. American engineer . arefully designed and keptproperly adjusted. CASE HARDENING William Nicholson (C. P. R., Montreal, Can.) :—Case-hardening results are dependent wholly upon the character ofthe metal, the carbonizing material, the temperature of the fur-nace, length of time the work is subjected to the carbonizingheat, and the lieat treatment following the carbonizing work to be case-hardened at the Angus shops is packedin bone black with a covering of about Yi in. of the same mate-rial and the pieces are separated by scrap leather. This will re-cjuire about 6^? hours of heatin
. American engineer . arefully designed and keptproperly adjusted. CASE HARDENING William Nicholson (C. P. R., Montreal, Can.) :—Case-hardening results are dependent wholly upon the character ofthe metal, the carbonizing material, the temperature of the fur-nace, length of time the work is subjected to the carbonizingheat, and the lieat treatment following the carbonizing work to be case-hardened at the Angus shops is packedin bone black with a covering of about Yi in. of the same mate-rial and the pieces are separated by scrap leather. This will re-cjuire about 6^? hours of heating from the cold furnace, and wehave always had good results. G. Creeden (B. & A., Springlield, Mass.) :—We have one an-nealing Ferguson furnace, 72 in. x 30 in. x 28 in., where wedo all case-hardenmg and annealing. We use cast iron boxesand pack the steel in charcoal. The boxes are placed in thefurnace in the morning and heated to about deg. F. forabout 9 hours. The furnace is shut down at night and the. paraffin oil and 25 gal. of lard oil with 2 bushels of fine table salt-There is a /2 in. pipe at the bottom of the tank with 1/16 in_holes 6 in. apart, through which air is blown before dipping;the cutters, so as to thoroughly mix up the entire the air is shut off and the oil has settled, put the cutters,in and move them about until cool. Discussion—I. F. Hoeflle (L. & N., Louisville, Ky.) :—Weuse a liquid potash of 2.^ parts bichromate of potash, 5 parts-Prussic potash and 10 parts of salt, which gives good results. G. Lindsay (E. & T. H., Evansville. Ind.) :—We have dis-continued using the combination mentioned by Mr. Hoefifle, left a rough surface on the work. 1 do not believe it is-necessary to case-harden as deeply as we do, for we neverwear all the way through the skin. Four hours is plenty. Geo Hutton (N. Y. C, W. Albany, N. Y.) :—We use a com- Flg. 1 — Dies for Forminn Ends of Grab Irons; Lehigh Valley. boxes remain in them unt
Size: 1576px × 1585px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectrailroa, bookyear1912
