Instruction 2111.80B 04/05 6
B. HORIZONTAL
Pumps and drivers that are received from the factory with both machines mounted on a common base
plate, were accurately aligned before shipment. Units are shipped with coupling halves separated and
require coupling realignment at installation. All base plates are flexible to some extent and therefore must
not be relied upon to maintain factory alignment. Realignments necessary after the complete unit has been
leveled on the foundation, and again after the grout has been set and foundation bolts have been tightened. The
alignment must be checked after the unit is piped, and rechecked periodically.
6. GROUTING
Non-shrink grout is generally made up of a mixture of one part pure cement and two parts sand with sufficient
water to cause the mixture to flow. A wooden form should be built around the outside of the base of the
pump, and the pump base plate or pedestal should be completely filled with grout. This will provide ahead to
force the grout into all the cracks and crevices, and prevent the grout from shrinking away from the base as it
sets. Before and after the grout has been hardened, the nuts on the foundation bolts should be tested for
tightness, and the pump should be checked to see that it has not shifted from its correct position. Alignment of
couplings must be checked after any adjustment to the unit.
7. PIPING CONNECTIONS
The suction and discharge pipes must be independently supported near the pump so that no strain will be
transmitted to the pump casing. Provisions should also be made for pipe expansion and contraction so that no
strain is placed on the pump. A generous, grooved, square hole should be left when running a pipe through a
concrete wall, and the pipe should be grouted in only after the pump unit is set and all final connections have been
made. If an expansion joint or pipe coupling is to be used between the pump unit and the nearest point of
anchor in the piping (i.e. a wall), it is essential that the joint / coupling be axially rigid to offset the pressure
increase which would otherwise be exerted on the pump.
Suction and discharge pipe lines must not be smaller in size than the connections on the pump. Piping should be
arranged with as few bends as possible, and should be made with long radius elbows when feasible, to
reduce the loss of head due to friction.
Consult the factory when handling liquids above 40°C (104°F.)
CAUTION
THE PUMP SHOULD NEVER BE THROTTLED BY THE USE OF A VALVE ON THE SUCTION SIDE OF THE PUMP.
Suction Piping
The suction piping must be kept free of air leaks. Air that remains entrapped in the piping after the pump
has been primed and started will eventually be drawn into the pump. This may cause the pump to cavitate or
lose its prime. This situation can usually be temporarily remedied by priming and starting the pump several
times. This will draw enough air from the entrapped pockets so that the pump will operate properly, but the
trouble is likely to reoccur until such a pocket is eliminated.
Some vapor, released by the partial vacuum in the suction pipe occurs naturally in the pumpage. This vapor,
added to small amounts of air admitted through minute leaks in the pipe connections, must not be allowed to
build-up. Excessive air pockets can be eliminated by following these guidelines:
a. If the pump operates with a suction lift, the suction pipe must slope upward to the pump nozzle and
downward to the source of supply. If the suction pipe is installed higher than the pump nozzle, an air pocket
will form at the highest point
b. In a horizontal suction line, an eccentric reducer installed flat side up must always be used in lieu of a
concentric reducer. Use of a concentric reducer will cause air pockets to form in the top of the reducer and
suction line.
c. If a gate valve is used in the suction line, it should be installed with the stem in a horizontal position.
Vertical positioning allows air to become trapped in the bonnet of the valve.
Wet well design should always be in accordance with Hydraulic Institute Standards.
Consult the factory for anything other than individual piped suction installations.
CAUTION
RESTRICTED FLOW VALVES SHOULD NEVER BE USED ON THE SUCTION SIDE OF THE
PUMP. ALL VALVES MUST BE OF A FULL FLOW TYPE.
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