Document 5by6Npo17wVp1p24kYeLmaxDV

FQSECO, EMC. INTER-COMPANY AND INTER-DEPARTMENTAL CORRESPONDENCE \ y t: H. D. Shcpliard i FROM: A. G. Santlghlan DATE: January 29, 1973 SUBJECT: Starring from January 5, 1973, our staff has developed anew recipe trying to substitute asbescos in Profax type material. Our main intention was and is still being to develop only one recipe asbestos-free covering the necessities of all types of machines. The main raw material used to substitute asbestos is Wollastonlte (fiber type) which has the following principal characteristics: 1. Chemical composition --- S102 CaO FeO ai2o3 MnO MgO T102 L.O.I. 50.90X 46.90* .55* .25* .10* .10* .05* .90* 2. The mlneralogieal composition, calculated from the above chemical composition and it could be: CaO S102 (Wollastonlte) - 2FeO S102 (Falalite) - A1203 Si02 (Sllllmanlte) - MgO S102(Enstaclte) - MnO S102 (Rodonite) - T102 S102 98.2* .7x 0.41* 0.35* 0.19Z 0.009Z 3. The melting point for pure Wollastonlte is 1540*0. The melting point for the used Wollastonlte is 1300-1330*0 because of the Fondite mineral. 4. The density of the Wollastonlte is 2.9 ) 2- - The durity (Mohs ")4.5. The recipe cried in the Lab vas Silica Flour Dyacomite Resin Resin Fiber glass Wollastonite Bentonite 61.7 2.8 3.0 1.0 .5 29.9 1.0 .1 The solid concent cried in Che slurry vas 20Z, 25Z and 30Z. The best results were obtained ac 30Z solid concenc. The flowability is better than Profax 31 which has a solid content between 13 and 18Z. The Araitec tests showed a better curve than Profax 31. The final value for the new recipe is 7000 - 7500 Btu/ft^ versus 7500-8000 Btu/ft^ for Profax 31. The final race of heat loss is 60-90. Btu/ft^ min. versus 90-100 Btu/ft^ min. The above recipe vas tried on SAM on Jan. 11, 1973. The slurry worked as follows: 1. The solid content 30Z. 2. The tool filling 4-5 seconds, almost even. 3. After 20 cycles without any cleaning of cool or screens, the slurry continued to form corner posts at the correct thickness with no harmful material buildup. The machine had the following characteristics: 1. Head pressure for forming: 50 constant during the experiment. 2. Head pressure for dewater: 50-32. 3. Pressure to head: 60. When the holding tank vas 1/4 full the slurry was thinned to 20Z solid content. There vas no indication of the suspension system failing. The physical properties of the comer posts obtained were: 1. Density: 0.853 - 0.900 2. Trans. Strength; 293 - 432. On January 17, 1973 vas cried a plant run with the recipe on K-3 (Mark III) machine. The tools used on this experiment were 494C boards and 490 end pieces. The 494 tool was cried with a spacer (thetool was set up for Profax 31). During the tool change (494 to 490) the spacer was eliminated. The solid content of che slurry was 30Z. Both tools worked well. 1436 -3- Tho principal characteristics were: 12.5 sec. filling time. 25.0 sec. forming and dewater time. Static pressure: 60 Dynamic pressure: 40 Circle time: 79.5 sec. Green strength: very good. The material was not cured well because the right oven was not used. The moisture content on green state 32-35%. The Amitcc tests showed 7400 Btu/ft^ and final rate, was 99 Btu/ft^ min. The density: 0.750; the transverse strength: 250. On the same day we ran also the K-4 machine using the same recipe for tool #685 ledge boards. The main characteristics were as follows: - a. fill: 11 sec. b. bLowback: 7 sec. c. dewater: 14 sec. d. cycle time: 70 sec. e. static form pressure: 28 f. -- blow back: 25 g. -- dewater: 40 The density of the material was: 0.720. The transverse strength: 220. The Araitec tests showed: 6960 Btu/ft^ and the trial rate was 94 Btu/ft^ min. If the run on K-3 machine was close to an ideal experiment without any major problems testing the high qualities for the new recipe, the run on K-4 machine was less successful because of the holes left at the back of the boards when removing the piece. The opinions are different: 1. A machine problem. 2. A tool problem. 3. An lnadapcable material (recipe) to such tool and machine. My opinion is: This recipe will worl* better if the holding tank of the machine will be properly cleaned and doing a minor change cutting the fiber glass content from .5% to .3%. I am still following the leading idea to gee only one recipe for all types of, machines. On January 22, 1973 we ran B corrugated machine using the Tool #685. The experiment was smooth without any problem. r*37 -4 On January'23, 1973 was scheduled to run one piece hoc cop machine. The experimenc was noc successful. The problem was an unusual screen blockage on Che corners of Che cool. We could noc run che ccsc more Chen 1-1/2 hours getting only 8 pieces with unacceptable defects. The defects were: l1. A thickness variation from che top Co Che bottom. 2. The corners of che piece had less thickness chan Che flat sides. ( The factors which can prove such problems are che following: 1. Bad suspension properties for Che slurry. 2. Long dewacer time. 3. Too much fine particle concent in che slurry. 4. Inadequate vacuum pressure. 5. Previous blockage of che cool. After a careful analysis of che above problems the conclusions are: 1. The suspension properties for che new recipe arebetcer chan che suspension properties for Profax 31. 2. Dewacering time is longer chan Profax 31 but, I consider, is noc che determining one in this case. 3. The finesc particle concent for che new recipe is, after our escimacion, ac lease 15Z less chan Profax 31. 4. The cool was noc cleaned for a very long time. My opinion is: 1. To have che opportunity co run another test using a clean cool indifferent of che.tool dimensions. 2. To make some changes in che recipe. If these changes will be major, purpose co run all tests from che beginning all over. Evidently we already starced Co do minor changes. The pieces obtained from che above experiments are: 1 Pallet of494 1 Pallet of490 CHEAT LAKES l Pallet of685 1 Pallet of690 COPPERUELD 1433 -5Thcse pallets are ready to be shipped to the customers but they need special attention, to follow them through the customer's technological process, to mark down everything indifferent if the man who follows the experiment considers the data useful or not. Also we need a complete report with all the details. I purpose that the experiment in the steel mill plant should be followed by a man from our staff. AS/cel Cc: W. C. Sutherland R. C. Phoenix 1 30