EP0114280B1 - Procédé de fabrication d'éléments abrasifs - Google Patents

Procédé de fabrication d'éléments abrasifs Download PDF

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Publication number
EP0114280B1
EP0114280B1 EP83112342A EP83112342A EP0114280B1 EP 0114280 B1 EP0114280 B1 EP 0114280B1 EP 83112342 A EP83112342 A EP 83112342A EP 83112342 A EP83112342 A EP 83112342A EP 0114280 B1 EP0114280 B1 EP 0114280B1
Authority
EP
European Patent Office
Prior art keywords
mixture
grinding
synthetic resin
hardening
binder
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.)
Expired
Application number
EP83112342A
Other languages
German (de)
English (en)
Other versions
EP0114280A2 (fr
EP0114280A3 (en
Inventor
Karl Dr.Dipl.-Chem. Elbel
Rainer Augustin
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.)
Carborundum Schleifmittelwerke Te Duesseldorf GmbH
Original Assignee
DR ELBEL SCHLEIFMITTEL GmbH
Carborundum Schleifmittelwerke GmbH
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=6188838&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0114280(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by DR ELBEL SCHLEIFMITTEL GmbH, Carborundum Schleifmittelwerke GmbH filed Critical DR ELBEL SCHLEIFMITTEL GmbH
Priority to AT83112342T priority Critical patent/ATE45908T1/de
Publication of EP0114280A2 publication Critical patent/EP0114280A2/fr
Publication of EP0114280A3 publication Critical patent/EP0114280A3/de
Application granted granted Critical
Publication of EP0114280B1 publication Critical patent/EP0114280B1/fr
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B24D3/34—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents characterised by additives enhancing special physical properties, e.g. wear resistance, electric conductivity, self-cleaning properties
    • B24D3/342—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents characterised by additives enhancing special physical properties, e.g. wear resistance, electric conductivity, self-cleaning properties incorporated in the bonding agent
    • B24D3/344—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents characterised by additives enhancing special physical properties, e.g. wear resistance, electric conductivity, self-cleaning properties incorporated in the bonding agent the bonding agent being organic
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B24D3/02—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent
    • B24D3/20—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially organic
    • B24D3/28—Resins or natural or synthetic macromolecular compounds

Definitions

  • the invention relates to a method for producing grinding wheels in a casting mold using a mixture of abrasive grains, a cold-curing, thermoplastic synthetic resin as a binder, as well as additives and a starter system, such as. B. an organic peroxide and a tertiary amine, and with hardening of the mixture to form the grinding wheel in the mold.
  • Such methods are used for the production of hard abrasive particles, i. H. Grinding wheels, slip rings, cups, honing tools etc.
  • the known hard abrasives are made using ceramic, phenolic, magnesite or epoxy binders (the less commonly used binders such as metal, silicate, polyester and others are disregarded).
  • Ceramic-bonded grinding wheels are mainly used in precision grinding. Because of the fact that they are burned for several days, they are expensive to produce at temperatures above 900 ° C. In addition, because of the warping that occurs during firing, these bodies must be provided with a considerable excess, which necessitates appropriate reworking.
  • the phenolic resin bond is based on the simultaneous use of phenolic resoles and novolaks.
  • curing for up to two days at temperatures around 175 ° C is also an environmental burden in that considerable amounts of free phenol, formaldehyde and ammonia are released in addition to water.
  • free phenol, formaldehyde and ammonia are released in addition to water.
  • the structure of the abrasive body is porous, to be precise porous in the coarse grain area and less porous in the fine area. It is difficult, if not impossible, to adjust the abrasive density to the respective use in the case of such abrasives over the entire grit spectrum and to provide a sufficient chip gap volume, particularly in the fine and fine grain range.
  • the phenolic resin bond has the disadvantage that it is not very resistant to the alkaline coolants, which is why this bond is mainly used only in dry grinding.
  • magnesite bonded abrasives are manifold. So they are only approved for working speeds up to 20 m / sec, furthermore they change their hardness over time, so that they can only be used optimally in the period from 1 month to 4 months after production.
  • a significant disadvantage is the magnesium chloride liberated during grinding, which leads to severe corrosion, in particular to the protective hoods of the machines, and represents a considerable pollution of the wastewater.
  • epoxy resin formation has become increasingly common in recent years, particularly in the cutlery industry with lower stock removal rates and in the fine grain area.
  • a handicap of epoxy resins is their high viscosity.
  • Base resins with a high proportion of reactive thinners are available with viscosities of approx. 1 000 mPa.s, but they show insufficient heat resistance due to the thinning. That is why such abrasives always compromise between sufficient castability, resin content (which is inevitably 40% by weight and higher), heat resistance and performance. Because of these necessary compromises with regard to heat resistance, such grinding tools can only be used in wet grinding.
  • thermoplastic synthetic resin is used as a binder
  • the flowability should, owing to the low viscosity of the mixture, be sufficient to fill the mixture without further ado in the casting mold, but this is followed by compression, for example by shaking must to prevent the formation of too large voids in the mold.
  • the invention solves this problem in that metal or amine soaps are added to the binder grinding mixture, and the granulometric composition of this mixture corresponds to the respective Fuller curve, as a result of which a thixotropic mixture with the densest possible packing of its inorganic constituents is created by using the binder Synthetic resin or the monomer or mixture of monomers used to form the synthetic resin has a dynamic viscosity of less than 10 mPa.s, and that this mixture is liquefied, for example by vibration, and poured into the casting mold.
  • Schleifkom-filler-binder mixtures are strongly thixotropic due to their composition according to the invention and can be easily liquefied by vibration. With appropriate vibration, their consistency is such that they easily pass the outlet of a funnel and fill even complicated molds cleanly. It is possible, for example, to manufacture cup wheels with a wall thickness of only 3 mm and a cup diameter of 250 mm, which is not possible with the binders known to date.
  • the addition of the starter system can be metered in such a way that a sufficient pot life is achieved, but the hardened grinding wheel can be removed from the mold no later than two hours after the start of filling and the hardening takes place essentially at room temperature. Only in the case of small grinding wheels, where the large relative mold volume inevitably absorbs a lot of reaction heat compared to the small relative grinding wheel volume, it is advisable to warm the molds to 60 ° C briefly before or after filling.
  • the starter system expediently consists of an organic peroxide and an aromatic tertiary amine. It has proven advantageous to add a powdered organic peroxide to polymeric methacrylate and to dissolve the aromatic tertiary amine in the binder.
  • the hardening shrinkage of the abrasive articles produced according to the invention is extremely low and averages 0.02%. This fact makes it possible to design the respective shape in such a way that the parts of the grinding wheel which are in contact with the shape no longer have to be machined. This even applies to the bore, provided that the bore dome has a correspondingly small excess. Compared to the known methods, considerable manufacturing costs can be saved.
  • the abrasive bodies show practically no imbalance and no differences in density or hardness within the finished body, provided that the casting mold is geometrically perfect.
  • thermoplastics can be used for the production of hard abrasive articles, the polymerization being carried out from the monomer in the abrasive article mixture in the casting mold, the monomers optionally being stabilized with 3 to 20 ppm hydroquinone or other.
  • monomers are mainly methacrylic acid esters and / or vinyl acetate in question, other monomers are conceivable alone or as an additive, but it must be taken into account that some of the other monomers in question are unsafe in terms of work hygiene.
  • the binder according to the invention expediently contains bifunctional or trifunctional methacrylates as crosslinking agent (“crosslinking agent”).
  • Fillers are required to create the necessary chip gap volume and to enable polymerization. On the one hand, these fillers must be softer than the materials to be machined, but on the other hand they must be so pressure-resistant that they fix the grinding bodies rigidly and give the grinding body as a whole the necessary hardness.
  • Fillers that offer a Mohs hardness of less than 6 or Knoop of less than 500 are available here, are available in different grain sizes and are environmentally friendly, and possibly due to the abrasive grain Refine the micrograph created as a polishing agent.
  • Water-insoluble calcium compounds such as calcite, dolomite, aragonite, gypsum, selenite and / or screed gypsum, are preferred here.
  • the granulometric composition of the Schleifkom-filler combination should essentially correspond to the respective fuller curve. This ensures that the inorganic constituents are packed as densely as possible.
  • the fuller curve begins, for example, in the range of 150 ... 60 ⁇ m with a grinding-neutral filler, the range 60 ... 20 ⁇ m the Schieifkom 280 F, and subsequently of 20 ... 2 ⁇ m again a neutral filler. It is expedient that the fillers are surface-treated, primarily in the fine range 20 ... 2 ⁇ m.
  • the binder content is 16% by weight or 40% by volume. This is to say that the "hardness can be adjusted to the respective use here in a similar way to the abrasive grits of hard bonds, where one speaks of" hard and “soft” ceramic or Bakelite discs. Here is with the «hardness» more or less. the strength of the comein bond meant.
  • the abrasive articles according to the invention must be essentially leakproof.
  • grinding heat-sensitive steels it can be useful to create a more open surface of the grinding wheel to take away more water-based coolant. This is done very well by adding water-soluble powder substances.
  • ground water glass is ideal, which not only has a corrosion-inhibiting effect, but is also environmentally friendly and does not impair the coolant.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Polishing Bodies And Polishing Tools (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Claims (7)

1. Procédé de fabrication de meules dans un moule, avec mise en oeuvre d'un mélange de particules abrasives, d'une résine thermoplastique durcissant à froid en tant que liant ainsi que d'adjuvants et d'un système d'amorçage, par exemple un peroxyde organique et une amine tertiaire, et avec durcissement du mélange pour la formation de la meule dans le moule, caractérisé en ce qu'au mélange de liant et de particules abrasives sont ajoutés des savons métalliques ou aminiques, que la composition granulométrique de ce mélange correspond à la courbe de Fuller respective, ce qui donne un mélange thixotrope avec la plus grande densité de tassement possible de ses constituants inorganiques ; que la résine synthétique utilisée comme liant et respectivement le monomère et mélange de monomères mis en oeuvre pour la réalisation de la résine synthétique présente une viscosité dynamique inférieure à 10 mPa.s, et que ce mélange est liquéfié, par exemple, par vibration et versé dans le moule.
2. Procédé selon la revendication 1, caractérisé en ce qu'il utilise essentiellement comme liant des liquides polymérisables, par exemple de l'acétate vinylique et/ou du méthacrylate.
3. Procédé selon la revendication 1, caractérisé en ce que le durcissement se fait à une température ambiante pouvant atteindre au maximum 60 °C.
4. Procédé selon la revendication 1, caractérisé en ce qu'il utilise comme agent de réticulation (crosslinking agent) une résine méthacrylique contenant des méthacrylates bi-fonctionnels ou tri-fonctionnels.
5. Procédé selon la revendication 1, caractérisé en ce qu'il utilise comme adjuvant des matières de remplissage d'une dureté Knoop inférieure à 500.
6. Procédé selon la revendication 5, caractérisé en ce que les matières de remplissage ont subi, du moins partiellement, un traitement de surface.
7. Procédé selon la revendication 5, caractérisé en ce qu'il utilise comme matières de remplissage la calcite, la dolomie, l'aragonite, le gypse, la sélénite et/ou du plâtre à planchers.
EP83112342A 1983-01-21 1983-12-08 Procédé de fabrication d'éléments abrasifs Expired EP0114280B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83112342T ATE45908T1 (de) 1983-01-21 1983-12-08 Verfahren zur herstellung von schleifkoerpern.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19833301925 DE3301925A1 (de) 1983-01-21 1983-01-21 Verfahren zur herstellung von schleifkoerpern
DE3301925 1983-01-21

Publications (3)

Publication Number Publication Date
EP0114280A2 EP0114280A2 (fr) 1984-08-01
EP0114280A3 EP0114280A3 (en) 1985-09-18
EP0114280B1 true EP0114280B1 (fr) 1989-08-30

Family

ID=6188838

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83112342A Expired EP0114280B1 (fr) 1983-01-21 1983-12-08 Procédé de fabrication d'éléments abrasifs

Country Status (4)

Country Link
US (1) US4541843A (fr)
EP (1) EP0114280B1 (fr)
AT (1) ATE45908T1 (fr)
DE (2) DE3301925A1 (fr)

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4681600A (en) * 1984-09-05 1987-07-21 Extrude Hone Corporation Cutting tool fabrication process
US4662897A (en) * 1986-02-11 1987-05-05 Arkansas Hones Inc. Vitrified composite novaculite and process for producing same
US4736548A (en) * 1986-02-11 1988-04-12 Arkansas Hones, Inc. Vitrified composite washita stone and process for producing same
EP0242410B1 (fr) * 1986-04-17 1990-06-06 Carborundum Schleifmittelwerke GmbH Procédé de fabrication d'un élément abrasif élastique
EP0280756B1 (fr) * 1987-03-06 1990-06-27 Carborundum Schleifmittelwerke GmbH Procédé pour modifier le rendement de meulage des outils de meulage et d'alésage
US4828583A (en) * 1987-04-02 1989-05-09 Minnesota Mining And Manufacturing Company Coated abrasive binder containing ternary photoinitiator system
US5116392A (en) * 1988-12-30 1992-05-26 Tyrolit - Schleifmittelwerke Swarovski K.G. Abrasive article and abrasive
AT392604B (de) * 1989-01-30 1991-05-10 Steirische Magnesit Ind Ag Verfahren zur herstellung von schleifkoerpern
US5209023A (en) * 1990-05-18 1993-05-11 Jerry Bizer Thermoplastic polymer optical lap and method of making same
US5089032A (en) * 1990-07-05 1992-02-18 Moran Joseph F Grinding wheel
NL9300919A (nl) * 1993-05-28 1994-12-16 Terra Ijssel Bv Werkwijze voor het verwerken van afvalstoffen.
NL9300927A (nl) * 1993-05-28 1994-12-16 Terra Ijssel Bv Werkwijze voor het verwerken van afvalstoffen en met de werkwijze verkregen lichaam.
DE9411326U1 (de) * 1994-07-13 1994-09-15 Zahnradpraezision Horst Reinek Verzahntes Honschleifwerkzeug
DE19614401B4 (de) * 1996-04-12 2004-08-19 Saint-Gobain Diamantwerkzeuge Gmbh & Co. Kg Belag für Schleif- und Honwerkzeuge
US5779529A (en) * 1996-11-25 1998-07-14 Bizer Industries Thermoplastic optical lap with reinforced webbing
US6050573A (en) * 1998-09-30 2000-04-18 Kwikee Products Co., Inc. Automatic leveling system for vehicles
JP2000351960A (ja) * 1999-06-10 2000-12-19 Nisca Corp 研削用砥粒体
CN102699826A (zh) * 2012-06-16 2012-10-03 大连理工大学 一种常温固化结合剂软磨料砂轮

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2242344A1 (en) * 1973-08-30 1975-03-28 Touati Roger Mortar bonded with a urea resin - and set rapidly with vibration and-or centrifuging to give high strength

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1194373A (fr) * 1959-11-09
US2189733A (en) * 1938-01-28 1940-02-06 Norton Co Resin bonded abrasive article
US2901337A (en) * 1956-07-31 1959-08-25 Union Carbide Corp Abrasive articles and method of making the same
US2943926A (en) * 1958-07-18 1960-07-05 Cincinnati Milling Machine Co Abrasive wheel composition
FR1257770A (fr) * 1960-02-24 1961-04-07 Somata Sa Produit abrasif et son procédé de fabrication
US3208836A (en) * 1960-09-09 1965-09-28 Borden Co Cold press method of making abrasive articles
DE2028891A1 (en) * 1970-06-12 1971-12-16 Gold U Silberscheideanstalt De Abrasive articles - contng acrylic resins as binders
CH532452A (de) * 1970-07-02 1973-01-15 Esterol Ag Verfahren zur Herstellung von kunstharzgebundenen Formkörpern, insbesondere von polyestergebundenen Schleifkörpern
NL7013165A (fr) * 1970-09-05 1972-03-07

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2242344A1 (en) * 1973-08-30 1975-03-28 Touati Roger Mortar bonded with a urea resin - and set rapidly with vibration and-or centrifuging to give high strength

Also Published As

Publication number Publication date
DE3380484D1 (en) 1989-10-05
ATE45908T1 (de) 1989-09-15
US4541843A (en) 1985-09-17
EP0114280A2 (fr) 1984-08-01
DE3301925A1 (de) 1984-07-26
EP0114280A3 (en) 1985-09-18

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