EP0532598A1 - Method of manufacturing tubes. - Google Patents
Method of manufacturing tubes.Info
- Publication number
- EP0532598A1 EP0532598A1 EP91910864A EP91910864A EP0532598A1 EP 0532598 A1 EP0532598 A1 EP 0532598A1 EP 91910864 A EP91910864 A EP 91910864A EP 91910864 A EP91910864 A EP 91910864A EP 0532598 A1 EP0532598 A1 EP 0532598A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- extrusion
- forming material
- billet
- recesses
- tubular
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
- B22F5/10—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of articles with cavities or holes, not otherwise provided for in the preceding subgroups
- B22F5/106—Tube or ring forms
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C23/00—Extruding metal; Impact extrusion
- B21C23/02—Making uncoated products
- B21C23/04—Making uncoated products by direct extrusion
- B21C23/08—Making wire, bars, tubes
- B21C23/085—Making tubes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C23/00—Extruding metal; Impact extrusion
- B21C23/22—Making metal-coated products; Making products from two or more metals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C33/00—Feeding extrusion presses with metal to be extruded ; Loading the dummy block
- B21C33/004—Composite billet
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
- B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
- B22F5/10—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of articles with cavities or holes, not otherwise provided for in the preceding subgroups
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F1/00—Tubular elements; Assemblies of tubular elements
- F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F21/00—Constructions of heat-exchange apparatus characterised by the selection of particular materials
- F28F21/08—Constructions of heat-exchange apparatus characterised by the selection of particular materials of metal
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
- B22F2005/004—Article comprising helical form elements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
- B22F5/10—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of articles with cavities or holes, not otherwise provided for in the preceding subgroups
- B22F2005/103—Cavity made by removal of insert
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
- B22F2998/10—Processes characterised by the sequence of their steps
Definitions
- the invention relates to the manufacture of tubes, especially tubes having elevations or recesses. More specifically, the invention relates to the manufacture of tubes in which an extrusion billet, consisting of a tubular material and a forming material, is preformed using powder- metallurgical methods.
- the tubes are normally provided with elevations or recesses in the form of channels, grooves, fins, flanges or openigns by mechanical treatment and/or welding in a step following the extrusion.
- Certain types of elevations or recesses may also be achieved directly during the extrusion. This is true, for example, with grooves or fins which are substantially oriented in the direction of extrusion, that is, above all axially directed and slightly helical grooves or fins .
- the prior art does not provide for the possibility of extruding tubes with elevations or recesses which are substantially directed in the direction of extrusion.
- an extrusion billet consisting of at least two materials, tubular material and forming material
- a forming material is preformed by inserting a forming material into or applying a forming material onto the tubular material and jointly compacting the materials into an extrusion billet so that, during the extrusion, the desired elevations or recesses are formed in the tubular material.
- the forming material is removed.
- the method is especially applicable to the manufacture of corrosion- resistant tubes in which material with a low corrosion resistance may be inserted as forming material in a corrosion-resistant tubular material and be easily removed by pickling after extrusion.
- the extrusion billet with insertions of the forming material is preformed, according to one embodiment of the invention, by filling the powdered forming material into slots on a starting billet of the tubular material, which has been pro ⁇ vided with relevant slots, and compacting the powdered forming material and binding it to the starting billet by isostatic pressing, preferably hot-isostatic pressing.
- isostatic pressing preferably hot-isostatic pressing.
- the starting billet may be produced in conventional manner by mechanical treatment or by powder-metallurgical pressing, preferably isostatic pressing, or combinations thereof.
- the extrusion billet is manufactured directly from at least two powdered mate ⁇ rials, one constituting the forming material and the other the tubular material, by compacting the powdered materials into a compound body, with insertions of the forming material in a matrix of the tubular material.
- the materials may be placed adjacent to each other or be separated by a partition, for example in the form of a sheet.
- the billet is then compacted by means of conventional powder- metallurgical methods, preferably by hot-isostatic pressing.
- the extrusion billet with insertions After the extrusion billet with insertions has been formed, it is extruded in conventional manner, whereupon the inserted forming material is removed, preferably by pickling.
- extrusion billets manufactured according to the invention With extrusion billets manufactured according to the invention, the possibility is obtained of manufacturing tubes with elevations or recesses in the form of channels, grooves, fins, flanges or openings, regardless of the orientation thereof, without any subsequent mechanical treatment or welding of the extruded tubes being required.
- tubes containing elevations and recesses may be manufactured essentially without expensive mechanical after-treatment.
- the material yield is enhanced, which is valuable in the manufacture of high-alloy tubes or tubes of other expensive materials.
- Figure 1 illustrates feasible process steps in the manufacture of tubes according to the invention
- Figure 2 exemplifies a number of feasible forms of elevations and recesses.
- Figure 1 shows how, according to the invention, elevations and recesses in the form of channels, grooves, fins, flanges or openings, regardless of the orientation thereof, are achieved when manufacturing tubes by extrusion.
- a body is preformed (at 1) of at least two materials, a forming material being inserted into or applied to a tubular material.
- This body of tubular material with insertions/applications of a forming material is compacted (at 2) into an extrusion billet.
- the extrusion billet is extruded (at 3) in conventional manner into a tube, whereupon the forming material is removed (at 4) , preferably by pickling, thus obtaining a tube with the desired recesses or elevations.
- conventional measures are, of course, taken, for example to secure and check the quality of the produced tube or to obtain the desired material properties. For example, measures such as surface treatment, heat treatment, adjustment of dimensions and shapes by mechanical treatment may be taken both between the process steps described above and after these.
- the forming material is inserted into or applied to a preformed starting billet of tubular material, the powdered material being filled into recesses provided in the starting billet, or applied to even out elevations provided on the starting billet so that, after compaction at 2, an extrusion billet is obtained.
- the tubular material may be inserted into or applied to a preformed starting billet of tubular material.
- the insertion or application of tubular material or forming material takes place by placing the starting billet in a cylindrical capsule, whereupon the capsule and any recesses provided in the starting billet are filled with the powdered forming material .
- the capsule is evacuated and sealed essentially gas-tightly before the capsule, containing the starting billet and the powdered forming material or tubular material, is compacted at 2.
- the starting billet Before the starting billet is placed in the capsule, it has been preformed in an arbitrary manner, it then being provided with elevations or recesses, for example by conventional mechanical treatment but preferably by being preformed by powder-metallurgical pressing, suitably isostatic or semi-isostatic pressing.
- the preformed body with insertions/applications of forming material is then compacted at 2, preferably by hot-isostatic pressing, but also cold-isostatic or semi-isostatic pressing with sintering provides useful extrusion billets.
- the extrusion billet is then extruded at 3 into a tube, whereupon the forming material is removed at 4.
- At least two powder materials may be supplied to a mould and be directly formed, at 3, into a green body with inser ⁇ tions/applications of a forming material in a matrix of a tubular material.
- This green body is compacted at 2 in the manner described above, preferably by hot-isostatic press ⁇ ing, into an extrusion billet which is then extruded at 3. After the extrusion, the forming material is removed at .
- Figure 2 shows a number of possible extrusion billets in which a forming material 21 has been inserted into a matrix of a tubular material 22 in order to form, during the extrusion, the tubular material 22 with elevations and/or recesses in the form of channels, grooves, fins, flanges or openings .
- Tubes included in heat- or power-generating plants as well as in chemical reactors are required to effectively transfer heat between the media on the different sides of the tube walls .
- these tubes are often provided with grooves or fins. These fins or grooves are often oriented in a direction deviating from the axial direction, for example spirally oriented.
- the technique according to the invention is advantageously applied to the manufacture of these tubes, the tubular material normally consisting of a corrosion-resistant material which is shape- resistant to high temperatures, such as, for example, an alloyed steel containing 12 - 30% Cr, and the forming material of an ordinary low-alloy steel.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Geometry (AREA)
- Extrusion Of Metal (AREA)
- Powder Metallurgy (AREA)
Abstract
Pour la fabrication de tubes possédant des surépaisseurs ou des évidements, une billette d'extrusion est préformée (1) et compactée (2) par pressage isostatique puis extrudée (3) à travers un tube. La billette d'extrusion est constituée d'eau moins deux matériaux, un matériau de formage (21) et un matériau tubulaire (22). Le matériau de formage est appliqué sur ou inséré dans un corps préformé en matériau tubulaire ou inversement, avant que le corps ne soit compacté en billette d'extrusion. Selon un autre procédé, le matériau tubulaire et le matériau de formage sont introduits dans un moule à l'état de poudre et sont compactés ensemble pour former une billette d'extrusion. Durant l'extrusion, le matériau de formage provoque des surépaisseurs ou des évidements dans le matériau tubulaire. Après l'extrusion, on retire le matériau de formage (4), de préférence par décapage.For the manufacture of tubes having extra thicknesses or recesses, an extrusion billet is preformed (1) and compacted (2) by isostatic pressing then extruded (3) through a tube. The extrusion billet is made of water minus two materials, a forming material (21) and a tubular material (22). Forming material is applied to or inserted into a preformed body of tubular material or vice versa, before the body is compacted into an extrusion billet. According to another method, the tubular material and the forming material are introduced into a mold in a powder state and are compacted together to form an extrusion billet. During extrusion, the forming material causes bumps or recesses in the tubular material. After extrusion, the forming material (4) is removed, preferably by pickling.
Description
Claims
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE9001989A SE466340B (en) | 1990-06-05 | 1990-06-05 | SATISFIED TO MANUFACTURE PICTURES |
SE9001989 | 1990-06-05 | ||
PCT/SE1991/000299 WO1991018689A1 (en) | 1990-06-05 | 1991-04-26 | Method of manufacturing tubes |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0532598A1 true EP0532598A1 (en) | 1993-03-24 |
EP0532598B1 EP0532598B1 (en) | 1995-08-30 |
Family
ID=20379666
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP91910864A Expired - Lifetime EP0532598B1 (en) | 1990-06-05 | 1991-04-26 | Method of manufacturing tubes |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0532598B1 (en) |
DE (1) | DE69112621T2 (en) |
SE (1) | SE466340B (en) |
WO (1) | WO1991018689A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
RU2492965C1 (en) * | 2012-03-12 | 2013-09-20 | Лев Анатольевич Губенко | Method of forming long-length hollow articles from powders and plasticised materials and device to this end (versions) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0839589A1 (en) * | 1996-11-04 | 1998-05-06 | Alusuisse Technology & Management AG | Method for producing a metallic profiled strand |
ITUD20050002A1 (en) * | 2005-01-18 | 2006-07-19 | Dada Srl | process for making a spacer element for a panel of a thermal radiator, and a spacer element thus made |
CN103785706A (en) * | 2014-02-12 | 2014-05-14 | 攀钢集团江油长城特殊钢有限公司 | Manufacturing method of alloy steel section tubes |
CN105880609B (en) * | 2016-04-11 | 2018-06-26 | 哈尔滨建成集团有限公司 | The moulding technique and molding die of a kind of engine jet pipe |
DE102018202941B4 (en) * | 2018-02-27 | 2024-01-25 | Kennametal Inc. | Process for producing a blank from extrusion mass and extruder |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE413995B (en) * | 1977-02-07 | 1980-07-07 | Asea Ab | PRESSURE FOR HYDROSTATIC STRESS PRESSURE OF RODS |
-
1990
- 1990-06-05 SE SE9001989A patent/SE466340B/en not_active IP Right Cessation
-
1991
- 1991-04-26 DE DE69112621T patent/DE69112621T2/en not_active Expired - Fee Related
- 1991-04-26 EP EP91910864A patent/EP0532598B1/en not_active Expired - Lifetime
- 1991-04-26 WO PCT/SE1991/000299 patent/WO1991018689A1/en active IP Right Grant
Non-Patent Citations (1)
Title |
---|
See references of WO9118689A1 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
RU2492965C1 (en) * | 2012-03-12 | 2013-09-20 | Лев Анатольевич Губенко | Method of forming long-length hollow articles from powders and plasticised materials and device to this end (versions) |
Also Published As
Publication number | Publication date |
---|---|
SE9001989L (en) | 1991-12-06 |
DE69112621T2 (en) | 1996-05-02 |
DE69112621D1 (en) | 1995-10-05 |
EP0532598B1 (en) | 1995-08-30 |
SE9001989D0 (en) | 1990-06-05 |
WO1991018689A1 (en) | 1991-12-12 |
SE466340B (en) | 1992-02-03 |
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