Document g2e46J8NZ6OBxmG9Dm4JKyzVa

Preliminary Dust Survey for Asbestos Textile Institute, Jure, 191*7. 6 cooTAnlco provea that it does not interfere seriously with nanufacturlng operations nor vith quality of roving produced. Our Investigations Indicate the superior advantages of having side walls of the enclosure of wood to facilitate small clearance by rubbing con tact at the edge of the rain cylinder, thus avoiding excessive air infiltra tion at that point. V/ood covers tave the advantage of resistance to crushing, vhich was evident in installations with sheet,natal covers. * Connection of the enclosure to the exhaust syeten by ceans of chan- bers of emple dimensions, l.e., large cross-sectional area is of major in-, portance to avoid localized high air velocities class to the webbing in the main cylindor. This detail was not always observed. In view of similar degrees of success, Judged by dust counts, be tween'various installations, the best criterion of superior design os to de tails of exhaust from the rachlno was in the relative oconcxy respecting volume of air exhausted per machine. Our observations indicated rather ex treme variations, as indicated in the following table of exhaust rates per carding set in five representative plants: Plant Air Exhausted Far Set * lj A ''o'* I..-*"' CA .s . c a \h-\ 1500 cfn 2200 cfn 3800 cfn 5I00 cm eqoo cm It is apparent from tills investigation that 2000-2500 cfn per set of brcaicor and flnloher cards is ample exhaust capacity if the system is properly dcaigncd. MTS 007899