(2).
Tender tank capacity 6,000 gallons.
Tender coal capacity 5 tons.
Estimated weights in working orders-
On leading bogie
22 tons
On coupled wheels
55 11
Total engine
77 tons
Tender
63 tons
Total engine and tender
-
140 tons.
2. Boiler. The design of the boiler is to be of the
largest dimensions, consistent with the weight
allowed, and to follow on similar lines to that
shown on Drgs. Nos. Z.4472/15 & 16, Regn. No. 251/1.
The maximum possible grate area is to be provided
in order to satisfactorily burn coal, the calorific
value of which is only 10,000 B.T.U.
3. Firebox. The firebox is to be of the Belpaire type
with internal copper box.
Adequate facilities must
be provided for effectively washing out the water-
spaces at foundation ring.
4. Superheater. The boilers are to be fitted with
superheaters of the Marine and Locomotive Superheater
Company's type with M. & L.S. machine forged return-
bends.
Provision must be made to protect the superheater
elements from over-heating when the engine is running
with the regulator closed, by means of a snifting
valve of adequate size on the saturated side of the
superheater header.
Provision must also be made for cleaning out the
superheater flues by steam, by means of a tube cleaner
cock fixed on the side of the smokebox and using steam
from the boiler, and a flexible steam pipe with control
valve and nozzle,
8