The Topeka state journal. [volume] (Topeka, Kansas) 1892-1980, 1909-12-07
Powerful and Economical Is
the Secret of Their Success.
TESTING In Topeka.
Many New Experiments Tried
by Santa Fe in This City.
Other Items of General Interest
in Railroad Circles.

The most important development in
locomotive practice in the past year is
the extensive use Of Mallet locomotives
on western lines, says the Railroad Age
Gazette. These Mallet engines have
proved so successful and have showed
such remarkable fuel economy as
compared with the large consolidation
engines previously used in service that
smaller articulated engines have been
ordered for road service where there
are 1 per cent grades. These proved sc
economical that in May. 1908. 81 Maliet
engines were ordered, it having been
decided to extend the use of them to
districts having grades as low as .072
per cent.
The recent decision to convert the
consultations into articulated locomo-
tives is one of the most surprising and
far reaching movements In locomotive
practice ever witnessed in this country.
The Great Northern Is receiving from
the Baldwin works the front engine
with compound cylinders, which is in:
tended to be coupled to one OF the old
consolidation engines we have already
referred to, and the combination wi
be what we have termed a. Converted
Mallet locomotive" The f1rebox, boiler,
cylinder and running gear of the con-
solidation remain the same. The EN-
erson superheater will be fitted to the
smokebox and the new boiler she'll OF
the front engine will be fastened to it.
This new shell will not have any direct
evaporating surface, but will be filled
with tubes and usOd as q feed-water
heater, thus utilizing portion of the
heat from the waste gases which passed
out of the stack of the simple engine.
The compound cylinders in slow freight
service will produce some additional
saving in steam and fuel so that the
total economy of the complete locomo-
tive will he such that it is expected that
the CRATE surface and heating surface
of the original simple consolidation en-
CINE will be sufficient to furnish steam
for the larger and heavier articulated
engine.
The cylinders of the consolidation en-
gines are 22x30 in; driving wheels, 55
in; weight on drivers 100000 lbs; to-
tai heating surface. 2,76S So, it.: CRATE
area, SO 2 So. #. The large Mallet en-
gines on the Great Northern have horse
power cylinders 211ax32 in. a heating
surface of $500 50. TT. and a crate area
of 7S So. it., while the Mallet engine,
for ordinary road service have high
pressure cylinders 20x3O in. heating
surface of 1914 so. it and CRATE area OF
l53 SO. IT. The converted Mallet locomo-
tive will have the same cylinders. heal
ing surface and crate area as the old
consolidation, and while 1t may be said
that the heating surface and crate area
Should now be sufficient to supply the
same high pressure cylinders as before,
yet the new converted locomotive will
be much larger and heavier, with more
weight on drivers and greater tractive
power. so that whatever additional heat
IS absorbed by the engines must be de
rived from the superior economy of the
compound cylinders from the advantage
of the superheater and the saving due
to the feed-water heater.
Fuel Savers.
The high-pressure cylinders and
crate area of the smaller Mallets on
the Great Northern are smaller than
those of the consultations but the ton
mage rating has been increased nearly
80 per cent. and fuel saving on the
ton-nile basis of q per cent is OBJ
tanned on the divisions having 1 per
saving in fuel must be attributed to the
economy of the compound cylinders.
The saving of "a per cent fuel was OBJ
tanned on the % per cent grades, where
the speed was necessarily very slow.
The advantage to be derived from the
superheater in fuel economy can be ia
ken as IS to 20 Der cent.
Recent tests en- the Santa Fe show
that the latter figure has been obtained
but it is probable that portion of this
saving is due to the arrangement of
the draft rigging. which dispenses with
the battle plate and permits of the use
of large exhaust nozzles and reduces
the loss from unconsumed fuel dis
charged through the stack.
Topeka Made Test.
The economy of feed-water heaters
for locomotives has been frequently
demonstrated. and the smaller ones
which have been used on the ordinary
simple locomotives have usually given
a good account of themselves. The
larger superheater which il is possible
to use in the boiler shell of the Mall
let locomotive must exceed In efficiency
any type which has been previously
used 1t has already been demonstra-
ted on the santa Fe that or feet
of the front end of the long tubs used
with large freight locomotives can be
profitably removed and their places oc-
cupied by superheaters and feed-water
heaters. A boiler so constructed is
now beng tested at Topeka under con-
dltions where tie separate economy of