WO2022228873A1 - Metal bellows and method for the production thereof - Google Patents
Metal bellows and method for the production thereof Download PDFInfo
- Publication number
- WO2022228873A1 WO2022228873A1 PCT/EP2022/059566 EP2022059566W WO2022228873A1 WO 2022228873 A1 WO2022228873 A1 WO 2022228873A1 EP 2022059566 W EP2022059566 W EP 2022059566W WO 2022228873 A1 WO2022228873 A1 WO 2022228873A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- metal bellows
- flanks
- die
- wall
- ring
- Prior art date
Links
- 239000002184 metal Substances 0.000 title claims abstract description 103
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 103
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 12
- 238000000034 method Methods 0.000 title claims description 22
- 230000007704 transition Effects 0.000 claims abstract description 10
- 230000006835 compression Effects 0.000 claims description 25
- 238000007906 compression Methods 0.000 claims description 25
- 239000011159 matrix material Substances 0.000 claims description 7
- 239000010410 layer Substances 0.000 claims description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 4
- 238000000465 moulding Methods 0.000 claims description 4
- 239000002356 single layer Substances 0.000 claims description 4
- 229910045601 alloy Inorganic materials 0.000 claims description 2
- 239000000956 alloy Substances 0.000 claims description 2
- 229910000963 austenitic stainless steel Inorganic materials 0.000 claims description 2
- 229910052759 nickel Inorganic materials 0.000 claims description 2
- 239000012528 membrane Substances 0.000 description 13
- 239000012530 fluid Substances 0.000 description 6
- 239000000463 material Substances 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J3/00—Diaphragms; Bellows; Bellows pistons
- F16J3/04—Bellows
- F16J3/047—Metallic bellows
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D15/00—Corrugating tubes
- B21D15/04—Corrugating tubes transversely, e.g. helically
- B21D15/06—Corrugating tubes transversely, e.g. helically annularly
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D15/00—Corrugating tubes
- B21D15/04—Corrugating tubes transversely, e.g. helically
- B21D15/10—Corrugating tubes transversely, e.g. helically by applying fluid pressure
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
Definitions
- the invention relates to a metal bellows with a tubular wall, produced from a thin-walled pipe section or from several thin-walled metal pipe sections joined together, according to the preamble of claim 1 and a method for producing such a metal bellows according to the preamble of claim 10.
- a metal bellows of the present type has a number of annular corrugations molded into the tubular wall. These corrugations each include an outer rim running in the circumferential direction of the wall and two corrugated flanks adjoining this. The flanks of a wave, together with the associated outer brim, describe the interior of a wave. The flanks of two adjacent waves each enclose an inner flange running in the circumferential direction of the wall.
- metal bellows have been known for a long time and are used in a wide variety of applications. Due to the elastic deformability of the ring-shaped corrugations, metal bellows can move both axially and angularly and laterally, but are still fluid-tight and temperature-resistant at all times, and if the appropriate material is selected, they are also corrosion-resistant.
- the corrugations of ring-corrugated metal bellows are symmetrically shaped in their profile; in an axial section they roughly describe a sine wave or, most commonly, a compressed sine wave, which, viewed from inner rim to inner rim, leads to a W-profile of the individual waves.
- a number of annular corrugations are molded into a single-layer or multi-layer, cylindrical or flattened, thin-walled tube, usually by hydro-forming the wall at internal high pressure.
- a section of pipe divided by external and internal tools is deformed under pressure by introducing a liquid into its interior.
- the wall of the pipe section bulges and forms a pre-wave.
- two matrix ring tools are attached to the wall of the pipe section from the outside, which prevent the pipe from being radially expanded by the internal pressure at the points where the inner rims of the corrugations are to form.
- the pre-wave is thus formed into an intermediate space between the two ring dies, in that the wall bulges in a nus-shaped manner there.
- the die ring tools are moved towards one another in order to form the desired wave from the pre-wave.
- metal bellows of the present type are composed of individual annular disks with a truncated cone shape in longitudinal section, in that two annular disks are welded together at their radially inner edges in the opposite direction, in order to form a membrane pair, which are then attached to their outer edges are welded to other pairs of membranes, usually with a flat seam at the front.
- This design of a metal bellows allows in particular a movement stroke up to the block and thus a FITS short overall length.
- a membrane bellows which is composed of individual membrane discs, has special properties compared to a metal bellows with moulded, mostly omega-shaped corrugations, in particular a lower axial one Stiffness and a very favorable ratio of stroke to free length of the metal bellows, ie the membrane bellows can be manufactured with particularly short overall lengths. Due to its special properties, a diaphragm bellows is mostly used as a volume compensation element or for load cells.
- the invention is therefore based on the object of proposing a metal bellows of the type mentioned and a method for its production, with which the advantages of a conventional diaphragm bellows, as described above, are combined with the advantages of a metal bellows produced by hydroforming.
- the waveform according to the invention can be referred to as a C-wave, since the curvatures of both wave flanks have the same orientation and are continuously curved with the same orientation until they merge tangentially into the outer and inner rims of the metal bellows.
- This new waveform according to the invention can, in contrast to the conventional sine or omega wave, very easily be compressed to the point of contact with the brim or even beyond, so that a metal bellows according to the invention with C-waves has the advantageous properties of a conventional membrane bellows.
- the metal bellows according to the invention with C-waves can be produced by forming the tube section of the tubular wall, and it is also preferably produced in this way, in particular by hydraulic internal high-pressure forming.
- the welded connections between the individual membrane disks that are necessary for the production of a conventional membrane bellows can be omitted, so that ultimately the specific advantages of a membrane bellows, which the metal bellows with C-waves according to the invention also has, are not due to higher production costs and disadvantageous weld seams in stressed areas of the material must be purchased.
- the present invention combines the advantages of two conventional types of metal bellows.
- the wave flanks of the metal bellows according to the invention are expediently curved in such a way that one of the two wave flanks of a wave has an im Substantially convex and the other of the two wave flanks have a substantially concave profile, each seen in a sectional plane including the axis of the metal bellows and to be understood in relation to the shaft interior.
- essentially all corrugation flanks of the metal bellows are provided with a curvature oriented in the same way, so that all corrugations of a metal bellows according to the invention, optionally except for pre-corrugations arranged at the ends, are formed in an identical shape.
- the C-corrugations of the metal bellows according to the invention are shaped in such a way that the curvatures of their corrugation flanks have a substantially constant radius of curvature.
- the ratio of the outer diameter of the bellows to the inner diameter of the bellows is as large as possible.
- a Da/Di ratio of 1.3 to 1.5 should be aimed for, which implements the properties of a diaphragm bellows, in particular a high specific expansion absorption and thus a particularly short overall length or a particularly good suitability as a volume compensation body, in a particularly pronounced manner.
- the radial extent of the wave flanks i.e.
- the transition to the outer rim to the transition to the inner rim expediently has a ratio of at least 3: 1, better still at least 4: 1 and more preferably at least 5: 1 to the radial extent of the outer rim and/or the inside flaps open.
- the C-waves viewed in the radial direction, are very elongated.
- the metal bellows according to the invention can also be carried out Reshaping a multi-layer cylindrical pipe section are produced; thus, the metal bellows according to the invention can be provided with a multi-layer wall, although it can have the advantageous properties of a conventional membrane bellows. In this respect, too, the advantages of two different conventional designs are combined according to the invention.
- the wall of the metal bellows according to the invention is preferably made of austenitic stainless steel or a nickel-based alloy.
- the method according to the invention for producing a metal bellows with a tubular wall made of at least one metal sheet comprises, as is known per se, the molding of a number of ring-shaped corrugations into a single-layer or multi-layer cylindrical tube, the ring-shaped corrugations each having an outer rim running in the circumferential direction of the wall and two corrugated flanks adjoining these, and wherein each corrugation is formed by hydraulic internal high-pressure forming of the wall all around into a gap between two die-ring tools, which surround the cylindrical tube and prevent the tube from where the inner rims are to form, is radially expanded. It is therefore a conventional hydraulic internal high-pressure forming.
- both matrix ring tools are provided with contours for molding each shaft, to which the shaft to be shaped rests during forming, the contour of one of the two matrix ring tools being essentially convex and the contour of the other of the two die ring tools is essentially concave.
- the C-corrugation according to the invention described above, is formed, in which both corrugation flanks from the transition to the outer rim to the transition to the inner rim are provided with identically oriented curvatures, in particular with a substantially constant radius of curvature.
- the method according to the invention can be implemented in such a way that the corrugations are individually formed into the tubular wall by pushing the initially cylindrical tube into two die ring tools designed as a compression plate and a die plate and inserting a pressure tube into the cylindrical tube. to apply hydraulic pressure to a section of tubing extending from one die ring die to the other.
- the pipe section bulges out and is formed into the space between the die ring tools.
- the die ring tools are moved towards one another.
- the wall of the formed pipe section rests against the contours of the die ring tools and adopts their contours, so that the C-waves according to the invention are formed.
- waves of the metal bellows are simultaneously formed into the tubular wall by the initially cylindrical tube being inserted into a die with a number of die-ring tools, two of which serve as front and rear upset disks and the rest are designed as die plates.
- a front pressure pipe section is introduced into the cylindrical tube at the level of the front compression disc, while a rear pressure pipe section is introduced at the level of the rear compression disc in order to apply hydraulic pressure to a section of pipe located between the two pressure pipe sections. If the pipe section sections with the help of the two pressure pipe used in this is subjected to hydraulic pressure, the wall is formed in the spaces between the die-ring tools.
- the die ring tools are moved towards one another with increasing deformation of the tube section until the wall of the tube section rests against the contours of the die ring tools and is formed into a metal bellows with several corrugations.
- the wave flanks take on the contours of the die ring tools, as a result of which the C waves according to the invention are formed.
- the C-shafts produced according to the invention in hydraulic internal high-pressure forming with matrix ring tools with convex and concave contours have a relatively large opening angle between the two shaft flanks; the radii of curvature of the outer rims (and the inner rims) are generally still too large for optimal mobility of the metal bellows.
- an upsetting tool is preferably used, which essentially consists of a front upsetting ring and a rear upsetting ring, which are placed in front of the frontmost and behind the rearmost shaft of the metal bellows and are moved toward one another.
- one of the two compression rings has a convex and the other of the two compression rings has a concave contact surface for the corrugations of the metal bellows, so as not to impair the C-corrugations according to the invention during compression.
- FIG. 1 shows a schematic sectional illustration of a metal bellows designed according to the invention
- FIGS. 2a to 2e show schematic sectional views of different procedural steps when forming a C-shaft by means of hydraulic forming tools
- FIGS. 4a and 4b show schematic sectional representations of two process steps when upsetting the metal bellows produced by hydraulic forming.
- FIG. 1 is a schematic sectional representation of an exemplary embodiment of a metal bellows 23 designed according to the invention with the C-waves according to the invention.
- the section is made so that it encloses the central axis of the metal bellows 23 , which is cylindrical in shape.
- the metal bellows has a tubular wall 1 , in this case consisting of a high-grade steel sheet metal, from which a cylindrical tube was produced, which was finally formed into the present metal bellows 23 by hydraulic internal high-pressure forming of the wall 1 .
- the tubular wall 1 has a number of ring-shaped corrugations 2, each of which comprises an outer rim 3 running in the circumferential direction of the wall 1 and two corrugated flanks 4a, 4b adjoining this.
- the two wave flanks 4a, 4b and the outer brim 3 circumscribe a shaft interior 5, and the waves flank 4a, 4b' of two adjacent shafts 2, 2' each include a circumferential direction in order of the wall running inner brim 6 between them.
- the wavy flanks 4a, 4b of the metal bellows 23 shown each have a substantially constant radius of curvature, resulting in the characteristic C-wave that gives the metal bellows 23 at least largely the advantageous properties of a conventional membrane bellows.
- a radial expansion 8 of the corrugated flanks 4a, 4b has a ratio of approximately 6:1 to a radial expansion 9 of the outer flanges 3 and to a radial expansion 10 of the inner flanges 6 If the ratio of the outside diameter of the bellows to the inside diameter of the bellows Da/Di is greater than 1.3, the metal bellows has a particularly high degree of axial mobility and in this respect has very good properties for use as a volume compensation element.
- metal bellows according to the invention can also be advantageous, for example as a decoupling element in a pipeline subjected to vibration; because the asymmetric configuration of the C-waves 2 according to the invention can result in advantageous effects on the natural frequencies of the metal bellows 23 and thus on any resonances.
- FIGS. 2a to 2e are schematic sectional views of a forming tool in which a C-shaft according to the invention is produced step by step by hydraulic internal high-pressure forming. It is a mold set consisting of a compression disc 11 and a die disc 12 as well as a pressure pipe 13 with a central through hole 14 and an outlet hole 15 for a hydraulic fluid 16.
- a cylindrical tube 17, from which the metal bellows is to be made, is pushed onto the pressure tube 13, while the upsetting disk 11 and the die disk 12 are opened radially.
- a pressure chamber into which the hydraulic fluid 16 is introduced is formed between two O-ring seals 18 which delimit a pipe section 19 of the cylindrical pipe 17 between them, the cylindrical pipe 17 and the pressure pipe 13 .
- the forming tool is closed beforehand by lowering the upsetting disk 11 and the die disk 12 onto the cylindrical tube 17.
- FIG. This ensures, among other things, that the cylindrical tube 17 is not lifted off the O-ring seals 18 even when the hydraulic fluid 16 is introduced.
- the bulge which becomes a pre-wave, is compressed, so that the shaft 2 rests with its shaft flanks 4a, 4b laterally against the contours 21, 22 of the compression disk 11 and the die disk 12.
- the contour 21 of the upsetting disk 11 is concave in shape
- the contour 22 of the die disk 12 is convex in shape (which of course can also be the case vice versa). This then results in the concave shape of the wave flank 4a and the convex shape of the wave flank 4b.
- FIG. 2e After the forming tool has been opened, as shown in FIG. 2e, the cylindrical tube 17 is axially displaced on the pressure tube 13 in order to form a second wave by repeating the process. The process is repeated until the desired number of shafts 2 has been produced.
- Figures 3a to 3c show an alternative procedure for introducing the C-waves 2 into a cylindrical tube 17: All waves 2 are simultaneously introduced into the cylindrical tube 17 by means of hydraulic internal high-pressure forming:
- FIG. 3a shows, a front pressure pipe section 24 and a rear pressure pipe section 25 are pushed into the two ends of the cylindrical pipe 17, which seal the cylindrical pipe 17 to the outside by means of O-ring seals 18.
- the pressure chamber 26 formed in this way remains accessible due to through bores 14 and can thus be subjected to hydraulic pressure.
- a front compression disc 27 with a convex contour 28 and a rear compression disc 29 with a concave contour 30 are attached.
- a rear upsetting disk 29 and the front upsetting disk 27 there are several die disks 12, 12', 12" at regular intervals, which are also attached to the cylindrical tube with their radially inner tips, which ultimately form the inner rims 6 of the shafts 2 are.
- FIG. 3b shows how the pressure chamber 26 is pressurized by introducing hydraulic fluid 16.
- the cylindrical tube 17 bulges radially outwards, with the radially inner tips of the die plates 12, 12', 12'' preventing bulging at this point.
- the wall of the cylindrical tube 17 is simultaneously formed into the space 20, 20', 20" between the die plates 12, 12', 12" and compression plates 27, 28, whereby, as with the single-wave formation from the example of FIGS. 2a to 2e, the gaps 20, 20', 20'' are successively reduced by moving the matrix ring tools 12, 12', 12'', 27, 29 together.
- FIG. 3b The pre-waves that are already partially formed in FIG. 3b are, as FIG. 3c shows, caused by the die ring tools being moved completely together Maintaining the hydraulic pressure in the pressure chamber 26, formed in the contours 22, 28, 30 of the die ring tools, resulting in the inventions to the invention C-wave arise.
- the forming process is now complete, and the formerly cylindrical tube 17 that has become the metal bellows 23 with annular corrugations 2 can be removed.
- FIGS. 4a and 4b show an advantageous post-treatment of the metal bellows 23, which has actually already been completely formed, with C-corrugations 2, again in a schematic sectional view.
- the metal bellows 23 is first pushed onto a support cylinder 31 in order to stabilize it against lateral and angular movements. Then, in front of which compression ring 32 with a convex contact surface 33 is attached to one end of the metal bellows at its foremost shaft 2. At the same time, a rear compression ring 34 with a concave contact surface 35 is attached to the other end of the metal bellows, at its rearmost shaft 2 . This initial state is shown in FIG. 4a.
- the two compression rings 32, 34 are moved together and the metal bellows together with its corrugations 2, 2', 2'' are compressed, preferably until the outer and inner flanges 3, 6 are in contact with one another. if necessary even beyond that, so that the radii of the brims 3, 6 are reduced to a desired level.
- the support cylinder 31 prevents the metal bellows from buckling.
- the desired radii of the outer rims 3 and the inner rims 6 can be achieved by upsetting. The result is a metal bellows as shown in FIG. Reference list:
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Diaphragms And Bellows (AREA)
Abstract
Description
Claims
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020237040293A KR20240001184A (en) | 2021-04-27 | 2022-04-11 | Metal bellows and its manufacturing method |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE102021110746.6 | 2021-04-27 | ||
DE102021110746.6A DE102021110746A1 (en) | 2021-04-27 | 2021-04-27 | Metal bellows and method of making one |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2022228873A1 true WO2022228873A1 (en) | 2022-11-03 |
Family
ID=81595831
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2022/059566 WO2022228873A1 (en) | 2021-04-27 | 2022-04-11 | Metal bellows and method for the production thereof |
Country Status (3)
Country | Link |
---|---|
KR (1) | KR20240001184A (en) |
DE (1) | DE102021110746A1 (en) |
WO (1) | WO2022228873A1 (en) |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3469502A (en) * | 1967-02-09 | 1969-09-30 | Robert I Gardner | Bellows |
US3782156A (en) * | 1971-01-25 | 1974-01-01 | Master Products Mfg Co | Stacked bellows and apparatus and method for manufacturing the same |
US4364252A (en) * | 1980-04-12 | 1982-12-21 | Osaka Rasenkan Kogyo Kabushiki Kaisha | Method for the manufacture of diaphragm bellows |
US5261319A (en) * | 1991-01-17 | 1993-11-16 | Eg Et G | Bellows with curved waves having points of contact |
JPH11226658A (en) * | 1998-02-19 | 1999-08-24 | Nhk Spring Co Ltd | Diaphragm type formed bellows and its manufacture |
EP1166912A2 (en) * | 2000-06-16 | 2002-01-02 | Nhk Spring Co., Ltd. | Apparatus for and method of manufacturing metallic bellows |
EP3342497A1 (en) * | 2016-12-30 | 2018-07-04 | SJM Co. Ltd. | Method for manufacturing a diaphragm bellows member |
-
2021
- 2021-04-27 DE DE102021110746.6A patent/DE102021110746A1/en active Pending
-
2022
- 2022-04-11 WO PCT/EP2022/059566 patent/WO2022228873A1/en active Application Filing
- 2022-04-11 KR KR1020237040293A patent/KR20240001184A/en unknown
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3469502A (en) * | 1967-02-09 | 1969-09-30 | Robert I Gardner | Bellows |
US3782156A (en) * | 1971-01-25 | 1974-01-01 | Master Products Mfg Co | Stacked bellows and apparatus and method for manufacturing the same |
US4364252A (en) * | 1980-04-12 | 1982-12-21 | Osaka Rasenkan Kogyo Kabushiki Kaisha | Method for the manufacture of diaphragm bellows |
US5261319A (en) * | 1991-01-17 | 1993-11-16 | Eg Et G | Bellows with curved waves having points of contact |
JPH11226658A (en) * | 1998-02-19 | 1999-08-24 | Nhk Spring Co Ltd | Diaphragm type formed bellows and its manufacture |
EP1166912A2 (en) * | 2000-06-16 | 2002-01-02 | Nhk Spring Co., Ltd. | Apparatus for and method of manufacturing metallic bellows |
EP3342497A1 (en) * | 2016-12-30 | 2018-07-04 | SJM Co. Ltd. | Method for manufacturing a diaphragm bellows member |
Also Published As
Publication number | Publication date |
---|---|
KR20240001184A (en) | 2024-01-03 |
DE102021110746A1 (en) | 2022-10-27 |
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