. The Street railway journal . en giving such good re-sults on a number of roads that some particulars on this sub-ject may prove of interest. The apparatus consists of a vacuum chamber and impreg-nating liquor tank, a combined condenser and receiver and adry vacuum pump, with the necessary auxiliaries. The cham-ber is constructed to maintain an extremely high vacuum andan air pressure of at least 60 lbs. to the square inch. The coilsto be treated are first placed in the vacuum chamber, a highvacuum is then obtained and the moisture is abstracted rapidlyat the lowest possible temperature. The
. The Street railway journal . en giving such good re-sults on a number of roads that some particulars on this sub-ject may prove of interest. The apparatus consists of a vacuum chamber and impreg-nating liquor tank, a combined condenser and receiver and adry vacuum pump, with the necessary auxiliaries. The cham-ber is constructed to maintain an extremely high vacuum andan air pressure of at least 60 lbs. to the square inch. The coilsto be treated are first placed in the vacuum chamber, a highvacuum is then obtained and the moisture is abstracted rapidlyat the lowest possible temperature. The vacuum chamber andcondenser are provided with observation glasses and by-passvalves, which permit an ocular demonstration of the moistureleaving the coils being dried. When the moisture ceases, thecoils are absolutely dry and ready for impregnating. The impregnating compound is heated, and if a solid com-pound is melted in the impregnating liquor tank, which is con-nected with the vacuum chamber. The latter is so arranged that. VACUUM DRYER FOR FIELD AND ARMATURE, COILS the compound is allowed to enter the vacuum chamber withoutbreaking the vacuum. This eliminates any possibility of thedried coils absorbing moisture, as is the case in the old-fash-ioned method of drying and impregnating in bake ovens andflip tanks. Arrangements are also provided for overcoming thefreezing or solidifying of the compound in the connecting pipesbetween the vacuum chamber and the impregnating liquor vacuum chamber is provided with facilities for accuratelydetermining the temperature of the materials being dried, aswell as of the insulating compounds. The apparatus is so con-structed that any insulating compound can be used. Whensolid compounds, with a high melting point, are used, specialarrangements are made to obtain the highest possible tempera-lure and to prevent the material from coking or caking, whichhas heretofore been one of the greatest difficulties with solidcompounds. After the
Size: 1981px × 1261px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectstreetr, bookyear1884
