be suitable for outdoor installation. The unit, consisting of
vertical shaft, [single] [multistage] propeller type pump and
motor shall be designed to operate safely in the reverse direction
of rotation, due to water returning through the pump. The weight
of the revolving parts of the pump, including the unbalanced
hydraulic thrust of the propeller, shall be carried by a thrust
bearing in the motor. The pump shall be supported from a base
plate by means of a vertical column having horizontal discharge
located below the base plate.
b.
Pump Characteristics: Pump number(s) [_____] shall have the
following operating characteristics:
(1)
Pump Service.
(2) Design Operating Point: [_____] L per second gpm flow,
[_____] mm feet head, [_____] percent efficiency.
(3) Maximum Operating Point: [_____] L per second gpm flow,
[_____] mm feet head, [_____] percent efficiency.
(4) Minimum Operating Point: [_____] L per second gpm flow,
[_____] mm feet head, [_____] percent efficiency.
(5)
Propeller Type:
[_____].
(6)
Discharge Diameter:
[_____] mm inch.
(7)
Bell Diameter:
[_____] mm inch.
(8)
Column Length:
[_____] mm feet.
(9)
Operating Speed:
[_____] rpm.
(10)
Minimum Bell Submergence:
[_____] mm inch.
(11)
Pump Control:
[_____].
c.
Pump Column and Discharge Elbow: The pump supporting column shall
be made of steel pipe with a minimum [6] [_____] mm [1/4] [_____]
inch thickness. The discharge opening shall be flanged for
connection to the discharge pipe. The discharge elbow shall be
the long radius type, and shall be of [welded steel] [cast-iron].
d.
Base Plate: The pumping unit shall be suspended from a base plate
of adequate structural design to support the weight of the
complete unit filled with water. The base plate shall be cast
iron or steel and shall be sized to allow the entire pump to be
removed, with the discharge flange attached; base plate mounting
hardware shall be stainless steel. The packing box shall be
located on or above the base plate to provide for easy
maintenance. The motor shall be mounted above the pump.
e.
Suction Bell and Impeller Housing: The suction bell and impeller
housing shall be made of [ductile] [cast] iron [_____] and shall
be designed for easy removal of the propeller and lower bearing.
The suction bell shall have a flared inlet designed to reduce
entrance loss and be provided with flanges to adequately support
the lower bearing and support the weight of the propeller and
SECTION 11391
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