Pumps 1 Flashcards
Definition of a pump?
Mechanical device that transfers liquids against gravity or exhausts gases.
What is pump capacity?
The amount of material that a pump moves in a given amount of time.
What are the three things that determine pump capacity?
Size of pump. How fast motor is turning pump in RPM. The viscosity of the fluid.
How do you measure flow?
GPM
Definition of pressure?
Force per unit area.
Define Head.
Hight of a column of fluid.
What is positive head? (Suction head)
Positive Pressure on inlet side of pump caused by head.
What is negative head? (Suction lift)
Distance liquid must be lifted to the inlet of pump caused by less than atmospheric pressure.
Pressure at the discharge of pump is what?
Discharge head.
Total distance a pump can lift the liquid is considered?
Total head.
Centrifugal pumps have to be what I’m order to work?
Primed the can not pump air.
Limitation to single impellers?
Pressure. Once they are at 80-90 psi they will stall At discharge.
Multi stage impellers help with what?
Can build more pressure at the discharge of pump.
Three types of impellers?
Open, semi-open, enclosed.
Two designs of pump cases?
Split case, insuction design.
Two bearing configurations for pumps?
Between bearing = split case design.
Over hung = endsuction design.
Two types of packing for pump?
Compression packing.
Mechanical seal.
Four things needed to pack pumps with compression packing?
Stuffing box
Packing rings
Lantern ring
Glad follower
What do you have to do when inserting the packing rings?
Stagger the joints.
Two ways to attach driver to pump? (Mounting styles)
Frame mount / c frame mount
Close coupled ( share the same shaft )
What are three things flush water does?
Flush away contaminants
Cools shaft
Cooks packing
Two sources of flush water?
External source
The process water itself
What is pump cavitation?
Collapse and formation of air bubbles.
