The sun. [volume] (New York [N.Y.]) 1833-1916, 1898-06-19
NOVEL AMONG BIG LINERS.
INNOVATIONS IN THE CONSTRUCTION
OF THE KAISER FREIDRICH.

Nv NOW OOO-loub bbphhl1hiP VI NhV NSAhA
German Lloyd Steamship Company, the Kaiser
Friedrich, which arrived at her pier in Hobo
kon last Thursday on her maiden voyage, con-
tains som features which are novel in ocean
liners. One of these 10 the arrangement OF her
engines as related to the screws and their place
in the hull. In every other large screw
steamer, and in most email ones, tho rule has
been to place the boilers and coal bunkers
amidship. with the engines Immediately astern
Of the boiler rooms. While comparatively
low engine power was used this arrangement
was satisfactory, and no one conceived that
there would ever be any necessity Of changing
It. 1t brought the boilers and coal bunkers to-
gethor. tho ship was coaled with convenience,
and tho engines being well aft, tho connections
between them and the screws were made directly
by comparatively short lengths OF shafting.
and with few bearings for the lines OF shaftinE.
But In meeting the demand for constantly in
crcasing horse power and greater speed an OBJ
staclo was encountered which commanded the
attention OF marine engineers. This was the
vibration set up in tho hulls Of the vessels by
the tremendous engines running at high speed.
This vibration 10 not only n source OF discomfort
to all on board, but Of concern to those who are
responsible for the continued life Of the ships.
Those who have trave !led on ocean grcyhoundS
or upon such fast screw steamers as the Mon.
mouth and Sandy Hook of the New Jersey
Southern Railroad line can realize what a strain
vibration produces. On tho Jersey Southern
boats it is very manifest. When these boats
are going ahead at full speed the hulls culver
from stem to stern, and when the engines are
reversed it seoms AS II the after portion of the
boats would be wrenched loose from the rest Of
the vessel.
The boats trembls and squirm In a way that
reminds one Of a snake writhing In Its whole
Nu-.l a., zAt ,,..v frnp, ,,n,n qua traaJtnr ,,,,an
its tail.
With the advent In naval architecture of the
fast torpedo boat and later OF the bigger and
faster torpedo boat destroyer, this difficulty
was accumulated. Vessels Of this class, built
ten times as long as they are wide, and with a
speed that increased rapidly from twenty TO
thirtY-four knots an hour, were of necessity con-
structed with hulls Of as little weight as posi-
bic. Although special designs were adopted to
| give strength and stiffness, the tremendous en-
CINE power set the hulls to wrlthing and CULVER
ing SO that 1t became imperative to devise some
way to obviate this. 1t was suggested that q
remedy might be found in placing the engi mes
nearer amidships. and this has been done in q
number of cases with good results.
The advantage Of this plan Is demonstrated
II you take a long stick, and, holding it by-one
end. shake it. A wave of vibration will be set
up in the stick, beginning at the end where 1t
is held and extending throughout the whole
length. If the grip be moved toward the centre
of the stick and the same power applied in
shaking it, 1t will be found that the waves of
vibration decrease. and that they grow less
and less as the grip approaches the centre of tho
stick. Although the vibrations OF the engine
are all within the hull of the vessel. they pro-
duce effects upon the ship in much the same way.
Before the building Of the Kaiser Friedrich
other methods had been tried in big ships TO
overcome vibration. In the bigger Kaiser
| Wibnlp, dor Ernaaa Hniahal Ia at yRur for tbn
same line, n special arrangement OF the engines
was adopted whereby the moving weights were
thor. Efforts have also been made in the di.
rection OF building balanced engines for loco.
motives for overcoming similar troubles in fast
railroad work. Although the Kaiser Friedrich
Is shorter than the Kaiser Wilhelm der Crosse,
teed her to beat that record breaker by half a
Knot an hour, and in order to overcome the vi
bration which her $4,000 horsepower engines
would tend to produce, the arrangement here
tofore used only in torpedo boats was adopted.
Incidental to the placing Of the engines nearer
rangement was made. which had also been
utilized in torpedo boats. This was to divide
the clusters of boilers and place one cluster aft
OF the engines. Tnis Arrangement, while per-
haps made necessary by the taking up of mid.
ship space for tie engines, probably has a dis
tinct advantage, also, in reducing vibration.
Any one who has watched n steam drill at
work has noticed that the workmen in charge.
after placing the drill in position, hang iron
weights upon each leg Of the frame to keep tho
drill from jumping about as the piston works
up ulu oo"h' uliNlnB wv III NV ~ LoSh.
In the same way that the inertia Of these
weights acts to stop the vibrations Of the drill.
Ing machine, so the weight Of sets OF boilers and
coal bunkers, placed Ground the steamers en-
gines, must work in resisting their vibratory Of.
fscts The officers and other persons Interested
the Kaiser Friedrich proved to be very steady
and free from vibration, and in this regard 1t
may be assumed that the arrangement OF her
engines amidshlps has answered the expecta-
tions of her builders.
There is another question which this new ar
rangement has raised, which, however, can
only DO answered by the results Of experience.
That Is as:to;how:the use Of the extraordinariIy
The shafts OF modern hiEh.power steamers are
: frequent seat i iOf trouble derr1in Not &c tn only y do fht they .G
are liable to heat and bind with the slightest
that the chief seat Of trouble is with what is
known as the tail shaft. the section which runs
Here tho shaft is liable to its greatest side
strains, and corrosion often plays an important
tRS S5s IN wS MieGhNs earPg Il tho csnSE :' and the pSf sections r5a
aft Of these known as tho thrust shaft
where the friction OF the thrust Of the screws ID
taken up by a series OF rings on the shaft.
But there is trouble frequently enough In
the line shaft between the thrust shaft apd the
tail shaft. Flaws IN these sections lead to break
age when extraordinary strains occur, and the
benrings, too. may heat or grind; In the or,
binary big ship the shafts are perhaps 100 feet
long. In the Kaiser Friedrich their totaI
length is about 24t feet. To be exact. the two
s4astS !. OF nh the c aS% sn b2 are = S, q GsnesG in t ISnE Dosi
tion OF the engines. but in those of the screws
Tho two engines stand side by side. and the
shafts from them run aft about parallel. buI
they emerge from the sides under the stern toe
close together to allow of the two 20 foot, 4
inch diameter propellors working side by side
The propellers overlap, and to provide for thil
the port propeller is placed further aft than thu
Starboard ono, and It's shaft is therefore some
what longer.
The crank shafts. tho thrust, and the tai
shafts a'e OF the customary length. and all thu
extra length duo to the placing Of the engineI
amldship Instead OF aft is added to the connect
ing line shafts. The latter are in five ~sectionI
and rest on ten bearings. The ~shafting IL near
~ two feet In diameter 1t is hollow and o
nickel steel. That there is an added danger o
fracture for each section ID u mechanical
axiom. The strength OF the whole is meas
ured by the strength OF its weakest part" 10 thu
rule. This, however, need not be: considered
serious element VI danger in tho long shaft, bo
! cause accidents to this part OF a ships shaft
do not often occur through defects In the parts
4 But, on ~the:other hand, engineers agree that II
making long lines of shaftiHg in places where 40
!. soIuto alignment cannot be depended upon Their
i Is always danger. A very slight twisting of til,
hull of the ship would grin tho shaft IN. The bear
/ ings and heat them or even crack the shaft il
tVFa Fltn. L., 80 y a., wFt1l NA N-nN l.