Wedge furnace

Multiple-Hea.rth Roasters. The circular types consist of a series of hearths arranged vertically in such a way that the ore entering the top is rabbled and dropped down from hearth to hearth, until it is completely oxidized. The hearths are usually stationary and the plows revolve, such as in the Wedge, Herreshoff, Ord, Skinner, and other roasters (21). In other furnaces, the hearths revolve and the rabbles are fixed, eg, the deSpirlet and its modification, the Barrier. 

Another initial problem encountered was several grate bars popped out of place, exiting at the end of the inclined floor of the boiler. Engineers determined that the fluctuations in steam load and on/off cycling of the furnace were allowing ash and slag to be wedged in the spaces between bars and to lift the bars out of place.6... 

Wedge 1 furnaces are employed when fines alone require to be dealt with, and are more efficient than open practice. The ore if over-size 1 See A. W. G. Wilson, Pyrites in Canada. 

Refractory ware is manufactured in a wide variety of shapes. Rectangular and wedge-shaped blocks of smaller sizes are commonest. Manufacture of large-size blocks (e.g. for glass furnaces) requires special care in the preparation of mixes, forming, drying as well as firing. Frequent use is made of non-standard shapes made to order even in small quantities. 

Workers were fesfing fhe deacfivafion furnace May 8, after destroying the last of fhe sarin nerve agenf stored at the Anniston Army Depot in March. At about 10 p.m. that night, 72 carbon-steel bolts, which held the 7-foot-diameter, cylindrical steel furnace suspended above the ground, broke. The tower portion of the furnace fell away and became wedged 10 to 15 feet above the ground in a steel-beam frame around the furnace. 

The furnace is heated with silicon carbide resistant elements to 1600 °C. The samples were impacted in the furnace by a pendulum hammer having a 23.65 in. arm length and a 0.411 lbs wedge-shaped, sintered alumina head, as shown in Fig. 2.2. 

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