THE ARTILLERY WORKS OF MESSRS.
SCHNEIDER AND CO., AT CREUSOT.
167
types ; two groups consist each of two tubular boilers
with corrugated fireboxes ; a third group is formed of
two multitubular boilers. The grate area is 22.50 square
metres (242.19 sq. ft.); the total heating surface, 1000
square metres (10,764.30 sq. ft.). The two groups provide
sufficient steam for working under füll load ; the third
group is kept in reserve. The three steam engines are
100 horse power (one engine) :
Diameter of small cylinder ... ... .280 m. = IL in.
,, large ,, ... ... .420 m. = 161 in.
Stroke____________________________320 m. = 12$ in.
Revolutions per minute ... ... 270
The current from each dynamo is 225 volts; the
distribution is eftected through three mains, and the two
dynamos being connected to the driving pulley by two
Fig. 564. Shrinking Jacket on 240-Millimetre Gun.
compound, and work under an initial pressure oi 7 kilo-
grammes (99.5 1b. per square inch). Each one drives by
means of a single belt, two direct-current Tlmry generating
dynamos built by Messrs. Schneider and Co. The steam
engines are of two types, and are of the following
principal dimensions :
300 horse power (two engines) :
Diameter of small cylinders...
,, large ,,
Stroke ...
Revolutions per minute
... .450 m. = 17J in.
... .650 ni. = 25g in.
... .650 ni. = 25$.in.
165
elastic clutches, are coupled in tension, and give 450 volts
on the two outside lines of the distribution. An electric
regulator maintains the voltage constant, whatever be the
output. The three groupe of generating dynamos can be
connected in multiple arc; the 100 liorse-power group,
however, is more especially used for night service.
The three mains are laid overhead, and consist of
uninsulated cables ; they supply, direct, all the fixed motors
tbat drive the transmission shafts of the north and soutli
shops, and a few machine-tool motors ; they also supply the