Document 4vN3kbmBGgpojnqQZz4Bvzj1j

FILE NAME Manville JMA DATE 1963-1964 DOC JMA113 DOCUMENT DESCRIPTION Brake Wear Dust - Report & Letters soe JOHNS MANVILLE RESEARCH * AND ENGINEERING CENTER Repo1 Date ... 456 Jamuary 20 1964 Title PETROGRAPHIC AND RAY DIFFRACTION ANALYSES OF BRAKE LINING WRAR DUSTS Requested by W. C. Streib - Request No. 345 c ae AgA o . ce . t SUMMARY Three samples of brake lining wear dust vere examined petrographically to determine whether chrysotile fiber can be distinguished in this type of material Two of the samples were also examined by ray diffraction for confirmation from the following brake linings The samples were 1963 Comet republicaton 12 1963 Pontiac 3 Chevrolet 6 Inlite Lining or Petrographic examination showed the following distrbuion The dust from the Comet lining contained an organic binder plus small percentages of quartz magnetite carbonates talc and rarely & few chrysotile fibers Chrysotile in sizes recognizable under the microscope constituted less than one genral per cent of the total for The dust from the Pontiac lining appeared similar to the one from the Comet lining Not showing the same components in comparable amounts Only an occasional bundle of chrysotile fiber could be detected after prolonged examination of several slides The Chevrolet brake lining dust differs somewhat from the others in that it contains CONFIDETAL possibly 10 per cent quartz Talc appears to be absent appears to be present but was not positively identified of chrysotile fiber was noted as in Samples 1 and 2 A small amount An occasional of graphite mall bundle ray diffraction results JM quartz weak pattern from Comet Lining chrysotile talc fos trace of Dust from Inlite Lining Chevrolet quartz oye mimnoar jor The trace of chrysotile detected by ray diffraction in the Comet lining dust could possibly amount to as much as 5 per cent of the total This would indicate that in addition to the occasional fibers seen microscopically there may be some Notebook No. 2910 p 52 2864 p 88 File 456 PRODUCED | MANVILLE RESEARCH AND ENGINEERING CENTER Repon . 456 Summary Page 2 finely divided and possibly coated fibrils not recognized under the light microscope Failure of ray diffraction to detect any chrysotile in the Chevrolet lining dust sets the chrysotile content of this sample as well below 5 per cent The Pontiac lining sample was not examined by ray diffraction but the incidence of microscopically recognizable chrysotile in this sample is of the same order as in the Comet sample Contents Summary only F. E. Pundsack D. Bailey republicaton McCourty -- ----, ray Diffraction by P. or distrbuion ec K. W. Smith GH --.... Smith . F. Rassweiler CH A. C. Smith 3 genral W. C. Streib for H. G. Koch Not J. P. Library 2 CONFIDETAL JM Se a ee PRODUCED - | Research & Engineering Center Te December 13 1963 8e> One - - ra+ + 2.5 ly fen ayer Brake LinWi earnBug st (es You will recall that during his recent visit to the Research Center Dr. .K W. Smith mentioned a recent theory that asbestos fibers freed in the waring of brake linings might have some pathological effects Mr. Koch attachinga work request cover this bes'obtained bes'obtained war dusts from three cars and I would appreciate your sk " aining these microscopically to see if you can identify sabestos fibers in this material I am TD 345 to La peat also attaching to aZn the pertinent correspondence and would like call 1 your attention to Dr. Smith's request for the material remining after your testay disit disit testay disit a at Bete you disit spier ese. titale: +. spier spier spier spier spier - teege . . yi 9. Would you please let me know when you have completed your examination at which time we can again get together with Dr. Smith to determine if any addit wori k io s rn eqa uirl ed WCS Jep << cc: K. W. Baith CH A. C. Bith L. A. Mair F. L. Pundsack H. G. Koch W. C. Streib PRODUCED J-M 83 Dr. K. W. Smith - GH a Research and Engineering Center November 27 1963 File 456 Brake Lining Wear Dust I am enclosing three envelopes containing dust removed from the brakes of the following cars Car Comet Newport Chevrolet Lining _ 2308 594 1618 Inlite equipment Mileage 1266 miles 540 miles 9900 miles You will find that the dust consists partly of ferrous particles presumably abrasion products from the cast iron brake drums The remainder should be predominantly abrasion products from the brake lining themselves We can supply information on the composition of the brake linings usie n td he first two cars The thi car r vd as equipped with competitive lining a composition not known to us but undoubtedly containing asbestos fiber ~ Streibi ek GK Cc W. C. Streibi C. L. MeseTVE H. G. Koch PRODUCED OF JM - 83 . a ret A MROEIER EPRI ee