B. - High-duty Apparatus. -
2. Blast-Furnace Blowing-Engines.-
(a)Walking-beam Machines. Fig. 133 shows the disposition
of the machine used at Ebbw Vale, Wales. This engine, owing to
its size, is probably the most powerful of its class extant.
The dimensions are as follows: Motor, diameter of steam-piston,
71.5 inches; stroke, 142.7 inches; length of walking-beam, 35
feet 7 inches; fly-wheel, diameter, 30 feet 7 inches; weight,
85 tons; air-cylinder, diameter of piston, 142.7 inches; area
of same, 112 square feet 86 square inches; stroke, 142.7 inches;
volume of cylinder, 1,358 cubic feet 818 cubic inches; revolutions
per minute, 16; velocity of piston per second, 6 feet 4 inches;
theoretic volume generated per minute, 43,496 cubic feet; absolute
pressure of blast, 1.3 atmosphere; volume of air theoretically
furnished at this pressure, 33,458 cubic feet.