D iagram of a Foundary Cupola for Melting Cast Iron notes and commentary

cupola furnace - вагранка at one time - одновременно lined with firebrick – облицованный огнеупорным кирпичом is usually supported on cast-iron legs – обычно поддерживается чугунными опорами swing up into position - закрываются held closed – держатся закрытыми iron upright – чугунной подпоркой refractory sand – огнеупорный песок melting of the charge – плавка загрузки swing out of the way - открываются drop down – падать вниз on one side – с одной стороны level with the bottom – на уровне с днищем breast opening – окно, летка tap hole – выпускное отверстие slag hole – шлаковая летка charging door – загрузочное отверстие

except for a metal shield – кроме металлического щита coke bed – коксовая колоша wind box – воздушная коробка the crucible zone – тигельная зона tuyere zone – фурменная зона combustion zone – зона горения preheating – (предварительный) нагрев stack zone – шахта (печи), зона отвода газов take up a space – занимать пространство the top of the coke bеd – верхний слой коксовой колоши to carry off the waste gases – выводить лишние газы roof hood - покрышка, зонт

THE BLAST FURNACE

The modern blast furnace is a tall circular structure about 100 ft. high built of firebrick and reinforced by a steel shell on the outside. The interior form is circular. A heavy concrete and brick foundation is built either on bedrock or upon heavy pilings driven deep into the earth if bedrock is too far below the surface.

Iron is reduced from the ore in the furnace by means of coke charged with ore, and the impurities are fluxed or slagged by means of limestone also charged with the ore. The air blown through the furnace is heated by means of stoves that constitute an important part of the apparatus of the blast furnace. These stoves heat the brickwork in them to about 1150°C and the air pumped through the stoves is thus heated to about 900°C before it is blown into the furnace.

The ore, coke, and limestone are conveyed from the ground to the top of the furnace by means of two cars running on an inclined hoist. The cars dump the charge into a hopper from which it is then dropped into the furnace by lowering first the upper bell, then lowering the lower bell. The use of these two bells prevents gases and flame from being blown into the air from the top of the furnace every time it is charged. Hot air is blown into the furnace through the tuyeres in the hearth of the furnace.

As the iron and slag are formed, they drop to the hearth at the bottom of the furnace. Since the iron is heavier than the slag, it settles to the bottom while the slag floats on the top of the molten iron. There are two holes in the hearth of the blast furnace. The iron is tapped from the lower hole; the slag is tapped from the upper hole. Many of the impurities in the ore are collected and removed with the limestone in the form of molten slag.

The iron runs from the furnace into troughs which convey it to a ladle. The iron in the ladle is then cast into pigs or else taken while molten to the steel making furnaces.