GB2202218A - Method of making an article from pyrophyllite - Google Patents

Method of making an article from pyrophyllite Download PDF

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Publication number
GB2202218A
GB2202218A GB08803809A GB8803809A GB2202218A GB 2202218 A GB2202218 A GB 2202218A GB 08803809 A GB08803809 A GB 08803809A GB 8803809 A GB8803809 A GB 8803809A GB 2202218 A GB2202218 A GB 2202218A
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GB
United Kingdom
Prior art keywords
article
pyrophyllite
isostatic pressing
mould
powder form
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
Application number
GB08803809A
Other versions
GB2202218B (en
GB8803809D0 (en
Inventor
Victor Richard Conradi
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.)
De Beers Industrial Diamond Division Pty Ltd
Original Assignee
De Beers Industrial Diamond Division Pty Ltd
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 De Beers Industrial Diamond Division Pty Ltd filed Critical De Beers Industrial Diamond Division Pty Ltd
Publication of GB8803809D0 publication Critical patent/GB8803809D0/en
Publication of GB2202218A publication Critical patent/GB2202218A/en
Application granted granted Critical
Publication of GB2202218B publication Critical patent/GB2202218B/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/16—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay
    • C04B35/18—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silicates other than clay rich in aluminium oxide
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
    • B22D41/50—Pouring-nozzles
    • B22D41/52—Manufacturing or repairing thereof
    • B22D41/54—Manufacturing or repairing thereof characterised by the materials used therefor

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Ceramic Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Compositions Of Oxide Ceramics (AREA)

Abstract

A method of making an article to be used in the processing of a molten non-ferrous metal, such as a teeming nozzle, includes the steps of placing a suitable quantity of pyrophyllite in powder form into a mould for the article, isostatically pressing the powder in the mould, either by wet isostatic pressing or by dry isostatic pressing, to form the article, and then removing the article from the mould. Utilising the method of invention, an article may be made which does not need to be sintered before use.

Description

METHOD OF. MAKING AN ARTICLE FROM PYROPHYLLITE BACKGROUND OF THE INVENTION This invention relates to a method of making an article to be used in the processing of a molten non-ferrous metal from pyrophyllite and to the article so made.
Articles to be used in the processing of molten non-ferrous metals, such as teeming nozzles, are generally made of either silicon carbide or aluminium oxide. These articles are made by uniaxially pressing the silicon carbide or aluminium oxide in powder form and then sintering the article. Such articles must have a 12 to 15 percent porosity as a safeguard against thermal shock.
There is a need for articles of this type which can be made from different types of materials, without the need for sintering, and which are thus cheaper to produce.
SUMMARY OF THE INVENTION According to the invention there is provided a method of making an article to be used in the processing of a molten non-ferrous metal including the steps of: (a) placing a suitable quantity of pyrophyllite in powder form into a mould for the article; (b) isostatically pressing the powder to form the article; and (c) removing the article from the mould.
By "a suitable quantity" of pyrophyllite in powder form, there is meant sufficient pyrophyllite in powder form to fill the mould to the level required for the production of the article. Obviously, the amount of pyrophyllite in powder form used will vary according to the article being produced and to the size of the article being produced.
Preferably, the pyrophyllite in powder form has an average particle size of from 1 to 1000 microns.
In step (b) of the method of the invention, the isostatic pressing may be wet isostatic pressing or dry isostatic pressing. The isostatic pressing is preferably carried out at a pressure of from 4000 to 40000psig (27,7-276,0 MPa).
According to another aspect of the invention there is provided an article to be used in the processing of a molten non-ferrous metal made from pyrophyllite in powder form by isostatic pressing in a mould.
According to a further aspect of the invention, there is provided pyrophyllite for use in a method of making an article to be used in the processing of a molten non-ferrous metal.
DESCRIPTION OF PREFERRED EMBODIMENTS The crux of the present invention is that an article to be used in the processing of a molten non-ferrous metal is made from pyrophyllite. The pyrophyllite is preferably blue-grey compact cryptocrystalline pyrophyllite, commonly known as "wonderstone" available from Gestoptefontein in the South Western Transvaal, South Africa. An analysis of wonderstone is given below.
SiO 58,45 2 TiO2 2,35 Al203 31,27 Fe203 O, 84 FeO MnO MgO 0,12 CaO 0,05 aha20 0,30 K20 0,16 P205 H20+ 4,88 H20- 0,23 Total : 100,08 1,534 A 1,586 y 1,596 2vv 60+ 50 D 2,84 For use in the method of the invention, the pyrophyllite must be in powder form, preferably having an average particle size of from 1 to 1000 microns. This powder form may be produced for example, by crushing the pyrophyllite, typically to a particle size of the order of 0,025 mm, adding an alcohol such as polyvinylalcohol and adding a suitable binder such as a wax emulsion and then spray drying the mixture. This method typically produces particles of size 0,3 to 0,125 mm.An alternative method of producing the powder form is to crush the pyrophyllite, calcine the crushed pyrophyllite, typically at a temperature of the order of 8500C for a period of several hours, mix the crushed product with waterglass, dry the mixture and remove or crush any agglomerates. Pyrophyllite powder of a coarser size, typically of the order of 0,5 mm, is produced by this method.
The article of the invention may be any article used in the processing of a molten non-ferrous metal. The article may be for example a teeming no;zle or a section of a lining for a vessel or the like. The article is only for use with non-ferrous metals such as aluminium, bronze, zinc and copper.
According to the method of the invention, a suitable quantity of the pyrophyllite in powder form is placed in a mould for the article.
For example, where the article to be produced is a teeming nozzle, the powder may be placed in a mould comprising an outer wall of a flexible rubber material with an inner core of a rigid material.
The powder is placed in the mould between the rigid core and the outer flexible rubber wall. The pyrophyllite powder is then isostatically pressed, using either wet isostatic pressing or dry isostatic pressing. Generally, a pressure of about 25 000 psig (172,5 MPa) is used.
Once the article is removed from the mould, it is ready for use.
There is no need for sintering of the article.
The article is suitable for use in the processing of molten nonferrous metals.

Claims (11)

1.
A method of making an article to be used in the processing of a molten non-ferrous metal includes the steps of; (a) placing a suitable quantity of pyrophyllite in powder form into a mould for the article; (b) isostatically pressing the powder to form the article; and (c) removing the article from the mould.
2.
A method according to claim 1 wherein the pyrophyllite is blue-grey compact cryptocrystalline pyrophyllite.
3.
A method according to claim 1 or claim 2 wherein the pyrophyllite in powder form has an average particle size of from 1 to 1000 microns.
4.
A method according to any one of claims 1 to 3 wherein in step (b) the isostatic pressing is wet isostatic pressing.
5.
A method according to any of claims 1 to 3 wherein in step (b) the isostatic pressing is dry isostatic pressing.
6.
A method according to any one of claims 1 to 5 wherein in step (b) the isostatic pressing is carried out at a pressure of from 4000 to 40000psig (27,7-276,0 MPa).
7.
A method according to any one of claims 1 to 6 wherein the article is a teeming nozzle.
8.
A method according to any one of claims 1 to 6 wherein the article is a section of a lining for a vessel adapted to hold a molten nonferrous metal.
9.
An article for use in the processing of a molten non-ferrous metal made from pyrophyllite in powder form by isostatic pressing in a mould.
10.
Pyrophyllite for use in a method of making an article to be used in the processing of a molten non-ferrous metal.
11.
A method according to claim 1 substantially as herein described.
GB8803809A 1987-02-19 1988-02-18 Method of making an article from pyrophyllite Expired - Lifetime GB2202218B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
ZA871222 1987-02-19

Publications (3)

Publication Number Publication Date
GB8803809D0 GB8803809D0 (en) 1988-03-16
GB2202218A true GB2202218A (en) 1988-09-21
GB2202218B GB2202218B (en) 1991-02-06

Family

ID=25578768

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8803809A Expired - Lifetime GB2202218B (en) 1987-02-19 1988-02-18 Method of making an article from pyrophyllite

Country Status (1)

Country Link
GB (1) GB2202218B (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0846514A1 (en) * 1996-12-05 1998-06-10 Akechi Ceramics Kabushiki Kaisha A continuous casting nozzle for casting molten steel
EP1097763A1 (en) * 1999-04-05 2001-05-09 Akechi Ceramics Kabushiki Kaisha Continuous casting nozzle
EP1101549A1 (en) * 1999-04-09 2001-05-23 Akechi Ceramics Kabushiki Kaisha Continuous casting nozzle

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114620739B (en) * 2022-03-30 2023-08-25 浙江省地质院 Nanometer lamellar pyrophyllite powder and preparation method thereof

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB231469A (en) * 1925-03-14 1926-06-14 Heinrich Oexmann A process for the manufacture of durable earthenware
GB742963A (en) * 1953-05-06 1956-01-04 Utica Drop Forge And Tool Corp Method of forming articles from comminuted material, and articles made therefrom
GB758786A (en) * 1953-08-20 1956-10-10 Utica Drop Forge And Tool Corp Moulds for forming hollow articles, e.g. die inserts
GB1109725A (en) * 1965-05-14 1968-04-10 Aug Gundlach G M B H Method and apparatus for producing shaped members from a mouldable refractory material
GB1165384A (en) * 1966-09-03 1969-09-24 Willan Ltd G L Improvements in or relating to Refractory Articles
GB1180298A (en) * 1967-09-11 1970-02-04 Peter Frank Rossmann Improvements in or relating to Apparatus and Method for Pressurizing Materials
GB1200522A (en) * 1965-02-23 1970-07-29 Coors Porcelain Co Improvements in or relating to a method for manufacturing articles from compactable materials
GB1265993A (en) * 1969-01-27 1972-03-08
GB1300864A (en) * 1969-03-03 1972-12-20 Asea Ab Method of sintering powder bodies
GB1321451A (en) * 1970-01-15 1973-06-27 Foseco Int Production of refractory articles
GB1339483A (en) * 1970-09-07 1973-12-05 Miki M Method for producing liners for feeder heads used in metal casting and an apparatus therefore
GB1387415A (en) * 1971-07-28 1975-03-19 Lucas Industries Ltd Method of and apparatus for producing a hot pressed component
GB1449349A (en) * 1973-06-25 1976-09-15 Nat Forge Co Mould apparatus for isostatic pressing of hollow parts

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB231469A (en) * 1925-03-14 1926-06-14 Heinrich Oexmann A process for the manufacture of durable earthenware
GB742963A (en) * 1953-05-06 1956-01-04 Utica Drop Forge And Tool Corp Method of forming articles from comminuted material, and articles made therefrom
GB758786A (en) * 1953-08-20 1956-10-10 Utica Drop Forge And Tool Corp Moulds for forming hollow articles, e.g. die inserts
GB1200522A (en) * 1965-02-23 1970-07-29 Coors Porcelain Co Improvements in or relating to a method for manufacturing articles from compactable materials
GB1109725A (en) * 1965-05-14 1968-04-10 Aug Gundlach G M B H Method and apparatus for producing shaped members from a mouldable refractory material
GB1165384A (en) * 1966-09-03 1969-09-24 Willan Ltd G L Improvements in or relating to Refractory Articles
GB1180298A (en) * 1967-09-11 1970-02-04 Peter Frank Rossmann Improvements in or relating to Apparatus and Method for Pressurizing Materials
GB1265993A (en) * 1969-01-27 1972-03-08
GB1300864A (en) * 1969-03-03 1972-12-20 Asea Ab Method of sintering powder bodies
GB1321451A (en) * 1970-01-15 1973-06-27 Foseco Int Production of refractory articles
GB1339483A (en) * 1970-09-07 1973-12-05 Miki M Method for producing liners for feeder heads used in metal casting and an apparatus therefore
GB1387415A (en) * 1971-07-28 1975-03-19 Lucas Industries Ltd Method of and apparatus for producing a hot pressed component
GB1449349A (en) * 1973-06-25 1976-09-15 Nat Forge Co Mould apparatus for isostatic pressing of hollow parts

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ENCYCLOPEDIA OF CHEMICAL TECHNOLOGY KIRK - OTHMER VOL 3, PAGES 521-590 RE CERAMIC INDUSTRIES *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0846514A1 (en) * 1996-12-05 1998-06-10 Akechi Ceramics Kabushiki Kaisha A continuous casting nozzle for casting molten steel
EP1097763A1 (en) * 1999-04-05 2001-05-09 Akechi Ceramics Kabushiki Kaisha Continuous casting nozzle
EP1097763A4 (en) * 1999-04-05 2001-11-14 Akechi Ceramics Kk Continuous casting nozzle
EP1101549A1 (en) * 1999-04-09 2001-05-23 Akechi Ceramics Kabushiki Kaisha Continuous casting nozzle
EP1101549A4 (en) * 1999-04-09 2001-11-14 Akechi Ceramics Kk Continuous casting nozzle

Also Published As

Publication number Publication date
GB2202218B (en) 1991-02-06
GB8803809D0 (en) 1988-03-16

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PCNP Patent ceased through non-payment of renewal fee

Effective date: 19930218