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POWER END AND GEAR REDUCTION
UNIT LUBE SYSTEM (FIGURE 2-2,
FIGURE 2-3, and FIGURE 2-4,)
Both the gear reduction unit and power end
have individual lube oil inlets. The power
end inlet is located at the rear of the pump.
The inlet is a 1-1/2” NPTF tee which divides
the lube flow between the lube manifold for
the crosshead guide and the rotary union.
Pressurized lubrication for each crosshead
is delivered from the lube manifold through
the underside of the crosshead guide. An
aluminum cover houses the rotary union,
which is attached to the crankshaft.
Lubrication for the power end components
comes from forced lube through the
crankshaft. Lube oil enters the crankshaft
and first lubricates the #4 main bearing. Oil
from the main bearing also lubes the thrust
bearing. As oil reaches the first crankshaft
journal, oil exits the journal oil hole and
lubes the journal and journal bearings,
passes through the center of the connecting
rod to the wrist pin and bushing. It then
reaches the knuckle bearing and then to the
crosshead. This is repeated for the rest of
the main bearing cylinder components. Oil
is removed from the power end through a
primary 4” drain in the bottom of the frame
in the center cylinder. Oil passages at the
forward part of the frame members allow
the end cylinders to drain to the center. Oil
is also drained from three 1” crosshead
drains located at
the forward end of each cylinder in the
bottom of the crosshead guide. These three
drains are combined together and empty
into the main drain external to the frame.
The gear reduction unit has one inlet
located on the upper input side of the offset
section. This is a 1-1/2” NPTF on a bronze
“Y-type” strainer mounted on a distribution
block. From the distribution block the input
and output gears and bearings and
planetary section are lubricated through a
spray bar, nozzle, and orifices.
The lube oil is drained from the gear
reduction unit through two SAE 2” 4 bolt
split flange drains located on the offset
section housing and one 1-1/2” NPTF drain
on the transition section connected to the
power frame. It is important that these drain
hose sizes are maintained to the primary
drain and include as few restrictions and
direction changes as is practical. Gear unit
heating problems are most often related to
drain restrictions causing buildup of oil
inside the unit, thus generating excessive
heat.
NOTICE
It is also extremely important to
maintain some downward slope in the
entire drain system back to the lube
reservoir
.
FIGURE 2-4 GD 3000 Gear Reduction Unit
