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* .LETIN ASBESTOS BULLETIN Vol.5. I No.2 March - April, 1964. Editor: C. Z. Carroll-Porceynski CONTENTS Page. Part 1. ASBESTOS MINING....................................................................... 27 Part 2. ASBESTOS CEMENT(commencing Item 119) . . 32 i Part 3- ASBESTOS TEXTILES ............................................................. 41 Part 4. FRICTION MATERIALS ............................................................. 42 Part 5. REINFORCED PLASTICS ........................................................ 43 i 1 Part 6. ASBESTOS JOINTING, COATING ETC................................. 44 i Part 7. PLASTIC BUILDING MATERIALS AND PIPES . . . . 45 Part 8. ASBESTOS PAPER & INSULATING MATERIALS . . . 47 Part 9. REFRACTORY FIBRES ............................................................. 48 Part 10. MISCELLANEOUS ....................................................................... 50 Part REVIEW OF JOURNALS ............................................................. 51 1--l i--1 (C) Copyright Astex Publishing Co., 1964. 1 ASARCO ALV 0007225 ASBESTOS BU: L~Tj.H ?apt 1. A2BBSIQS IQ KING. Lvs HCBUCTIOIv OF ASBESTOS 3Y COUNTRIES I!' o :j C:untry rth America: ana da . S. A. T^ial 1959 952,928 41.239 994,167 I960 1961 1,014,641 1,064,753 41.025_________ 47,912 1,055,666 1,112,665 27 TRIG TONS. 1962 1,109,943 48,253 1,158,196 - m>.i j; in ; utk America: r6T. T i r.a c 2i vi^ r-n ^ ~ ** 290 152 11,181 4,622 16,245 300* 300* 300* 60 52 51 13,236 16,950* 17,000* 3,931_____________ 590_____________ - 17,527 17,900* 17,350* -`arc res Au~-mriu Bulrari a Fir.lrir.a Fras.ce u*. u rc,i - Formoral 3;: air U. S . S. R. * - Vi 0. Fatal* 1,000 8,690 21,192 45,158 36 17 545,000 4,307 630,000 195 1,100 9,556 26,002 51,412 131 4 600,000 5.416 690,000 512 1,100 9,379 27,892 56,986 19 10 800,000 6.086 900,000 456 1,000* 9,860 25,000 55,550 -- 1,000,000 6,714 1,100,000 Asia: China* Cy.ru s India Japan -'-crea Fnili r.rines Taiwan Turkey Total 80,000 13,085 1,328 12,368 80 51 136 373 107,000 80,000 21,152 1,711 15,460 671 33 440 216 120,000 80,000 14,703 1,468 17,054 309 75 40 450 114,000 80,000 18,137 1,547 14,107 1,209 941 476 643 117,000 continued next page. ASARCO ALV 0007226 * 28 Country Bechuar. aland Kenya Morocco Mozambique " S. Ri.rdr si a 'S.Africa Swaziland U.A.R.(Egypt Hegion) _L U -- 1959 1,279 39 24 108,589 165,474 22,504 455 296,374 I960 1,163 106 20 121,529 159,542 29,054 45c `11,855 ASBESTOS BULLETIN 1961 1962 1,745 137 2,155 140* 147 146.509 176,750 27,934 100 128,997 200,761 29,783 2 30 253,552 230* 362,166 ^ o " r i s. t A un Trail a New Zealand Total 16,216 581 16,797 Vt r11 Iri' ai 2.060,COC 14,164 289 14,453 2,210.000 15,192 338 15,530 2,520.COO * Estimate - ~ ^ v*/-v U.S.Bureau of Mines, 10ay 27, 1963. 16,685 17,025 2,770,COO SOUTH AFRICA. IOinc-ral Trade Notes No. 6, i_yqCOi , np in Level opments in the asbestos industry in the Republic cf Sc uth A.frica during 1962 included the following: 103 A nev; 1,356-foot shaft was surd: at the .tenge mine of Rgnop (Fty.) Ltd., the only amosite producer in the Republic, -reduction was expected to increase to 90,000 tons in 1963* 104 ICsauli Asbestos Mining & Exploration Co.Ltd. , the largest chrysotile producer, lowered prices in October and ended the year with an unsold stockpile at its mine on the Swaziland border. Barberton Chrysotile Asbestos Ltd., the second largest producer, suspended operations at the end of the year because of market con ditions. African Asbestos Cement Ccrp.Ltd., modified its plant at the Kalkkloof chrysotile mine to produce a higher grade and cleaner product to meet buyers' requirements. The mine, capable of expansion, was to be kept at the 4,000-ton-per-year level until market conditions improved. ASARCO ALV 0007227 30 ASBESTOS BULLETIN U.S.S.R. 111 PHYSICO-CHEMICAL INVESTIGATIONS OF ASBESTOS FROM VARIOUS EEFOSITS. N. I. Toker, L. K. Abend and E. P. Kraineva. Nauchn.tr.Vses. n.-i. in-t.asbest. orom-sti, IS62, Typo, 62-103; Ref. Zhur.Khim., 1963, 23K247. K-: thcd? of the X-ray, chemical and thermal analyses of asbestos fibres are outlined. Results are given of the investigations of asb-:st',3 fibres of various origin carried out by the Institute NIIAsbcst. These data can be utilised for the evaluation of asbestos from newly discovered deposits. AUSTRALIA. 112 THE MINERALOGY AND PARAGEHESIS OF THE CP.OCIDOLITE VEINS AT V.UTTEKCOI.I GORGE, V.'.A. N. A- Trueman, Proc.Aust.Inst. Min. Metall. No.205, Melbourne, June 1963, pp.113-121. The relationship between the parager.esis and the loss of fibres during processing is discussed. The presence of magnetite in acte~r|~~ veins prevents complete fiberisaticn. There is a marked similarity between the veins described and those in the >'gn?-V,'osterberg area of South Africa. GREECE. 113 GREEK ASBESTOS. Mining Journal, London, February 1964, No.6713, p.103. The American Climax group is reported by "Hellenews" to be interect-d in the ?Iczar.a Asbestos field, which is controlled, through kero-os* os S.A. by the U.S. Kennecott Corn. A representative cf American Climax has been collecting information on the asbestos dope sit in Greece. The deadline for the investment by Kennecott in the Kozani asbestos deposit expired on December 31 last, and Kennecott's intentions regarding their investment the future cf the concession agreement with the State are not disclosed. Under the agreement Kennecott had the right to exploit these asbestos deposits until their depletion. An investment of $14 million had been approved under the law for the protection of foreign investments for exploiting this deposit, and setting up an asbestos processing plant. The initial agreement was signed in 1956,and extensions have since been granted. The Company has purchased the area, and carried out a survey cf the extent and grade cf the deposits which has so far absorbed a total of about $1 million but no further plans have been announced. ASARCO ALV 0007229 asbestos bulletin YUGOSLAVIA. 31 114 THE PROCESSING AND UTILIZATION OF ASBESTOS FROM THE STRAGARI DEPOSITS, YUGOSLAVIA. M. Ferjan. Rud.C-lasnik, 1962, No.2, 28-35; Ref.Zhur.Khin., 1964, 1 M249* A '.vet process was applied for dressing chrysctile asbestos from Sorurari deposits, which occurs in the form of strongly interwoven fibrous aggregates. Enriched asbestos was first kept for two weeks ir. a concentrated MgSO^ solution. Then the softened r.sbestcs was subjected to the action of a turbulent stream of water with the introduction of air, followed by a mild defiberatior. process (by mutual friction). The process yields undamaged asbestos fibres suitable for various industrial applications. OTHER NBA'S. JArANESE FATiiNT 20632/63* PROCESS FOR REFINING CRUDE ASBESTOS. K. A. Oestcrheld. A suspension of crude asbestos in a liquid is forced along spirral curves and introduced under pressure between friction surfaces. The fibres are subjected to kneading and bending action in altern ative directions. 116 SOUTH AFRICAN PATENT 63/2587. AUTOMATIC MIXING OF ASBESTOS FIBRES. Amiantifera di Balangero S.p.A. This process comprises subdividing a constant volume of asbestos fibre mixture in two portions which are weighed on a scale having different arms with additional weight. --7 SUBSTITUTE FOR ASBESTOS? The Financial Times, Feb.7, 1964, p.ll. synthetic Fibres which may substitute for asbestos have been produced economically by researchers of the U.S.Bureau of Mines, rr.teri or Department Building, Washington 25, D.C. The silicon carbide fibres are made by decomposing natural silicates to produce green and white threads up to 1.5 millimetres long. They will resist oxidation it is stated at up to 930 degrees Fahrenheit m air. H8 SAFETY AND HEALTH REGULATIONS FOR ASBESTOS PREPARATION PLANTS. U.S.S.R. Gosudarstvennyi komitet po delam stroitel^stva. Moscow, Gosstroiizdat, 1963, 36p. Monthly index of Russian A.ccessions. Dept. 1963, 16, No.6, 1584. ~ ASARCO ALV 0007230 32 ASBESTOS BULLETIN 119 THE EFFECT OF THE ADDITION OF GYPSUM TO CEMENT IN THE FROST-RESISTANCE OF ASBESTOS CEMENT. T. M. Slavina, G. S. Blokh and P. N. Sokolov. Tr.N.-i asbesta, slyudy, asbstsement. izdelii i pmektir. str-va predpriyatii slyud. nrom-sti, 1963, No.16, 145-155; Ref. Zhur.Khim. , 1963, 2314225 Tie loss Ir. strength, ultimate deformation (in thickness) and char.res ir. external appearance were determined for asbestos cement ?-amr.Ies, with or without gypsum, upon subjecting them to 50 and 75 freezing-thawing cycles during 28 days. It has been found that the addition of gypsum improves the frost-resistance of asbestos cement, especially when it contains a high-alumina cement. The '-rtimum. amount of gypsum depends or. and increases with the C3A. content of the clinker and the dispersibility of the cement.^ How ever, wper. the specific surface of a high-alumina cement exceeds -Cl.' enVg, even the addition of gypsum cannot prevent some decrease in the frost-resistance of the asbestos cement products. INVESTIGATIONS OK THE EEFCRM-.TION OF ASBESTOS CE.IENT ON HARDENING UNDER VARIOUS MOISTURE CONDITIONS. T. M. Berko vich, N. G. Makeeva c R. V. Medvedeva. xr.H.-I. Inst, asbesta, slyudy, asbestc-tcem.izd. i proektir. str-va credorslyud.prem-sti, 1961, No.12, 3-17. Ref.Zh.Khin, 196 3', 2M222. It ha? been found that with the prolongation of air-drying the shrinkage and elongation of asbestos cement tiles are reduced. Ihe deformation of autoclave asbestos cement is much less than that of ordinary asbestos cement. The shrinkage of ordinary asbestos cement increases with increasing CoA content and finer grinding of the cement. In auxeclave asbestos cement the change of the CoA content in the range of 5? tc life does net significantly influence the shrinkage. 121 JAPANESE PATENT 26482/63- COLLARED ASBESTOS CEMENT ?j.rE3. Kipper. Eterrit ripe Co. A collar made of asbestos cement has at one end a recess of a diameter increasing towards the interior of the collar. Ir. order tc join the collar with an asbestos cement pipe, the collar is immersed in water, optionally warmed, to produce swelling, an un hardened pipe is inserted in the collar and pressure is applied from the inside to the pipe end so that its diameter is enlarged and the pipe end, conicaliy expanded, fills the recess in the collar. Then the assembly is cured to produce a collared asbestos cement pipe. ASARCO ALV 0007231 asbestos bulletin 33 THE EFFECT OF THE QUALITY OF RAW MATERIALS OH THE FROSTRESISTANCE OF AUTOCLAVE ASBESTOS CE3SENT. T. M. Berkovich, G. S. Blokh, G. A. Berzemishvili and M. M. Levicheva. Tr. N.-i. asbeota, slyudy, asbestotsementn. izdelii i proektir, str-va predoriyatii slyud. crom-sti, 1963,No.16, 99-107: Ref. Zhur.Khim, 1963, 221:1219. The effect of the quality of asbestos and sand, used in the pro duction of sand cement, on the frost resistance of asbestos cement products has been investigated. It has been found that the frostresistance increases with increasing content of semi-rigid asbestos and is reduced when soft asbestos fibres are used. The frostresistar.ee does not depend on the SiOg content of sand used ir. the production of sand cement. The frost-resistance increases with the increase cf the content of sand grains smaller than 0.1 ram. This car. be ascribed to the formation of a large number cf very small cores in which water does not freeze. 123 AGGREGATE SI.' 89SA IN SERVICE. V. A. Vladimirov. Strcit. Mat. 1964, 10, Ho. 1, p.20. Experience gained with aggregate SM 89&A in the production of asbestos cement sheets is briefly described. Aggregate SK 898A (developed by H. I. nrshov) is an automatic machine for forming corrugated asbestos cement sheets and stacking them. The process is continuous, saves much manual work, and gives better products than conventional machines. RUSSIAN PATENT 155,424. MANUFACTURE OF ASBESTOS CEMENT PRODUCTS. I. I. Bernei. The customary application of high pressures (ICOkg/cm2 cr more) ir. the manufacture of asbestos cement products causes elastic at-format! ens in the sheets resulting in undesirable effects when the pressure is removed. According to the invention, asbestos cement sheets are produced with the use of moderate pressures (of the order of 10 - 15 kg/cm2), which are maintained until the sheets are completely set, i.e. for 3-4 hours. In this way, drastic deformation and the resulting relaxation are eliminated. 125 BRITISH PATENT 946,776. WATERPROOFING ASBESTOS-CEMENT BjA PJ)S U * C. B This patent describes the method of water-proofing asbestos-cement boards (containing free lime) with special silicone emulsion. ASARCO ALV 0007232 34 ASBESTOS BULLETIN 126 FRENCH PATENT 1,346,849- PROCESS FOR HARDENING ASBESTOS CEMENT FIPES. S.A. Eternit. A soft asbestos cement pipe, after removal from the former, is placed inside a rigid tube of a larger diameter and rotated within it during the hardening period in such a way that it turns on the inner wall of the rigid tube and so remains straight. Also the cross-section of the pipe, which is slightly oval after the removal from the former, becomes perfectly circular. 127 FRENCH PATENT 1,337,083. DEFI3ERISATI0N OF ASBESTOS IN A ROD MILL. F. L. Smidth & Co. A/S. Asbestos fibres suitable for the manufacture of asbestos cement are produced by adding 10 - pO of water to crude asbestos and milling the mixture in a continuously operated rod mill. The mill comorisos a cylindrical rotary body filled with loose rods occupying 25 - 45^ of the mill volume. The feed end of the cylinder has one central inlet, while the outlet end is provided with several aper tures . 1?8 SOUTH AFRICAN PATENT 62/1944. MANUFACTURE OF FIBRO-CEMENT ARTICLES. Sirera S.B. Hollow moulding bodies provided with water-permeable walls are introduced into a moulding chamber and the chamber is filled with a mixture of cement, asbestos and water in such a way that the hollow bodies are fully submerged. Pressure is applied to the mixture so that water penetrates into the hollow bodies and is evacuated from them continuously. The bodies are .subjected to oscillations and, optionally, are rotated. Rotational movements may also be imparted to the cement-asbestos-water mixture, if orientation of't'ne fibres in the direction perpendicular to the rotation axis is desire. The chamber is being continuously fed with fresh mixture in order to compensate the volume of the water evacuated. 129 JAPANESE PATENT 23785/63. LAMINATED INSULATION BOARD. Oriental Metal Seize Co. These are prepared by filling up crevices in a porous cemented "excelsior" board with a special insulating composition, pasting up a flexible asbestos board or an asbestos cement plate, using a heat-resistant adhesive, and curing the resulting laminate under pressure of 20-30 kg/cm^. The insulating composition comprises calcined vermiculite, perlite cr asbestos powder, and a polyester or polyvinyl acetate resin. ASARCO ALV 0007233 ASBESTOS BULLETIN 130 PITCH FIBRE PIPES 35 In view of great interest shown in pitch fibre pipes by the asbestos-cement industry and the great potentiality of pipes, the editor of "Asbestos Bulletin" decided tc review this material and its manufacture. It is also interesting to note that cheaper grades of this unique material-asbestos are being added by some manufacturers in their fibre blends, and that pitch covered asbestos-cement fittings are sometimes employed in the applications of pitch fibre pipes. The main advantages claimed for pitch fibre pipes are as follows: lew water absorption, resistance to hot liquids, high crushing strength, good resistance tc parrafin, high beam strength, lightness, flexibility, faster laying with no concreting required, lower laying costs, no wasted pieces, resistance tc corrosion and root renotration. It may come as a big surprise to many users of pitch fibre pipes, who regard them, as a comparatively new material, to learn that their first known use was as long as 157 years age. They wore then, in 1606, carrying water at a monastery at Harder.burg, in Germany. In the 1850s pitch fibre gas mains were laid at Uelser. and were used until 1901, when they were dug up and showed no signs of deterioration. At about the same time - around 1656 pitch fibre water mains were put down in Hamburg; these also were found tc be in a satisfactory condition when uncovered in 1514. 7,'e next hear of pitch fibre pipes across the Atlantic in the Irpls. The main use in the U.S.A. was then fer electrical con duit, the ugh the material was applied in minor degree to other purposes such as gas mains, drains and sewers. The early 1900s saw a great expansion of the electrical industry and from then until the 1930s pitch fibre continued to be used chiefly for electrical purposes. In 1932, a new manufacturing technique was introduced - vacuum: impregnation - which resulted in improved quality and strength. After than, pitch fibre was used increasingly for drain age. Luring the Second '.7 or Id War, other materials in North America were scarce and at a premium. The pitch fibre industry made rapid progress. Meanwhile, in Europe, the United Kingdom had been importing American -and Canadian pitch fibre products since about 1903- After l939i difficulties arose over shipping space and dollar currency with the result that, ten years later, conditions were ripe for the start of manufacture in Britain. In the following decade, ASARCO ALV 0007234- 36 ASBESTOS BULLETIN four firms started making pitch fibre in this country. Within the Inst year, a fifth has'indicated its intention of so doing. British and American producers alike have developed a healthy export business with obvious opportunities in non-producing parts "> "the wcrld. It is unlikely that pitch fibre pipes will again be used for roc- or water mains. However, in drainage and electrical work, the future appears as rosy as ever. In the home market, there are the economic and practical advantages for drainage, coupled with continued large-scale development of the electrical supply industry The same applies in the other economically advanced countries. In the less developed parts of the world, drainage services have still to be provided cr. an enormous scale, while electrical supply must alc~ be expected to make steady progress. Expansion of pitch fibre usage in these circumstances must still be the keynote. ~ 7"* -- /"'T'T'DTT 2 , P Is .*--**. i n ^ -L u xtii* * The schematic layout cf pitch fibre making plant is shown in Pig. 1. K-.-s production of pitch fibre pipes confronts the manufact urers with the same basic problem that has to be faced in most other sections of modern industry: the need for efficient means of quality control. Most products are now customarily made to comply with standards laid down by an independent authority, or t: ccmrly with requirements 3elf-imposed within an industry to secure ar.d retain the confidence of those it serves. Pitch fibre drain and sewer pipes manufactured in the United Kingdom comply with the requirements of B.S.2760 : 1956. Prod uction processes and controls are designed to ensure that the provisions of this British Standard are fully met and that appro priate qualities for other pitch fibre materials are consistently achieved. A short summary of the processes involved - basically the same for all British producers, though differing in points of detail - will serve to indicate what is acne, day in day out, to make certain that the pipe and conduit turned out will withstand all the rigours of its eventual use. Manufacture begins with the preparation of a pulp stock, controlled as to the length of the cellulosefibres and degree of wetness before it is fed to the pipe-forming machine. Where temporary' storage of the stock is involved, provision is madefor continuous agitation to ensure a mix of evenconsistency and character. Since the raw material includes excess runs of news papers and periodicals, refinements such as a magnetic separator ASARCO ALV 0007235 ASBESTOS BULLETIN may be incorporated to remove metal pins and staples. 37 Autenatic ope rati on. A mat of fibre is then picked up on the fine wire mesh of the making drum, excess moisture being removed by vacuum process before the mat is transferred tc the pipe-forming mandrel. The cite is built up continuously, the operation being automatically controlled according tc the time cycles and wall thickness re quired for various diameters. The process is such that the fibres ir. successive laminate are closely bound together to form a homoaeneous pipe, consistent in quality throughout its length and phickne ss. At this stage the "white" pipes are still damp and have to be dried. This is a process comprising three uninterrupted stages carefully adjusted so that the pipes are eventually of the highest possible quality. First of all the moisture is heated but retained within the fibres. Secondly, the heat is gradually increased tc disperse the moisture. Finally, the hot dry pipe is gradually coded. Humidity, heat and air velocity are controlled throughout entirely by instrumentation. Critical Factors. In the impregnation of the pipes with pitch there are three critical factors; the quality and viscosity of the pitch itself, the pressures employed and the time cycles. The coal tar pitch must be refined to eliminate impurities and the specification has beer, improved in recent years tc this end. The degree of vis cosity depends on the maintenance of high temperatures and in fluences the penetration of the pitch throughout the wall thickness of the pipe. Both vacuum and applied pressures are used. The impregnation period varies up to several hours according to the wall thickness of the pipes under treatment, which is also the heading factor in the number of vacuum cycles for any one batch. Subsequent processing is concerned with the machining of pipes to fine tolerances. Similar care is exercised in the Production of the wide range of fitments. The Pitch Fibre pipe making machine manufactured in the United Kingdom has been specially designed for the production of Pipes direct from Wet Stock. .. .The unit develops a new principle in pipe production and iiminates the felt. The prepared stock is fed into a specially ^signed Vat working on pro-flow and overflow, in which is "Solving a 24" diameter Hollow Cylinder Mould. Revolving upon ASARCO ALV 0007236 ju m p i i C> 28 AS3EST0S BULLETIN the- Cylinder I.>uld is an 18" diameter nesh covered Suction Couch Boll end the vacuum. vnluc cf which is approximately 6" of water. The drive car. be either off the Cylinder Mould or off the Couch. The film picked up by the Suction Drum is couched off the f i1'ueh ar.d is in turn transferred to a Hollow Mandrel cf the -appropriate diameter acting -as a Making Hell. The wall thick::-:os is variable, and can be pre-set, warning cf make-up being giver by s signal. Ire:rotated in the design is a "Head Unit" which allows automatic feeding cf the mandrel to the- making position, ar.d Z r\ , _ i :r. after the pipe has been formed. The cylinder mould and the auction couch are hollow and are of latent Geodetic construction. ? ensures perfect rigidity and a constant periphery, and the le unit can produce pipes up to t'C" long. The machine, run as a separate unit, ope rate s on p clc- sed cuit, ana the white water is ret urne a to the st ocV: j. or 5C-. Using 2" diameter as a ba sis x i" v;all the mac nine should AO. c.t the rate cf cnc- per m.i n u "t . This see e d c an be j_yn -- 3' 3 V ith excerience. The pnve r usea is 5 K. P . with a suit- W .- ' , cticn unit. A cc m.rlete plant consists of t he fol low! ng units . {-) Hollander type beater # iU-:/ V ^/ Stuff Chest. Tube terming Machine - 'T'l .nr c; r 1 I" 1 or.g 3 tangov. `~i6' 0" 1 ong C an be sup piied. (h) Aluminium: Mandrels 20OC a r prox. Di ar.e-t 0 Y*S acc erding to pr cduc t i on requi re-ments. (5) Continuous Drying Oven. ( z > Impregnation Tanks. (7) Coal Tar Pitch Tanks. (8) Intermediate Tanks. (9) Cola '.Vater Tank. (10) Lathes for turning pi pcs. (11) Small Drying Oven for ecu rlings Cr. i'equest, the editor of "Asb cstos Bulletin II wo uld be pleased l :.cr.d c>ome further information to all i nterested in th e grent 1iI :ntia!-ity and the production of Pitch Fibre Pi pes. I Ei t li c ~v r.hy i i 1. Extract from, Fitch Fibre Pipe Association, Hews Letter No. 12. 2. Extract from Fitch Fibre Pipe Association, News Letter No.8. 2. Private communication with Knowles Trotman. ASARCO ALV 0007237 ASARCO ALV 0007238 L/VYOvJ T O f PITCH F B R t P tP t'lV M r.O waste paper jtoraqe ___ d J))DM >>'VJM asbestos bulletin PART 3. ASBESTOS TEXTILES. 41 Hi BRITISH PATENT 946,567. PROTECTIVE COVERING MATERIALS FOR PIPES AND BUILDING COMPONENTS. S.A. Prancaise du Fercdo. Tr.e use is made of asbestos fibrous material such as paper, felt or fabric which have outer surface coated with coal pitch contain ing aluminium flakes and the inner with strongly adhesive composit- *71 3ELGIAK PATENT 631,234. VINYL IDE RESIN COMPOSITIONS. General Electric Co., N.Y. Yir.ylhaliie resin-base compositions (preferably PVC) contain curing agents and plasticisers, heat stabilisers (esp.PbCOj) and lubri cants. Curing can be accelerated by heating. The cured composit ions are suitable as electric insulations. Solutions of the resins can be used as binders for heat-resistant fabrics such as glass fibre or asbestos fabrics. U.S. PATENT 3,111,719. FIBRE OPENER AND CLEANER (FOR MINERAL WOOL, ASBESTOS, ETC.) Edison H. Novotny, (tc Jchns-Manville Ccrp.) (Nov.26, 1963). A process and apparatus are claimed for opening, cleaning and felting of fibrous materials to produce a uniform felt having an nx rns.2 2. aminar structure and to reduce the unfiberised particles resent ir. the final material. 131 BRITISH PATENT 946,686. ELECTROLYTIC PRODUCTION OF DIAIKYL MAGNESIUM. K. Ziegler. Ir. carrying this process the anode space from the cathode is separated by e.g. asbestos diaphgrams. '-35 BRITISH PATENT 939,512. 16.1C.63 (26.5.60 GERMANY 26.5.59) METHOD OF PREPARING FIBROUS SHEET MATERIAL. ''.'acker Chemie G.m. b.H. A method is given for the production of sheet material by adding a slurry of asbestos fibres or particles, or the dry asbestos mater ials, to an aqueous disperson of a silicone resin having low emuleifier content and curing catalysts, such as dibutyl tin dilauarate r dibutylin dimaieate. ASARCO ALV 0007239 42 FRICTION MATERIALS. ASBESTOS BULLETIN BRITISH PATENT 920,196- DISC BRAKES. Automotive Products Cc.Ltd. _ z I BRITISH PATENT 927,890. BEARINGS. Ford Motor Cc.Ltd. - - p BRITISH PATENT 932,713- PISC BRAKES. Dunlop Rubber Co.Lt INBCARL PISCS KEEP COOL P FRONT. Machine Design. 19.12.63, p.116. disc brakes fitted tc the Auto-Unions GmbH DK',7 F12 discs mounted inboard along the front axle next to the ial. Disc size- is thereby independent of the road wheel 1C.63-in diameter discs are fitted, which is considerably .ar. would be possible with outboard mounting. An aaditefit is direct cooling of the brake assemblies brought their position directly in the main airflow. The brakes 'actured by Alfred Teves (Germany) under licence from hotograph and diagram. 14 C BRITISH PATENT 931715-% EARING ASSE13LY. Engineering rrcductions (Cleveland) .td. , IC-. L. Donnellan) Priority 14.11.6C. Pub. 17.7.63 specified bearing assembly at least two non-metallic bearing os, e.g. of nylon, polyprcpryler.e, isocyanate condense hi on nets, or material incorporating PIPE fibres are used, A tics sealing ring may also be included. BRITISH PATENT 945911- GRAPHITE FIBRELANE NATES. Ford Motor Co.Ltd. priority 24.4.61(U.S.A.) (Patent- of addition to B.P. 928627) Pub. 8.1.64. A laminated structure includes layers of graphite fibre adhered together with a heat-cured adhesive. It may contain alternate layers of graphite fibre and other material such as glass fibre adhered together. 142 BRITISH PATENT 936,741. PLAIN BEARING. Glacier Metal Co. The bearing (its surface) is made up essentially from a mixture of ar. elastomer, bronze or a sc-lid phosphate, and lead, lead oxide or graphite. A typical mixture consists of 60 vol. silicone rubber, 25 vol. /b polytetrafluoroethylene, 10 vol.fe lead monoxide and 5 vol.Js bronze. ASARCO ALV 0007240 asbestos bulletin 142 HU52IAM PATENT 154,354. I. V. Xragelskii et al. ANTIFRICTION MATERIALS. 43 A white filler is added tc an antifriction material, based on a chenrl-fcrmaldehyde resin and asbestos, in order to reduce the coefficient of friction. A typical composition consists of 40/ cf a rhenrl-fcrmaldehyde resin, 50/- white filler and 10?= asbestos. The material is prepared by mixing together the constituents, cold farming briguettes under a pressure of 300 kg/cm^, and then forming articles fr:n the briguc-ttc-s by applying pressure cf 600 - 1000 Vnt 'cm- at temperatures of from 160 tc 170=C. Alternativelys the articles car. be made by hot-moulding the mixture under pressure. The ere dart oar. be used at pressures up tc 50 - 60 kg/cm.2, and temperatures of 250 to 300C. The coefficient of friction with a me-tal, unier dry conditions, is 0.11, and bc-th surfaces have a long c:rviee life. TART 5- REINFORCE!1 ELASTICS. 144 _ SELECTION OF ELASTIC IT-.TERIALS FOR EXTREME TEMPERATURE ENTIRE INTENTS. elastics Des. Processing, 1963, No.6, rp. 14-19. The methrd by which asbestos reinforced phenolic resin materials are able t: resist very high temperatures as obtained on the sur face cf rockets and missiles is discussed. The ablati ve proper ties of phenolic resins containing a variety of fabric fillers ere compared. The other high temperature plastic materials con sidered include EIRE silicone resins and the newer polybenzimidazolcs. (5 references). 145 FRENCH PATENT 1,346,551. ELECTRICAL INSULATORS. Comp. Franc. Thomson-Houstcn. Asbestos base laminates suitable for electrical insulators are produced by impregnating asbestos sheets with a solution of aluminium monophosphate, drying the impregnated material until it looses tackiness, compressing the dried material to reduce its thickness by 25-45/=, and rolling the compressed material to prepare the lam inate. The products are hard and have good dielectric properties. 146 BRITISH PATENT 945,202. FILLED POLYPROPYLENE. Avisun Corp. Sustained heat resistance is very important in such application as for example in distributor caps under the hood of an automobile, -rcpertics of a crystalline polypropylene--anthophyllite asbestos c~.pcEi-fcian containing 40T= asbestos by weight and superior to same Polypropylene containing no filler. ASARCO ALV 0007241 c+ o ' M 44 ASBESTOS BULLETIN 147 3RITISH PATENT 946,324. FILLED ETHYLENE POLYMERS. The I.lotal Box Co.Ltd. Asbestos nay be used as a filler in such composition developed for adhesive bonding of one metal surface to another. This is eff ected by disposing a composition between the surfaces, heating the metal surfaces and the composition to 160C-200C with cr with out pressure and allowing the metal and composition to cool. 146 FRENCH PATENT 1,338,819- ELEMENTS FORMED BY LIOULBING UNjlER PP.E3SURE. Chr.Lechler t Sohn Nachf. dements having a surface layer different from the bulk of the cdy are produced by placing a layer of the surface material on he" better, of a mould, filling the mould with the bulk material, and applying pressure. The- surface material may comprise impreg nated'paper, glass fibres, asbestos fibres, mineral fibres etc. Suitable resins include synthetic polyamides, polyesters and poly carbonates. 149" GERMAN PATENT 1,161,202. PRODUCTION OF LAMINATES FROM INORGANIC FIBROUS MATERIALS. Westinghouse Electric Corn. Laminate product, suitable for use as parts of aircraft cr guided missiles, e.g. rocket nozzles, are manufactured by a process com prising impregnating several layers of an inorganic fibrous mat erial with an aqueous suspension containing an aluminium compound, phosphoric acid and a solid, inorganic, finely divided filler. The mass is then dried and hardened at an elevated temperature and under pressure. In an example, asbestos paper is impregnated wjth a suspension consisting of 40 parts of an aqueous mixture containing AL(E2P0^)^, 15? H^?207 and 70fo water, and of 60 parts of a finely divided filler (particle size of 75 microns) contain ing equal amounts of silica and aluminium silicate. The impreg- naxed*asbcstcs paper is dried at 100c, wound on a mandrel to form a xube of a desired thickness and hardened bjr heating at 285C for 3 hours. The product can be used, e.g. in a transformer at 500C. PART 6. JOINTING, SEALING & COATING. 150 FRENCH PATENT 1,337,577. SELF-HARDENING, COATING OR SEALING MATERIALS. Chem. Fabrik Grunan. Materials suitable for coating structural materials, or filling-, or scaling hollows, cracks or joints therc-in,are produced frem a mixture of monomeric and polymeric methylmethacrylates, inorganic fillers and known adjuvants. For special purposes,asbestos fibres can be used as a sole filler, or applied in admixture with other fillers. ASARCO ALV 0007242 asbestos bulletin 45 151 SELECT AND APPLY GASKETS EFFECTIVELY. J. J. Whalen. Chem. Eng. (U.S.A.), 1st Oct. 1962, 69, No.20, pp.83-88. The footers affecting the selection and application of gaskets are discussed with emphasis on installation bolt force and seating stress. The minimum gasket seating stress values are given for lead and lead-asbestos. It is concluded that the compatibility cf the- gasket material with the fluid to be sealed must be checked as well as the pressure-temperature limits, the installation belt frree, seating stress andbydrostatic end force. 152 BELGIAN PATENT 634,104 COATING MATERIAL loltofill GmbH. Cearning or filling is made from plaster of Paris (CaSO^, f-B^G) , asbestos (up to 8f=) and a mixture of methylcellulose and sodium carboxymethylcellulose as a water-soluble binder (0.07-57) It may also contain a silicone (0.04 - 1>). The grain size of plaster of paris should be below 0.2 mm; preferably 70-80?o should pass a C.05 mm. sieve and nothing is held on a 0.10 mm. sieve. The plaster should have a setting time of at least 15 (measured according to DIN 1168-2.62 with a mixture of 65 parts of water ar.d 100 parts of plaster). 153 GSH.iAN PATENT 1,1,159,712. HOLLOW PACKING RING OF AN ELASTIC MATERIAL. Kupfer - A.sbest - Co. Gustav Bach. The cavity of the ring is divided into at least two compartments, ere of which is filled with a gas to increase the elasticity of the ring, whereas another compartment is filled with a heat-con ducting liquid to ensure good heat conductance. The ring is hade from rubber or an elastomer, e.g. neoprene, fluon, or a silicone elastomer. The material can be reinforced with glass fibres, asbestos fibres, flaked asbestos or the like. ART 7. BUILDING MATERIALS & PLASTIC PIPES. '-54 BIGGEST USE OF PVC PIPE IN WATER CHLORINATION. Rubber and Plastics Weekly, 1963, 144, No.24, 864, 886. Over 7000 ft. of rigid unplasticised PVC pipe, up to 12 in.size, Eas been used in what is claimed to be the most extensive chlor ination scheme in Britain to employ this type of pipe. The insul ation is to protect the swimmer at London's Lido from health hazards cf water pollution. The method adopted to lay the piping is briefly explained and illustrated. ASARCO ALV 0007243 K 4g ASBESTOS BULLETIN 155 ELASTIC PIPES: THEIR CONSTRUCTION & USE. D. Strachan (Bristol Aeroplane Plastics Ltd.) Resin News, _3, 9 Sect.1963, pp.7-9. A detailed account of the construction ana uses of epoxy resin filament wound pipes is followed by a brief cor.parison of other elastic pipes. i table, 4 figures. 15f PLASTICS IN BUILDINGSt PRESENT & FUTURE APPLICATIONS. B. Brown (llcnsanto Chemicals Ltd.) raint Journal, 16, 125, January 1964, pp. 647-649* (Lecture given recently iirmincnam wsuiidrnc The erormruios of the elastics materials chiefly used in building arrlicatims are described, and the range of these applications is surveyed. Future possibilities, including the increasing use of reinforced plastics for certain types of buildings, are discussed. 15" BUILDING EXHIBITION REPORT. British Plastics, j*6, L2 December 1963, pp.662-667 (See also Plastics, 28, 314, December 1953, pp.57-58* 61). A variety of recent building applications of plastics are featured. 21 r.hrt: craohs. -t-c JAPAN? SE PATENT 23786/63- LIC-HT-'.VEIGHT GYPSUK BOARD. i eye ICoatsu Inds. Inc. slurry is prepared from calcined gypsum and an aqueous urea-aldehyde- resin solution, with the addition of a surface-active arena and, optionally, an insoluble light-weight filler, such as saw oust or perlate, or reinforcing agent such as glass fibre, rock wool, asbestos fibre and the like. The slurry is foamed by bubbling through it an inert gas, such as air. The foamed slurry is moulded between two sheets cf paper board. The resulting light-weight gypsum board has a density of from 0.4 to 0.8, and is useful as a structural material having excellent properties, especially heat resistance. 159 BRITISH PATENT 94 3,158. IUPROVELIENTS IN FLOORING. The Rubberoid Cc. Asbestos based grease resistant flooring is covered by this patent. 160 PLASTIC PIPING. Intern. Pipes & Pipelines. Jannary 19 64, p. 4 2. Progress review includes corrugated FVC pipe for land drainage. ASARCO ALV 0007244 ASBESTOS BULLETIN 161 FRENCH PATENT 1,347,401. Chen. Works. VINYL RESIN TILES. Carlisle 47 Floor tiles are produced from; (a) a vinyl chloride-base resin containing at least 80f; of polymeric vinyl chloride, the rest being an cthyler.ically unsaturated organic compound capable of copolymer- ising with vinyl chloride: (b) asbestos and (c) a discolouration stabiliser, for instance a compound having the general formula X (NH)CK(r1)r2 are hydrogen, alkyl or aryl). 162 GLASS-FIBRE REINFORCED PLASTIC PIPE. Chen. Eng. 1962, No.17, p.160, and No.18, p.18. The production and uses of glass fibre reinforced plastic piping are discussed. PART 8. ASBESTOS PAPER & INSULATING MATERIALS. 163 JAPANESE PATENT 25158. PAPER. Shimure Nickel Mfg.Cc. Asbestos having a high magnesia content is used as a basic material to an additive in the manufacture of asbestos-containing paper. Suitable asbestos has the following composition: SiO? 40^, CaO below 255*, Alo03below 15^, FeO or FepOl below 8?;, MgC above 13/;. . .The ratio (SiOp + AI2O3): (CaO + MgO + FeO) should be from 0.7 to 11 164 BRITISH PATENT 949,329. THERMAL INSULATION FOR PIPES. 3ell's Asbestos & Eng. Ltd. 165 FRENCH PATENT 1,346,499- INSULATING MATERIALS. General Tire & Rubber Co. Heat insulating material consists of a vulcanisable elastomer con taining asbestos fibre of such dimensions that it is retained on Tyler screen No. 325 (0.044mm.apertures); 3-200 weight parts of asbestos fibres are used 100 weight parts of the elastomer. 166 U.S.PATENT 3,037,895. REINFORCED PIPE LINE FELT. Johns-Manvilie Corporation. In the manufacture of a reinforced pipe line felt having one or more elongated longitudinal edges, several asbestos papers are -air.inated, and a number of glass strands are embedded between adjacent inner papers so that the glass strands are paralled to the longitudinal edges. j ASARCO ALV 0007245 ASBESTOS BULLETIN 157 JAPANESE PATENT 7/63. PREVENTION OF THE OXIDATION OF CARBON ANODE IN THE ELECTROLYTIC PRODUCTION OF MAGNESIUM. Sunitamo Cheia Co. Ir. or der to prevent oxidation, carbon anode above the level of olxen salt is covered with a protective pipe made of a heat- resi: tant and chlorine-resistant material, such as china clay, pace between the carbon anode and the clay pipe is filled wi tr. materials which also are resistant to heat and the action of ch I^rir.e, e.g. a carbon paste or a mixture of asbestos powder and V.p ic; glass. The top of the pipe is covered with coal tar pitch " -T". si liccne oil, and the foot of the pipe is sealed with asbestos cl th , cowdered Na Cl or KC1. GEEIAN PATENT 1,159,340. HEAT INSULATING MATERIAL. Philip Carey Mfg. Co. Heat-insulating material, which is formed by pressing and has the ability to retain its form, consists of 45 - 94 weight of ex panded perlite, 5 - 20fc of a mcnxmcrillcnite clay (e.g. bentonite) as-a primary binding agent, 1 - 20 of an organic material as a secondary binding agent, and up to 15?= of a fibrous material. The organic secondary binder must be resistant to boiling water (this property can be imparted by the addition of 0.2 to 1 wt. ^ of a silicone). The product has good mechanical strength, high heat-insulating properties in xhe temperature range of from - 212 to + 927C, and is resistant to the attack by moisture or boiling PART 9. REFRACTORY FIBRES. 169 ZIRCONIA FI3RES. Plastics Des. Processing 1963, No.4, p.36. The development of zirconia fibres as a high temperature reinforce ment for plastic materials is considered briefly and some propert ies of p,her,olic resins containing these fibres are given. 170 FRENCH PATENT 1,344,836. MULTI-COMPONENT CONTINUOUS FIBRES. Owens-Corning Fiberglass Corp. Composite fibres are manufactured by heating a mineral material to the softening point, flowing the stream of this material in the form of a cone, introducing a metallic body into the cone and heating it to the softening point and drawing the two materials tc form a composite filament in which the metal forms a continuous core. ASARCO ALV 0007246 50 ASBESTOS BULLETIN 177 JETAL FIBRE CONTACTS RESIST ARC EROSION. The Financial Times, February 5, 1964. High-current electrical contacts made by commonly used powder metallurgy techniques often show severe metal losses through arc erosion. Work done by two U.S. scientists, C. Deibel and J.Evanicsk.o, new of Advanced Concepts Inc., Jeanette, Pennsylvania, U.S., shows that if the contacts are made of fine refractory metal (tungsten) fibres embedded in a highly conductive metal such as copper or silver, arcing resistance is significantly superior. PART 10. MISCELLANEOUS. 178 BRITISH PATENT 945,512; 945,513. FILTER I,lATSRIAL. Comp, de Saint-Gobain. Filters for hot industrial gases are made by dispersing cellulose, glass fibres and asbestos in an aqueous solution of sodium sili cate so that the cellulcsic swelled by the latter, and by adding calcium chloride to the dispersion to precipitate calcium silicate and"treating the suspended mass to obtain the filter material in sheet form. The normal paper manufacturing techniques are applied. 179 FRENCH PATENT OF ADD!!. NO. 80,601 (TO NO. 1,326,302) II..rBGVEIuENTS IN FILTER IiiATERIALS. Etat Francais. Filter materials containing a mixture of glass fibres and asbestos fibres bound by means of neoprene or polyvinyl acetate is prepared in a alkaline medium. In an example, an aqueous slurry contain ing glass asbestos - and, rilsan fibres is made alkaline (pH 6.5 - 9)hy_the addition of caustic soda, a neoprene latex is added to the slurry and neoprene is precipitated onto the fibres by the addition of aluminium sulphate. 18C GERMAN PATENT 1,157,201. PROCESS FOR THE PREPARATION OF A FILTER LAYER. Seitz-Asbest-Werke Theo & Ceo Seite. The preerroti-n of a filter material layer by the settlement of a mixture of organic and inorganic fibres (natural or synthetic), having a diameter of 10 microns or less, from a liquid medium com prises rolling the upper surface of the layer, during the wet stage of the process, using rollers provided with ribs or other protrus ions. The rolling results in the densification and consolidation of the filter layer, the orientation of the fibres, and the in crease of the surface area. ASARCO ALV 0007247 AS3EST0S BULLETIN 51 181 FRENCH PATENT 1,337,606. LUBRICATING COMPOSITIONS. Montecatini. Lubricating compositions which may be applied on metallic surfaces wetted or coated with a phosphate or oxalate, or pretreated in a bath containing, for instance, NaCl, lime, borax, sodium sili cate etc., comprise a mixture of polyethyleno-polyprcprylene glycols ar.d an inorganic compound, e.g. asbestine. 182 FRENCH PATENT OF ADDITION 814^8 (TO No.1,304,683) DEHYDRATING ELEMENT. Dydra S.A.R.L. A dehydrating element is described comprising an absorbing sub stance reinforced with a fibrous material, such as paperboard, paper, asbestos or rock wool. The diagram of the apparatus is shown. 183 CHRYCOTILE FIBRES - FILLED OR HOLLOW TU3ES. Chem.Eng.Hews. Sept. 30, 1963, 1, No.39, pp.34-35. The- controversy is reviewed and the latest work by Dr. E. J. W. Whittaker is reported. He presented his mathematical interpret ation of the results to the Vlt'n Congress of the International Union Crystallography in Rome recently. FART 11. REVIEW OF JOURNALS. "ASBESTOS", January 1964. 807 Western Saving Fund Bldg., Philadelphia 7, Pa*, U.-'.A. 134 GREETINGS, page 2. 165 K. J. MESSEL, Election as President of Lake Asbestos of Quebec, page 16. 186 VICISSITUDES IN ASBESTOS MARKETS, page 16. 187 PROPOSED ASSOCIATION CLASSIFICATION OF CAPE BLUE ASBESTOS, page 28. . 188 AUTOMOBILE SALES, page 32. 189 MARKET CONDITIONS, page 34. 190 PRODUCTION, page 40. 191 IMPORTS & EXPORTS, page 42. 192 INDUSTRY NEWS, page 44. 193 CURRENT RANGE OF PRICE, page 52. 194 ASBESTOS STOCK QUOTATIONS, page 54. 195 ASBESTOS PATENTS, page 56. This item covers four patents related to Treatment of Asbestos, Sealing Composition, Coating Composition and Asbestos Paper Manufacture. 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