Structureless colloidal jelly that forms the base of coals and is assumed
to have been produced by the decay of plant materials.
See also:carbohumin
The maximum stress that a substance can withstand, regardless of time,
under given physical conditions, without creep.
See:fundamental jelly; carbohumin.
An old name for elaterite. Tomkeieff
A railway that negotiates a steep gradient; the cars are operated by
cables and winches. See also:mountain railway
A square funnel forming one of a series of gradually increasing size; for
separating metal-bearing slimes according to fineness.
See also:spitzkasten
Funnel-shaped fireclay piece used in the bottom-pour ingot assembly to
lead metal to the fountain brick. See also:bottom-pour ingot assembly
See:lopolith
A joint in a joint set that is concentric, with the joints dipping toward
a common center. AGI
Coolies working tin mines or other projects, in Malaysia. Hess
Eng. A deposit of chemical salts and other material (sediment) upon the
inner sides of pumps, boilers, etc. Also called: furring.
A round rod used for sounding a bloomery fire. Syn:tempering bar
Fay
a. A structure in which, with the aid of heat so produced, (1) the
operations of roasting, reduction, fusion, steam-generation, desiccation,
etc., are carried on, or, (2) as in some mines, the upcast air current is
heated, to facilitate its ascent and thus aid ventilation. Fay
b. Structure in which materials are exposed to high temperatures. Fuels
used to maintain this include alcohols, paraffins, gas, coal, hydrogen,
electricity, wood, and sulfur. A furnace is called batch type if its
contents are treated in successive charges, or continuous when a stream of
material passes through, being changed during transit. The main types are
(1) the arc, which uses the heat of an electric arc; (2) the blast
furnace; (3) the crucible furnace, a laboratory appliance for heating
small charges, or, if large, for melting metals held in bigger crucibles;
(4) the induction furnace, heated by electrically induced currents; (5)
the muffle, in which the material is placed in a sleeve not in direct
contact with the heating atmosphere, so that close control of entering and
departing gas is possible; (6) the reverberatory, in which head developed
on the roof is reflected onto a horizontal bed below; (7) the revolving
furnace, a horizontal cylinder; (8) the roasting furnace in which material
is oxidized, kilned to drive off carbon dioxide, or heated to remove
moisture. See also:cupola; continuous furnace; converter.
Pryor, 3
A barrier of firebricks or an iron-plate chamber filled with water thrown
across the furnace at the extreme end of the fire bars to prevent fuel
from being carried into the flues and to quicken the draft by contracting
the section of the current of hot gas. Fay
The zinc-cadmium oxide that accumulates in the chimneys of furnaces
smelting zinciferous ores. See also:cadmia
a. A weighing apparatus for feeding into a furnace mouth the proper
proportions of ore, fuel, etc. Standard, 2
b. In the iron and steel industry, a laborer who operates a
compressed-air-driven arm to push stock steel rails into a heating
furnace. See also:charging person
The conveyor that moves material through a furnace.
A condition by which the furnace gives much less than the normal amount of
iron at casting although the feeding may have been regular. The taphole
runs iron slowly, and the amount of cinder is somewhat scanty.
CF:furnace losing-the-iron
Refractory materials used to protect the walls of the furnace from
reaction with its molten contents (abrasive, melting, or chemical). Three
divisions are (1) acid refractories rich in silica (flint, ganister,
fireclay), which react with basic oxides; (2) neutral refractories
(chromite, graphite), and (3) basic refractories, rich in oxides of
calcium and magnesium and low in silica. Pryor, 3
Escape of iron from the hearth of a blast furnace into the foundation
beneath, indicated by decreased quantity of iron at casting and appearance
of slag at the tapping hole. Syn:losing iron
A mortar material prepared from finely ground, dead-burned magnesite;
suitable for use as a joint material in laying magnesite brick, and for
patching or daubing furnace masonry. Harbison-Walker