![](http://www.alamy.com/thumbs/6/8D887071-576B-4267-889F-18277304CEF4/2ANFGFG.jpg)
Canadian foundryman (1917) . ly when values areincreased and wastage prevails throughdefective treatment and careless is an actual fact that the shortageof this material which was threatenedsome time ago was in part due to care-lessness and lack of facilities for proper hardening and in the course ofevents it was hut natural that the onusof the situation would gravitate towardsthe makers as the source of the ma-terial. As the leading makers of highspeed steel in this country, ArmstrongWhitworth, .Montreal, were in aunique position to appreciate the factorsof the situation, the r
Canadian foundryman (1917) . ly when values areincreased and wastage prevails throughdefective treatment and careless is an actual fact that the shortageof this material which was threatenedsome time ago was in part due to care-lessness and lack of facilities for proper hardening and in the course ofevents it was hut natural that the onusof the situation would gravitate towardsthe makers as the source of the ma-terial. As the leading makers of highspeed steel in this country, ArmstrongWhitworth, .Montreal, were in aunique position to appreciate the factorsof the situation, the result being thatthey have developed, and are now mar-keting a hardening furnace for highspeed steel which enables the full bene-fits of this material to be obtained bythe average user. The furnace is of the twin muffle typeand oil-fired, the appearance and con- enters, the flame impinging on the cur-ved surface of baffle brick B whence itproceeds around each side of the cham-ber and underneath the hearth (, finally Z2& .. (Mi. 1 front VIEW OF TWIN MUFFLE FURNACE FOR HARDENING HIGH-SPPED STEEL ascending past the semi-muffle walls Di the rectangular exit in the archedroof. This arrangement prevents theproducts of combustion from coming inst ruction being .dearly indicated in the contact with the work and insures aaccompanying illustrations. Fig. 1 is a very even degree of heat throughouttront view, the two chambers being of the chamber. solid fire brick construction, built into The twin chamber arrangement pro-mi angle iron frame work, the whole vides ideal conditions for the harden-being carried on a braced frame of the ing of high speed steel. The left handsame material. The internal design is chamber is used for preheating pi,r-shown in Fig. 2. An opening A is poses only, the steel bein- slowly andprovided at the back of each chamber, evenly heated to about 1400 de°- Fthrough which the oil and air mixture when it is transferred to the right-hand chamber which heats it quickly
Size: 1466px × 1704px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., boo, bookcentury1900, bookdecade1910, bookidcanfoundryman1917toro