maintenance and repair.
**************************************************************************
In general, each pumping unit includes a pump/motor, discharge tube,
[discharge elbow], air vent, [lifting chain], cable, and controls. Each
pump shall be of the vertical, axial or mixed-flow submersible type for
[storm water] [flood control] [attached to the same shaft with a
submersible electric motor] [direct coupled through a reducing gear to a
submersible motor]. The pump/motor shall be electrically operated and
installed in a discharge tube. Except as otherwise stated or noted, the
terms pump and pump/motor both refer to a pump/motor integral unit.
1.4.3
General Design Requirements
a. The pump shall meet head, capacity, speed, efficiency, pump sump
design, range of operation, cavitation, and vibration requirements as
specified. [The Contractor may utilize reduction gears or adjustable
impeller blades to meet the specification performance requirements.]
b. The pump shall be designed for runaway speed as calculated by the
Contractor for the system shown and specified. Waterhammer
calculations shall be included when long discharge lines exist. The
reverse speed shall be calculated assuming power failure and discharge
valves fail to close.
c. The pump shall, as a minimum, meet the applicable design,
materials, and manufacture requirements of HI 1.1-1.4, HI 2.1-2.4, HI
9.1-9.5 and these specifications.
d. The pumping unit design and performance shall have been
demonstrated by previous successful operation of pumps of the required
type and of equal design complexity by the manufacturer.
e. The pump shall operate in a discharge tube. The discharge tube
shall fit within the dimensions shown so that installation and
maintenance can be carried out by an [overhead bridge] [jib] [mobile]
crane. The weight of the pump/motor integral unit shall not exceed
[_____] kg lb.
f. The pump shall be designed for the calculated hydraulic pressure
including waterhammer to which the pump parts are exposed.
g. The pump losses, as calculated by the Contractor, are in addition
to the specified head and shall be allowed for when computing the pump
system output.
h. The pump shall have a continuously rising head characteristic with
decreasing capacity over the required range of operation specified.
The pump shall not have an unstable operating characteristic over the
required range of operation.
i. The pump shall meet all requirements for net positive suction head
required (NPSHR) and operate without surging.
j. Associated pumping equipment including, but not limited to,
electrical controls, instrumentation, [and pump control center] shall
be suitable for [indoor] [outdoor] operation.
SECTION 15132A
Page 12
Previous Page
