Millwright - 2nd Year: Dynamic Pump
Operation Exam Questions and Answers with
Verified Solutions | Latest Updated 2026
What is an impeller? A series of vanes connected to a hub
What is specific speed? A non-dimensional index number equal to
the
speed at which a geometrically similar
impeller has
to operate to deliver 1 gpm of flow against
1 foot of
head
The lower the specific speed, the head per stage
higher the _________________ a
pump can
develop.
A higher specific spped indicates a axial, radial
pump design with head generation
more by __________ forces than
_____________ forces.
Most radial flow impellers use a backwept
________________ vane design.
, What is an open impeller? An impeller with a fully-scalloped or
partially-
scalloped shroud
What is the purpose of the shroud To help stabalize the vane
on an open impeller?
What makes open impellers Cutting edges on the vane tips
suitable
for stringy materials or bulky
solids?
Close axial clearances make open unsuitable
impellers _________________ for
for
abrasive materials.
What is a semi-open impeller? An impeller with a full shroud on the back
that is
not scalloped.
Why does a semi-open impeller It does not have the regenerative action of
develop less head than an open the
impeller? scallop.
The shroud of a semi-open bending
impeller
improves the impellers
___________________
strength.
Operation Exam Questions and Answers with
Verified Solutions | Latest Updated 2026
What is an impeller? A series of vanes connected to a hub
What is specific speed? A non-dimensional index number equal to
the
speed at which a geometrically similar
impeller has
to operate to deliver 1 gpm of flow against
1 foot of
head
The lower the specific speed, the head per stage
higher the _________________ a
pump can
develop.
A higher specific spped indicates a axial, radial
pump design with head generation
more by __________ forces than
_____________ forces.
Most radial flow impellers use a backwept
________________ vane design.
, What is an open impeller? An impeller with a fully-scalloped or
partially-
scalloped shroud
What is the purpose of the shroud To help stabalize the vane
on an open impeller?
What makes open impellers Cutting edges on the vane tips
suitable
for stringy materials or bulky
solids?
Close axial clearances make open unsuitable
impellers _________________ for
for
abrasive materials.
What is a semi-open impeller? An impeller with a full shroud on the back
that is
not scalloped.
Why does a semi-open impeller It does not have the regenerative action of
develop less head than an open the
impeller? scallop.
The shroud of a semi-open bending
impeller
improves the impellers
___________________
strength.
