162 A. DAIGGER & COMPANY, CHICAGO, U. S. A. 



FURNACES HOSKINS' ELECTRIC 



TYPE FD 



These furnaces, Type FD, are designed for industrial and laboratory purposes. 

 Their construction eliminates all the shortcomings commonly found in wire-wound 

 electric furnaces. Attention is particularly called to the fact that all parts of this 

 furnace which require renewals are very easily accessible and can be replaced by the 

 operator himself. No part of this furnace need be returned to the factory when in need 

 of repairs. 



The heating unit is surrounded by bonded kieselguhr, backed up with asbestos and 

 magnesia slabs. It is believed that this insulation is the most efficient that is available 

 and it is responsible for the low power consumption of this FD line. 



The door of the furnace is of the sliding type and has an adjustable counterbalance, 

 which causes the door to remain open at any desired point or close automatically. 



Construction The heating element in these furnaces is of heavy Chromel "A" 

 wire, wound in spiral coils. The refractory, around which this wire is wound, has 

 spirally built ribs on its surface, which give the walls of the heating-chamber a greater 

 strength, and at the same time the spaces between these ribs act as grooves in which 

 the wire is wound and is thus automatically and properly spaced. 



Temperature The maximum safe operating temperature of the FD Furnace is 

 1830 F. (1000 C). The minimum temperature that can be maintained with the 

 standard rheostat is about 900 F. (480 C.). With special rheostats, they can of course 

 be operated at lower temperatures, with the exception of the Tube Furnace. 



Operation Hoskins Furnaces, Type FD, are built for 110 or 220 volt circuits, alter- 

 nating and direct current. Special windings will be made for any voltage between 100 

 and 300. All styles require the use of a rheostat, which is the only auxiliary apparatus 

 required. 



291G(a) 291G(b) 



2916 (a) FURNACE Hoskins' Electric (Type FD), No. 101. Crucible chamber style, 



as shown; may be titled on its side and used for a small muffle. Particularly 



for making crucible combustions, incinerations and melting alloys within 



temperature range of furnace. Includes 6 feet twin connector, cord and 



attachment plug. 



2916(b) Recalescent Outfit The apparatus shown in 2916(b) is used for deter- 

 mining the "critical points" of high carbon steels. It consists of 

 Hoskins Type FD-101 electric furnace, with controlling rheostat, and 

 Type PA Portable Meter and thermo-couple Type P-402, complete 

 with handle and 10 feet of flexible leads $74.50 



