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WO1991004149A1 - Methode pour comprimer la limaille en briquettes - Google Patents

Methode pour comprimer la limaille en briquettes Download PDF

Info

Publication number
WO1991004149A1
WO1991004149A1 PCT/GB1990/001439 GB9001439W WO9104149A1 WO 1991004149 A1 WO1991004149 A1 WO 1991004149A1 GB 9001439 W GB9001439 W GB 9001439W WO 9104149 A1 WO9104149 A1 WO 9104149A1
Authority
WO
WIPO (PCT)
Prior art keywords
briquettes
briquette
swarf
face
billet
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.)
Ceased
Application number
PCT/GB1990/001439
Other languages
English (en)
Inventor
Antonino Giorgio Cacace
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Camborne Industries PLC
Original Assignee
Camborne Industries PLC
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Camborne Industries PLC filed Critical Camborne Industries PLC
Publication of WO1991004149A1 publication Critical patent/WO1991004149A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B9/00—Presses specially adapted for particular purposes
    • B30B9/32—Presses specially adapted for particular purposes for consolidating scrap metal or for compacting used cars
    • B30B9/327—Presses specially adapted for particular purposes for consolidating scrap metal or for compacting used cars for briquetting scrap metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B30—PRESSES
    • B30B—PRESSES IN GENERAL
    • B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
    • B30B15/02—Dies; Inserts therefor; Mounting thereof; Moulds
    • B30B15/022—Moulds for compacting material in powder, granular of pasta form

Definitions

  • This invention relates to the compaction of scrap metal, particularly but not necessarily exclusively the compaction of scrap metal swarf into briquettes for the purpose of recycling.
  • swarf comprehends the off cuts from machining operations in general and is intended to include the off cuts from turning, boring, shaping and milling operations on engineering steels. The fine off cuts from some stamping and punching operations may also be suitable.
  • engineing steel is intended to describe those low alloy steels whi. are commonly subjected to machining operations including mild steel (a term which itself includes carbon steel), forging steel and axle or shaft steel all of which contain significant amounts of carbon.
  • British patent #1313545 there is disclosed, inter alia, a process in which steel swarf is pressed into compact masses (which for convenience will be called “briquettes").
  • the briquettes are pressed together and jacketed in a closed tube, usually of steel or stainless steel.
  • the billet so formed is then heated and worked by a process such as rolling into a finished or semi-finished product.
  • briquettes may take place in a cavity die prior to being jacketed.
  • briquettes may be formed directly in the bore of the tube.
  • the tube is inserted in a supporting die during the compaction process and the bore of the tube serves as the cavity.
  • the compaction is carried out by means of a press having a ram which presses a quantity of the swarf previously inserted in the cavity into a briquette.
  • the ram is then withdrawn and a new charge of swarf is inserted in the cavity.
  • the ram is again inserted in the cavity to form a new briquette pressed up against the earlier formed briquette.
  • the cycle is repeated until the cavity is substantially filled up with briquettes.
  • the oxides on the swarf inside the jacketing tube are reduced and during the working process the metal particles of which the briquettes are composed are consolidated into a unitary mass which are sintered to each other and to the jacket.
  • the reduction of oxides on the swarf occurs as a result of the combination thereof with carbon which is either introduced into the jacket or which diffuses out of the steel or other metal of which the swarf is composed.
  • the jacketing tube serves to maintain reducing conditions within the billet. Attempts to produce an acceptable hot worked product from a billet of unjacketed swarf have been unsuccessful even when great care was taken to try to prevent atmospheric oxygen from getting to the hot billet.
  • the ram has an end face which comes into contact with the swarf in the cavity. In the rams which have been used up to the present time this face has been flat and perpendicular to the axis of the cavity. Consequently each briquette has effectively a pair of mutually parallel faces. Because they are formed one by contact with the end face of the ram and the other by contact with the flat end face of the adjacent briquette formed earlier in the cavity, these parallel faces are also flat and perpendicular to the axis of the cavity.
  • FIG. 1 of the accompanying drawings is a diagrammatic cross-sectional side view of a billet being rolled.
  • the billet 10 comprises briquettes 12 in a tubular jacket 14.
  • the billet is passing through rolls 16.
  • the briquettes passing through the rolls are shown separating at the interface 18.
  • the result of the separation is the formation of voids under the wall of the tube.
  • the lack of contact with the hot solid mass of the briquettes causes rapid cooling of the tube at these points.
  • a method of forming a billet comprising first and second briquettes of swarf which are joined at adjacent faces, characterised in that the adjacent faces are formed with complementary interengaging formations.
  • the method includes the steps of inserting a first charge of swarf into a pressing cavity, causing a pressing head to press the first charge of swarf to form the first briquette with a back face which conforms to the shape of a working face of the pressing head which comes into contact with the swarf, inserting a second charge of swarf into the pressing cavity, and causing the pressing head to press the second charge of swarf against the back face of the first briquette to form the second briquette, characterised in that the back face of the first briquette and the front face of the second briquette are formed with complementary interengaging formations.
  • the billet comprises a metal jacket in which the swarf is pressed to form the briquettes.
  • the formation in the back face of the first briquette comprises an annular recess.
  • the formation comprises an axially projecting protuberance.
  • the briquettes and the said formation have a common axis of symmetry.
  • the said formation is substantially of frusto-conical shape.
  • the back face has a substantially flat peripheral portion around the said formation the longitudinal axis of the briquette being normal to the peripheral portion.
  • the angle at the imaginary apex of the frusto-conical shaped formation is advantageously between 30 and 120 degrees.
  • the frusto-conical shaped formation has a depth not greater than half of the diameter of the briquettes.
  • a billet comprising first and second briquettes of swarf which are joined at adjacent faces, characterised in that the adjacent faces are formed with complementary interengaging formations.
  • Figure 2 is a cross-sectional side view of part of a billet being rolled
  • Figure 3 is a side view of a nose piece mounted on the end of a ram
  • Figure 4 is a cross-sectional side view of a second nose piece in the process of forming a billet
  • Figure 5 is a cross-sectional side view of yet another nose piece.
  • Figures 6 and 7 are cross-sectional side views of billets formed by rams with the nose pieces illustrated in Figures 3 and 5 respectively.
  • a billet 30 comprising briquettes 32 (of, for example, mild steel shavings) jacketed in a tube 34 (again, by way of example, of mild steel or stainless steel).
  • the briquettes 32 have conical interfaces as indicated at 38. These conical interfaces are formed by the head of the ram (shown in dotted outline at 40) which is inserted in the tube and forms each briquette.
  • the head of the ram has a conical end face 42.
  • the apex 44 of the end face lies on the longitudinal axis 46 of the ram and projects away from the ram.
  • the end face 42 of the ram forms in the briquette an end face 48 which is an inversion of the shape of the end face 42.
  • the shavings are pressed up against the end face 48 of the adjacent earlier formed briquette so that the two faces are formed with interlocking conical formations.
  • the conical end face 42 can be formed integrally with the ram which would ordinarily be hardened by any well known hardening process.
  • the end face can be embodied in a nose piece of wear resistant material such as tungsten which is brazed on the end of the ram.
  • the nose piece can be demountably fixed on the end of the ram. In this case the nose piece can be replaced at much lower cost than the whole ram.
  • the demountable nose piece can be fixed on the ram by means of a stud.
  • One such stud is indicated in dotted outline at 86 and may be threaded at each end in opposite senses, one end being screwed into the nose piece and the other into the ram.
  • the conical shape of the end of the nose piece 40 is very suitable for forming briquettes having interfaces which have a diminished tendency to separate under the action of the rolls.
  • the shape of the nose piece 60 shown in Figure 3 is considered more suitable in practice.
  • the tubular jacket (shown at 62 in Figure 3) is mounted in the close fitting cavity 64 of a die 66 during the operation of forming the briquettes therein.
  • the nose piece be made of wear resistant steel so it is advantageous to mount an annular collar 68 of wear resistant steel on the die, surrounding the entrance to the cavity 64.
  • the collar has a central aperture 70 the diameter of which is substantially equal to the diameter of the bore of the tube 62.
  • the nose piece is a close sliding fit in the aperture 70 and the bore of the tube.
  • the provision of the collar prevents the die from wearing around the entrance to the cavity and also acts as a guide for the nose piece as it enters the bore of the tube.
  • the nose piece is capable of shearing shavings trapped between the periphery 72 of the end face 74 and the periphery of the aperture 70 as the nose piece approaches the aperture. This shearing action is most efficient if the end face 74 meets the cylindrical face 76 of the nose piece at a right angle, indicated at A.
  • the periphery of the aperture 70 acts as a mating cutting edge.
  • end face 74 is provided with what is essentially a frusto-conical portion 78 which is set in from the periphery 72.
  • the portion 78 is symmetrical about the axis 80 of the nose piece.
  • end face 74 is provided with a modified conical portion and also, at its periphery, an annular portion 72 which is at right angles to the cylindrical face 76.
  • the width of the peripheral portion 72 which Is at right angles to the cylindrical face need not be more than about 1/8 of the diameter of the end face. In the example illustrated the width is 4 mm, the diameter of the end face being a 97.7 mm.
  • the end face 74 should be radiused where the frusto-conical portion 78 meets the peripheral portion 72 and also at the extremity 84 of the frusto-conical face 82. This not only prevents stress raisers from occurring in the nose piece in use but also sharp edges in the frusto- conical portion 78 can cause the nose piece to be wedged into the shavings being compacted causing difficulties in retracting the ram. This is thought to take place due to the elasticity of the shavings. Radii of as little as 6mm have been found adequate. However, in the example illustrated, the radius at the junction of the annular portion 72 and the frusto-conical face 82 is about 12 mm and the radius at the extremity 84 is about 25 mm.
  • the face 82 should not be too close to being right circular cylindrical. It is considered that the angle at the (imaginary) apex of the frusto-conical face 82 should be between 30 and 120 (indicated by the angle B). In the example illustrated angle B is 90°.
  • the axial length of the frusto-conical portion 78 should not be more than about half the diameter of the nose piece and is best between 0.2 and 0.5 thereof. In the example illustrated in Figure 3 the axial length is about 30 mm.
  • a nose piece 90 with a frusto-conical portion 92 having an axial length approximately equal to the diameter of the nose piece is shown in Figure 4, inserted in a tube and in the process of compacting a mass of shavings into a briquette. As the free end of the frusto-conical portion 92 enters the inversely shaped recess 94 in the face of the earlier formed briquette 96 shavings located therebetween begin to be compacted.
  • FIG. 5 there is shown a nose piece 110 having an end face 116 in which there is formed a recess 112 rather than a protuberance.
  • the recess 112 is again substantially frusto-conical.
  • the end face has a peripheral portion 114 which is at right angles to the cylindrical face 122. It will be clear that the face of a briquette formed by the nose piece 110 will have a protuberance (rather than a recess) which projects towards the nose piece.
  • a possible disadvantage of the nose piece 110 is that the forces applied thereto by the shavings during compaction, especially at the conical face 118 of the recess 112, will have radial components which may tend to force the zone of the nose piece surrounding the conical face outwardly. This may cause the nose piece 110 to fail due to fatigue at locations such as those indicated at 120.
  • Another advantage of using a nose-piece with a protuberance rather than a recess in the end face is that the nose piece with a protuberance is likely to produce a briquette in which the density of the swarf will be greater at the centre of the briquette than at the periphery thereof.
  • a highly compressed smooth surface at the periphery of a briquette is less likely to result in satisfactory interlocking between adjacent briquettes at the periphery thereof. This is important as it is this area which undergoes the greatest shearing stress during subsequent hot rolling.
  • a billet 200 is shown in Figure 6 comprising briquettes 202 formed by a press having two rams with nose pieces 60 is illustrated in Figure 3.
  • the rams are mounted in axial alignment with the tube 204 mounted in a supporting die located between the rams.
  • the rams are advanced cyclically into both ends of the tube at the same time.
  • a predetermined quantity of swarf is fed into each end of the tube between each cycle of the press.
  • a first briquette 202a is formed in the longitudinal centre of the tube.
  • two briquettes are formed, one by each ram, in each cycle.
  • the nose piece forms a frusto-conical recess 206 in the front face of each briquette which interlocks with a complementary protuberance 208 in the back face of the adjacent briquette.
  • the protuberance is formed by the swarf which fills up the recess in the process of being compacted.
  • the annular face 72 of the nose piece forms a complementary annular face 210 around the periphery of the front face.
  • the recess 206 and the protuberance 208 are surfaces of revolution having an axis of symmetry coincident with the longitudinal axis 212 of the billet.
  • the face 210 is normal to the axis 212.
  • billet comprises a jacketing tube which is typically of 89 mm internal diameter, 6 mm wall thickness and 100 or 200 cm long. Typically there would be about twenty four briquettes 202 in each metre length of tube after compacting.
  • the tube can be mild steel or stainless steel.
  • mild steel end pieces indicated at 204a, may be welded to the ends of the tube before it is filled with briquettes.
  • One advantage of using these end pieces is to reduce the cost of the billet.
  • the end pieces also promote better product quality and assist the entry of the billet into the rolls. Billets provided with the end pieces are more fully discussed in the applicant's PCT patent application entitled "Recycling Scrap Metal".
  • Figure 7 is an illustration, similar to Figure 6 of a billet 300 comprising a tube 302 filled with billets 304 using a press having two rams provided with nose pieces 110 as shown in Figure 5.
  • the nose piece forms a frusto-conical protuberance 306 in the front face of each briquette which interlocks with a complementary recess 308 in the back face of the adjacent briquette.
  • the annular face 114 of the nose piece forms a complementary annular face 310 around the periphery of the front face.
  • the recess 308 and the protuberance 306 are surfaces of revolution having an axis of symmetry coincident with the longitudinal axis 312 of the billet.
  • the face 310 is normal to the axis 312.
  • the invention may be employed to form a billet comprising briquettes prior to insertion in a jacket; for example the billet may be formed by pressing swarf into briquettes in a split cavity die. Improved cohesion between adjacent briquettes has the result that a greater degree of hot working or reduction from a larger diameter to finished size can be achieved more rapidly. Production time is reduced and smaller final sizes can be rolled. Furthermore strength requirements of the jacket are reduced enabling, for example, a larger range of tubing to be used. In the case of a billet formed prior to jacketing, greater cohesion between briquettes results in a billet which can sustain a far greater degree of rough handling before it will break up. It is also possible to produce a longer billet than has heretofore been the case.
  • the invention may usefully be applied to briquettes made up of swarf composed of engineering steels and also suitable high alloy steels such as stainless steel.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Forging (AREA)
  • Processing Of Solid Wastes (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
  • Press Drives And Press Lines (AREA)
  • Superconductors And Manufacturing Methods Therefor (AREA)
  • Metal Rolling (AREA)
  • Moulds, Cores, Or Mandrels (AREA)

Abstract

Méthode pour former une billette (30, 200, 300) en comprimant cycliquement des charges de limaille auxquelles on donne une forme de briquettes (32, 202, 304) jointes les unes aux autres. La billette peut aussi comprendre un tube (34, 204, 302) qui forme gaine autour des briquettes. Ces dernières sont reliées entre elles par des connexions dont les configurations s'engrènent les unes dans les autres de manière complémentaire (206, 208, 306, 308). Ces configurations peuvent être en forme de cône tronqué en position coaxiale par rapport aux briquettes. Chaque connexion peut avoir une partie périphérique en anneau quasiment plate (210, 310) verticale par rapport à l'axe longitudinal.
PCT/GB1990/001439 1989-09-21 1990-09-19 Methode pour comprimer la limaille en briquettes Ceased WO1991004149A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
NZ22841689 1989-09-21
NZ22841789 1989-09-21
NZ228417 1989-09-21

Publications (1)

Publication Number Publication Date
WO1991004149A1 true WO1991004149A1 (fr) 1991-04-04

Family

ID=26650843

Family Applications (2)

Application Number Title Priority Date Filing Date
PCT/GB1990/001438 Ceased WO1991004148A1 (fr) 1989-09-21 1990-09-19 Appareil pour compresser la limaille
PCT/GB1990/001439 Ceased WO1991004149A1 (fr) 1989-09-21 1990-09-19 Methode pour comprimer la limaille en briquettes

Family Applications Before (1)

Application Number Title Priority Date Filing Date
PCT/GB1990/001438 Ceased WO1991004148A1 (fr) 1989-09-21 1990-09-19 Appareil pour compresser la limaille

Country Status (11)

Country Link
EP (1) EP0501965B1 (fr)
JP (1) JP2913213B2 (fr)
KR (1) KR100212418B1 (fr)
AT (1) ATE123994T1 (fr)
AU (2) AU6433190A (fr)
CA (1) CA2066565C (fr)
DE (1) DE69020359T2 (fr)
DK (1) DK0501965T3 (fr)
ES (1) ES2078352T3 (fr)
WO (2) WO1991004148A1 (fr)
ZA (2) ZA907517B (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992001073A3 (fr) * 1990-07-12 1992-02-20 Camborne Ind Plc Procede de fabrication de produits metalliques utilisant de la ferraille
WO2000010801A1 (fr) * 1998-08-21 2000-03-02 Henkel Kommanditgesellschaft Auf Aktien Outil de compression a proprietes anti-adherence

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2700494B1 (fr) * 1993-01-15 1995-04-07 Sgn Soc Gen Tech Nouvelle Procédé et dispositif de compactage, particulièrement adaptés au compactage de matières dangereuses et notamment de déchets radioactifs.
KR100792846B1 (ko) * 2006-12-19 2008-01-14 주식회사 포스코 전기로의 스크랩 다짐장치
CN112808679A (zh) * 2020-12-24 2021-05-18 浙江永达电力科技有限公司 一种基于铁塔的边角料环保型再回收处理装置
CN113578992B (zh) * 2021-08-02 2025-06-20 常州徐沛金属材料有限公司 一种屑饼机用可重复利用的耐高温模筒

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2622510A (en) * 1948-05-12 1952-12-23 Walter W Letts Pressing sawdust into the form of bodies
DE1247002B (de) * 1963-05-29 1967-08-10 Vnii Nowych Str Materialow Verfahren und Vorrichtung zum Strangpressen von profilierten Erzeugnissen aus einem Gemisch von zerkleinerten Spaenen von Holzabfaellen, landwirtschaftlichen Abfallprodukten und aehnlichem Rohgut mit Polymerbindemitteln
US3909909A (en) * 1971-07-21 1975-10-07 Republic Steel Corp Harmonic press and method of forging
DE2524412A1 (de) * 1975-05-30 1976-12-30 Amsted Ind Inc Kontinuierliches verfahren und vorrichtung zur herstellung von stangen aus metallpulver
US4174933A (en) * 1977-12-27 1979-11-20 Combustion Engineering, Inc. Forming an extruded bar out of metal chips

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1609460A (en) * 1925-01-28 1926-12-07 Western Electric Co Apparatus for molding articles under high pressure
US1838518A (en) * 1927-02-17 1931-12-29 Simonds Worden White Company Knockdown mold
DE720296C (de) * 1938-11-03 1942-04-30 Waffen Und Munitionsfabriken A Presse zur Herstellung homogener Sprengstoffpresslinge unter hohem Druck
DE2122322A1 (de) * 1971-05-06 1972-11-23 Societa Italiana Per Azioni Per La Produzione Di Calci E Cementi Di Segni, Rom Preßform zum Herstellen von tablettenförmigen Pulverproben
JPS5028643A (fr) * 1973-07-17 1975-03-24
US4666389A (en) 1985-01-25 1987-05-19 The Texas A&M University System Apparatus for forming compacts from solid particles

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2622510A (en) * 1948-05-12 1952-12-23 Walter W Letts Pressing sawdust into the form of bodies
DE1247002B (de) * 1963-05-29 1967-08-10 Vnii Nowych Str Materialow Verfahren und Vorrichtung zum Strangpressen von profilierten Erzeugnissen aus einem Gemisch von zerkleinerten Spaenen von Holzabfaellen, landwirtschaftlichen Abfallprodukten und aehnlichem Rohgut mit Polymerbindemitteln
US3909909A (en) * 1971-07-21 1975-10-07 Republic Steel Corp Harmonic press and method of forging
DE2524412A1 (de) * 1975-05-30 1976-12-30 Amsted Ind Inc Kontinuierliches verfahren und vorrichtung zur herstellung von stangen aus metallpulver
US4174933A (en) * 1977-12-27 1979-11-20 Combustion Engineering, Inc. Forming an extruded bar out of metal chips

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992001073A3 (fr) * 1990-07-12 1992-02-20 Camborne Ind Plc Procede de fabrication de produits metalliques utilisant de la ferraille
WO2000010801A1 (fr) * 1998-08-21 2000-03-02 Henkel Kommanditgesellschaft Auf Aktien Outil de compression a proprietes anti-adherence

Also Published As

Publication number Publication date
EP0501965A1 (fr) 1992-09-09
DE69020359T2 (de) 1997-05-22
KR100212418B1 (ko) 1999-08-02
CA2066565A1 (fr) 1991-03-22
ATE123994T1 (de) 1995-07-15
ZA907517B (en) 1991-06-26
ZA907515B (en) 1991-07-31
WO1991004148A1 (fr) 1991-04-04
EP0501965B1 (fr) 1995-06-21
AU6341390A (en) 1991-04-18
DE69020359D1 (de) 1995-07-27
KR927003322A (ko) 1992-12-17
DK0501965T3 (da) 1995-10-16
AU6433190A (en) 1991-04-18
ES2078352T3 (es) 1995-12-16
JPH05500635A (ja) 1993-02-12
AU654469B2 (en) 1994-11-10
JP2913213B2 (ja) 1999-06-28
CA2066565C (fr) 2002-09-17

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