coal trade bulletin - Clpdigital.org

the foundations or both. Any lack of rigidity
in these elements disturbs the alignment and produces
a tendency toward heated bearings ancl increased
friction. In foundations for duplex compressors,
which are necessarily of large horizontal
dimensions, if any settlement occurs, il is
bound to be unequal; and the wide base or frame
cannot be made stiff enough to resist the distorting
forces of the settling foundation. The Angle-
Compound compressor foundation is short and narrow,
and if settlement occurs, the foundation, in
tilting from a level position, will move as a solid
block or unit, and no distortion of the frame will
result. Furthermore, this frame is of great depth
in comparison to its width, giving it a rigidity
far in excess of that found in the broad and more
flexible base supporting the duplex compressor.
The unique arrangement of the cylinders in the
Angle-Compound compressor permits the location
of both connecting rods side hy side on the same
crank pin. This feature reduces the distance
between the center lines of the two cylinders from
several f eet. in the duplex, to the width of one
connecting rod box in the Angle-Compound type,
and practically eliminates the severe distorting
forces previously referred to.
The crank shaft is supported in large bearings
immediately on either side of the crank pin. so
that the load imposed by both pistons is borne
equally by these bearings, without any tendency
to rock or spring the shaft or main frame.
The main frame of the Sullivan Angle-Compound
compressor is horizontal, and supports the
entire machine. To one end is attached the low
pressure cylinder and on the other is bolted an
upright pedestal, which carries the vertical or
high pressure cylinder. This main frame is of
the heavy duty, Tangye pattern, strongly ribbed,
with bored guides for the low pressure crosshead,
and planed jaws to receive the crank shaft boxes.
There are openings in the sides, to afford access
to the crosshead, protected by oil-tight covers.
The bottom is solid, and forms a reservoir for oil.
The rear end is faced and counterbored for attaching
the low pressure cylinder.
The vertical frame or pedestal is of similar design,
and has a broad base, secured by heavy bolts
to the top of the front end of the main frame. In
addition to the openings opposite the crosshead,
others are provided on the front and sides, likewise
fitted with tight covers, to give free access
to the crank pin and crank shaft boxes.
The main bearings are made in four parts, of
cast iron, lined with babbitt, with set screw adjustment,
and so designed that all four parts may
be taken out without removing the main shaft.
The cross heads are of cast iron, of a strong
box form, fitted with shoes with babbitted faces,
turned to fit the bore in the frame, and provided
THE COAL TRADE BULLETIN. 49
with wedge adjustment. The crosshead pins have
taper fits in the crossheads, and are secured by
lock nuts.
The connecting rods are forged from open hearth
steel billets, with marine type boxes on the crank
pin ends, lined with babbitt. The crosshead ends
are solid and slotted for the reception of bronze
boxes, provided with wedge and screw adjustment.
The crank shaft is a heavy, open hearth steel
forging, of the center crank type. The crank
pin is of a proper length to accommodate both connecting
rod boxes on it, side by side. A heavy
cast-iron counterweight is bolted to each crank
check, equaling the whole weight of the reciprocating
parts of either the high or low pressure
member. The centrifugal effect of these weights
neutralizes the inertia of both sets of reciprocating
parts, so that the compressor runs at full rated
Sullivan Angle-Compound Air Compressor. Showing Operation
on Short Center Drive From a Motor. By Means
of a Belt-tightener.
speed without perceptible vibration. The crank
shaft extends from one side of the machine to
receive the driving pulley or motor, and in all
except the smallest sizes, is provided with an
out-board bearing, consisting of a babbitted box,
carried in a heavy pillow block upon a strong sole
plate, which is bolted to the foundation. Set
screws and wedges permit adjustment both vertically
and horizontally, so that this bearing may
always be kept in correct alignment with the
crank shaft bearings.
The band flywheel or pulley is of sufficient
weight to give steady motion to the compressor,
at its rated speed. It is made in halves, held together
at the rim and hub by heavy through bolts,
and is keyed to the shaft. The face of the wheel
is turned crowning to receive the driving belt.
When desired, the compressor may lie driven
by an electric motor mounted directly on the
crank shaft. In this case the regular belt pulleris
replaced by a heavy, square rimmed flywheel,
securely keyed to the shaft, close to the com-