Document 4JD8Xxk0bRVO54kXRMwEomXoj

Finishing cement, Du Pont Code 712, has been removed from Standards as it by nature was a high asbestos quantity material. Treated, woven glass cloths have been found, by lab tests and field trials, to be a satisfactory substitute for woven asbestos "A" cloths. The treated woven glass cloths showed no deterioration at temperatures of 1000 F, and they accepted the standard in sulation finish coatings very well. They even showed no deteri oration when cemented to calcium silicate insulation with a heavy coat of lagging adhesive or sodium silicate; and the insulation subsequently kept wet. / t The sodium silicate cemented glass cloths, however, did have an unsatisfactory rate of deterioration when placed against hot surfaces at 300 F and above. In applications of the sodium silicate cemented, treated glass cloths that do not contact hot surfaces we have found the follow ing materials satisfactory substitutes for asbestos "A" cloths: J. P. Stevens and Co., Inc. Style 1925/9351 "double coated" and Style S4205/93.51 "double coated" "Nomex" woven cloth cemented to calcium silicate with sodium silicate, has also been found to be a satisfactory substitute for "A" clothes in contact surface temperatures up to 600F. The "Nomex" works well with the sodium silicate "Adhesive and accepts standard insulation finish coatings very well. It can be ordered from Globe Albany Corp., Buffalo, N.T., in 100 yd. rolls and would be designated "Nomex" N-7304. dup 0902070