Document qdJykQE7pQzb4ERQR6mv9gK35

FILE NAME Fibreboard FIB DATE 1984 Mar 1 DOC FIB021 DOCUMENT DESCRIPTION Stephen Berger's Review of Rubin Lewon's Journal's and Records REVIEW OF RUBIN LEWON'S JOURNALS AND RECORDS by Stephen L. Berger March 1 1984 Rubin Lewon kept several journals along with various correspondence and notes during his employment as a research engineer for Plant Rubber & Asbestos Works now Fibreboard Some of the notebooks and portions of the journals deal with material such as plastics and electronics not related to insulation and will not be discussed in this report The general impression of Rubin Lewon through reading of the journals is one of a competent conscientious engineer concerned with both the daily operation of the plant and with research projects The first of the journals was presumably begun when Lewon first started to work for Plant Rubber & Asbestos He meticulously went through Chemical Abstracts taking notes on various kinds of thermal insulations under the following headings Insulation Insulators Magnesium Carbonate Magnesite Dolomite - Grabertite Kieselguhr Diatomaceous Earth Vermiculite Calcium Silicate Ammonium Carbonate and Ammonium Magnesium Carbonate These notes were mainly on abstracted patents The first journal covered from about 1907 to 1932 the years refer to Chemical Abstracts The following are brief descriptions of the entries in which insulations that did not necessarily use asbestos are mentioned Page 3 U.S. Patent 1,000,295 1911 Insulation for boilers and steam Page 4 Page 11 pipes - 65 lime putty 30 sawdust and % plastering hair British Patent 13,248 1912 Insulation - 75 diatomite 12.5 lime 12.5 asbestos and water Asbestos is optional or may be replaced by other fibers U.S. Patent 1,228,609 1916 Insulation - magnesium carbonate precipitated upon asbestos or coconut fibers Page 13 Pages 28 29 U.S. Patent 1,279,975 1918 Insulation - magnesia diatomaceous earth and fibrous material U.S. Patents 1,520,893 1,544,196 and 1,544,215 all issued to Celite later bought by Manville and deal with calcium silicate insulation which can be reinforced with a variety of fibers Page 32 U.S. Patent 1,569,755 1926 Diatomaceous earth lime fiber and -3- water U.S. Patent 1,590,132 1926 Diatomaceous earth lime fiber and water Page 39 Page 45 Page 59 Page Page Page Page 64 Both patents issued to Celite U.S. Patent 1,613,137 1927 Asbestos or other fibers diatomaceous earth bentonite and boiling water U.S. Patent 1,715,977 1929 Insulation of vermiculite diatomaceous earth and binder U.S. Patent 1,811,516 1931 Diatomaceous earth calcium carbonate and basic magnesium carbonate German Patent 535,244 1927 Basic magnesium carbonate with or without fibers The second journal continued with these notes from Chemical Abstracts Page 1 British Patent 477,763 1/3/1938 An insulation that can contain asbestos mineral or slag wool cellulose or wood fibers Page 5 U.S. Patent 2,130,091 1938 Issued to Picher An insulation Page 13 containing vermiculite asbestos and magnesium oxysulphate U.S. Patent 2,168,288 1939 U.S. Patent 2,168,289 1939 Both issued to Philip Carey Sheet insulation containing a bituminous and fibrous mixture Fage 15 U.S. Patent 2,175,715 1940 Issued to F.E. Schundler later bought by Manville Vermiculite insulation The third journal was a log of the plant from January 1 1939 to August 1941. There are two entries of interest Page 6 Dust bad when new C - block machines running Suction measured 4 but 5 / mill blew considerable dust to canvassing dept which caused inconvenience C presumably stands for pipe covering Entry of February 9 1939 mentioned discussion between Rubin and SAA presumably S.A. Abrahams about the validity of a patent which might be issued to Plant Rubber & Asbestos Works and would be directed to -5- circular molding A previous German patent describes this circular molding idea and the setting of normal carbonate trihydrate Lewon kept a separate file on patent matters Two letters both written by Iewon in this file dealt with the infringement of patents A letter to Dr. A.M. Erskine dated January 29 1947 discussed the Manville process for making precision molded 85 magnesia blocks and whether there was a question of infringement of Plant's patents He recommends that the question of infringement be put aside for awhile Lewon indicated that Flant's patent position was extremely weak Steps in Plant's patented process such as the step of preheating were previously described in German patents and articles Therefore some of Plant's patents might have been invalid and unenforceable A memorandum dated March 7 1947 discussed U.S. Patent 2,413,958 issued to Manville on January 7 1947. Lewon concluded that at least part of the process in this patent did infringe on Plant's patent 2,209,754 Lewon also commented that the insulation block made by Manville is superior to that made by Flant Lewon further questions whether a pipe covering can be made by this method because it would have to be made in sections which might warp and distort The following are miscellaneous letters proposals and memorandums found in lewon's records A Proposed Research Program dated August 27 1942 mentioned on page 2 that there was a possibility of developing a high temperature heat insulation cement without the use of fiber A Research and Development Program for low pressure insulation was written by A.M. Dinkfeld to S.A. Abrahams and dated January 12 year unknown but probably 1944 or 1945 The object of this program was to produce a precision molded 85 magnesia pipe covering having a temperature limit of 300 A cheaper 85 magnesia pipe covering would be produced but would not be substitutable for the regular 85 magnesia because of the temperature limitation On page 2 the letter states This might be done through the use of a vegetable fibre in place of asbestos or through a blend of vegetable fibre and asbestos in sufficient proportions to cause the destruction of the product at say 300 However work done with vegetable fibres for this purpose does not look too promising since the fibre can be destroyed by heat without the total destruction of the insulation It seems that it was surprising that vegetable fibers could be used at a higher than 300 temperature The explanation is that even if some of the vegetable fibers were destroyed in the space near the pipe the integrity of the pipe insulation as a whole would be -7- preserved It is suggested on page 3 that a blend of alpha cellulose and redwood bark fiber might work to produce the cheaper product A progress report entitled Asbestos Cement Products III covering the period October 8 1946 to December 10 1946 and written by G.M. Nummy investigated the use of fibers other than asbestos in products such as shingles On page 3 it states organic fibers such as Asplund wood fibers might be used satisfactorily Further research is recommended on various fibers and fiber substitutes A memorandum dated March 31 1947 and written by Lewon discussed a report by the British Army on the German Asbestos Industry The German asbestos manufacturers substituted cellulose wood fiber for asbestos in 1942. The product was claimed to be satisfactory However all of the manufacturers stated that they prefer and would again use asbestos in their product when it becomes available again In conclusion it can be said that Lewon and others at Plant Rubber & Asbestos Works knew thermal insulations could be made without asbestos and that 85 magnesia might have been made without asbestos The reports taken as a whole suggest that economic considerations inexpensive asbestos were foremost in the minds of the research staff of Plant Also there was mention of the considerable dust created by the machinery