Tpc 344 Flashcards
How can water pressure be expressed?
Psi, or head pressure
The available NPSH of a system must be…
Equal to or greater than the required NPSH of the pump
The formation of vapor pockets or bubbles in a liquid is called?
Cavitation
What is the horsepower required to drive a pump called?
Brake horsepower
1 electrical horsepower is equal to how many watts?
746 watts
The area that surrounds and houses the packing is called?
The stuffing box
For four or more rings each joint should be how far apart from the proceeding joint?
90 degrees
The most common mechanical seal configuration is the?
Single internal seal
In some mechanical seals, the rotating element is secured to the shaft by a flexible rubber material called?
A boot
Friction is the major cause of burned seals, friction is the result of…
Improper lubrication
When grouting the baseplate how long should you allow the grout to set for?
At least 48 hours
When you tighten the hold down fasteners a certain amount of spring will be created, how can you remove spring?
Place a dial indicator on one foot
What is bearing end play?
Axial movement of the shaft
Cavitation is a phenomenon caused by?
A pressure loss in the suction line of a pump system
What is ring seizure?
Loss of clearance between the rings
If both bearings are on the same side you the impeller the one nearest the impeller is called?
The inboard bearing
What is the most common sign of cavitation?
Pitting, small holes or indentations on the back sides of the impeller vanes
The runout reading should not exceed how many thousandths?
.003
Too much clearance between the two sets of rings will cause…
Leakage of fluid back into the suction side of the pump
When installing a gasket you may wish to…
Shellac the lower half of the casing
What are the most commonly used type of all rotary pumps?
External gear pumps
What keeps the sliding vanes in contact with this inner surface
Centrifugal force
How long should a riser be?
A riser should be about 5 times as long as the diameter of the pipe
In most rotary pumps what is used to lubricate the bearings supporting the shaft?
The fluid being handled by the pump
If a pump is not delivering fluid at the discharge side what is the first thing you do?
Stop the pump at once
