diameter and 24 in. stroke.
The two coupled wheels under the barrel of the boiler are 5 ft. 6 in.
diameter, and the trailing wheels 4 ft. 6 in.; there are single frames
with inside bearings to all the axles. The boiler pressure is 140 lb., and
the tractive force per pound of mean cylinder pressure 106 lb.; the total
wheel base is 14 ft. 6 in. The boiler is 10 ft. 2 in. long and 4 ft. 4 in.
diameter, and the heating surface is in the tubes, 858 square feet;
fire-box, 90 square feet; total, 948 square feet. The engine is furnished
with wing tanks holding 860 gallons of water, and carries 30 cwt. of coal.
The weight in working order is 38 tons. These engines have taken a maximum
load of twenty-five coaches between London and Brighton, but are mainly
employed in working the suburban and branch line traffic; their average
consumption of coal is 23.5 lb. per mile, with trains averaging about ten
coaches.
Another example is Mr. Webb's tank engine on the North-Western Railway,
which presents a contrast to the foregoing. It has inside cylinders 17 in.
diameter and 20 in. stroke, coupled wheels 4 ft. 6 in. diameter, and a
tractive power per lb. of mean cylinder pressure of 107 lb.
Pages:
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103