Donald B. Wagner, Background to the Great Leap Forward in Iron and Steel
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Construction and operation of a blast furnace for iron smelting from ironsand in Dabieshan according to Guo Yujing, 1932
The original gives
dimensions in English units and weights in Chinese units; in the
translation these are converted to metric. The text has no
illustrations, but the diagram below, from 1958, fits the description
The blast furnace, or ‘sand-smelting furnace’, has the following dimensions:
• height 183–244 cm
• upper diameter 66–104 cm
• middle diameter 36–86 cm
• lower diameter 41–94 cm
It is divided into an upper and a lower section. The outside is hooped with iron bands, four each on the upper and lower sections. These are joined together by several straight iron rods. . . .
The area around the taphole is the
subject to melting. In Xinyang, sandstone from Jiayu County, Hubei, is
used [for the taphole stones]; in Shangcheng, diatomaceous earth from
Qishui [modern Xishui], Hubei, is used. The two materials are equally
Materials for furnace construction
Loess and sand are used, together with unburnt charcoal from furnace slag, washed and powdered. This is called ‘charcoal powder’. The loess is mixed with sand and charcoal powder and plastered evenly on the inside of the furnace. The proportion of loess to white sand is ca. 100 to 34. When this has dried, charcoal powder is plastered over the whole; then the furnace is ready. At the bottom, where the temperature is highest, old taphole stones (diatomaceous earth) and a small amount of salt are added to the charcoal, loess, and sand.
The material is the same as above.
This is formed into a long tube, 61 cm long, with outer diameter 10 cm,
inner diameter 5 cm, weight ca. 20 kg. One furnace uses four
tuyères every 24 hours. The
most important detail in the installation of the tuyère is its
angle: the blast should be directed precisely toward the taphole.
Otherwise the temperature will be insufficient.
A wooden windbox is used for the
blast. It is 213 cm long, with inner diameter 30 cm, outer diameter 41
cm. Valves are installed inside. The shaft is 366 cm long. It is worked
by two persons.