There is, however, a wish to manufacture the frame plate and /or the pressure plate of a material which is as cheap as possible and which as a rule does not resist corrosive media. This problem has been solved by a lining, for instance of metal, which has been inserted into the inlet ports and the outlet ports of the frame plate and/or the pressure plate. The lining is to re¬ sist the corrosive medium that goes through the inlet ports and the outlet ports. When using metal linings the basic material has previously been a cylinder on which has been fastened a flange by welding on each side of the hole of the frame plate and/or the pressure plate. In order to be able to weld the flanges on the cylinder the thickness of the material ought to be at least 3 mm. This has led to that such a metal lining has not been able to be applied directly to the side surface of an unmachined frame plate, because it would have implied that the distance between the frame plate or the pressure plate and the closest heat exchanger plate has become unacceptably large. Of this reason each frame plate and/or pres- OMPI sure plate that has been provided with a metal lining has had to be machined such that a recess for the flanges of the lining has been made at the connection holes on each side of the plate. Such a machining is both expensive and time-consuming and requires an expensive machine equipment. Moreover, the welding of the flanges onto the cylinder, which working moment per se also is both time-consuming and expensive, involves that unacceptable cracks can be introduced into the weld having the consequence that the lining has to be rejected or that a new weld has to be done. Thus, control measures are an essential feature in connection with the welding procedure, which still more raises the price of the metal linings. These disadvantages taken together have led to that conventional metal linings have become too expensive to manufacture and use. This invention Is intended to make the manufacture and use of metal linings cheaper and accordingly make an increased use of these ones possible. Two preferred embodiments and a preferred manufacturing method according to the Invention shall be described more closely in con¬ nection with the enclosed drawing, In which Fig. 1 discloses the basic material when manufacturing the metal lining, Fig. 2 discloses the situation after a first working moment, Fig. 3 discloses the situation after a second working moment, Fig. 4 discloses the lining inserted Into a frame plate with the second flange shown with broken lines, and Fig. 5 discloses an alternative embodiment of a metal lining in¬ serted into a frame plate. When manufacturing a metal lining the basic material is a smooth, thin metal plate of a suitable quality, preferably in the form of a round, the thickness of which is less than 3 mm and preferably 1 mm or less than that. This plate is plastically machined, pre¬ ferably by means of deep drawing, pressure rolling and/or press¬ ing, such that a cylindrical pot 20 with edge flange 21 (see Fig. 2) is formed. From this pot the bottom is then removed, whereby an open cylinder 30 with an edge flange 31 is formed. Before the cylinder is inserted into the frame plate and/or the pressure plate a heat treatment is made if it is deemed to be necessary. Then the cylinder is placed in the frame plate and/or the pressure plate 40 with its edge flange 41 towards one side 42 of the plate. In order that the cylinder shall be able to act as an effective lining a flange ought to be arranged on the cylinder also on the other side 43 of the plate 40. This is done by flang- ing out a part of the cylinder, whereby a flange 44 is formed on the other side 43 of the plate. The flanging is preferably made by pressure rolling and/or pressing. In the described method the basic material is an unholed plate in the form of a round, which has been formed to a cylindrical pot from which the bottom has been removed. It is, however, also pos¬ sible to start with a holed plate, for instance a round provided with a hole. In this case an open cylinder with edge flange is directly formed when machining the plate. The described metal lining is provided with flanges that are not fastened by means of welding but have been machined out of the basic material. Due to that fact the lining can be made of a very thin plate which per se makes the manufacture of the lining ,chea- per. The most important advantage with the thin lining, however, is that the side walls of the frame plate and the pressure plate do not need to be machined for the flanges of the lining, which as has been mentioned previously is a very expensive operation. These flanges become so thin that they can be put on the outside of the side walls of the frame plate and/or the pressure plate. The metal lining is preferably designed such that the cylinder section in a plane essentially parallel with the flange/flanges is circular or elliptic. In Fig. 5 there is disclosed an alternative embodiment of the in¬ vention. In this case the metal lining comprises two parts 51/52 fastened to each other, preferably by means of welding. In this connection each part comprises a cylindrical part with an edge flange resting against respective side of the frame plate 50. The parts 51, 52 are preferably manufactured by means of deep drawing, pressure rolling and/or pressing of a smooth plate in a similar way as disclosed in Figs. 1-3. The advantage with this embodiment Is that for given dimensions on the parts 51, 52 the metal lining by moving the parts 51, 52 to or from each other previous to the welding procedure can be used in frame plates and/or pressure plates of different sizes. -fjUREA

Claims: AMENDED CLAIMS [received by the International Bureau on 04 November 1983 (04.11.83); original claims 1 to 10 replaced by amended claims 1 to 10] 1. Metal lining for lining of inlet ports and/or outlet ports of a frame plate and/or a pressure plate of a plate heat exchanger and comprising at least one cylindrical part and at least one but preferably two flanges, each of which intended to rest against the side wall of the frame plate and/or pressure plate, c h a r a c ¬ t e r i z e d i n that at least that one of the flanges (4l, 44; 51, 52) that is intended to rest against a heat exchanger plate is formed by plastic machining of the basic material (10). 2. Metal lining according to claim 1, c h a r a c t e r i z e d i n that it comprises two parts (51, 52) welded to each other, and that each part (51, 52) comprises a cylindrical part with an edge flange belonging to it. 3. Metal lining according to claim 1 or 2, c h a r a c t e r ¬ i z e d i n that at least that one of the flanges (41, 44; 51, 52) that is intended to rest against a heat exchanger plate is made of such a thin-walled material that it can be put against the unmachined side wall of the frame plate and/or the pressure plate (40; 50). 4. Metal lining according to anyone of the preceding claims, c h a r a c t e r i z e d i n that the basic material (10) has a thickness that is less than 3 mm and preferably 1 mm or less than that. 5. Metal lining according to anyone of the preceding clams, c h a r a c t e r i z e d i n that a section of the cylinder in a plane essentially parallel with the flange/flanges (31; 41, 44; 51, 52) is circular. 6. Metal lining according to anyone of the claims 1-4, c h a ¬ r a c t e r i z e d i n that a section of the cylinder in a plane essentially parallel with the flange/flanges (31; 41, 44; 51, 52) is elliptic. 7. Method of manufacturing a metal lining according to anyone of the claims 1-6, c h a r a c t e r i z e d i n that a metal¬ lic plate (10) is plastically machined such that a cylinder (30) with at least one edge flange (31) is formed. 8. Method according to claim 7, the metal plate comprising a smooth-formed, unholed round, c h a r a c t e r i z e d i n that the round (10) Is machined by means of deep drawing, pressure rolling and/or pressing such that a cylindrical pot (20) with edge flange (21) is formed, whereafter the bottom is removed from the pot. . Method according to claim 7, the metal plate comprising a smooth-formed, holed round, c h a r a c t e r i z e d i n that the round (10) is machined by means of deep drawing, pressure rolling and/or pressing such that an open cylinder (30) with an edge flange (31) is formed. 10. Method according to anyone of the claims 7-9, the lining comprising two flanges, one on each side of the cylindrical part, c h a r a c t e r i z e d i n that the second flange (44) is formed by flanging a part of the cylindrical part (30), the flang¬ ing being made by pressure rolling and/or pressing.

Inventors: ANDERSSON JARL, EDSOE LENNART, JOENSSON NILS-AOKE, RISSLER PER, ANDERSSON, JARL, EDSOE, LENNART, JOENSSON, NILS-AOKE, RISSLER, PER
Applicants: ALFA LAVAL THERMAL, ALFA-LAVAL THERMAL AB
Application year: 1983
Main classification: F28F9
IPC codes: B21D53, F28D9, F28F3, F28F9, F28F19