Service Pump Flashcards
What kind of pump is a service pump?
A centrifugal service pump.
- aurora service type of pump
What are 2 types of centrifugal service pumps?
- Buffalo
- Aurora
What kind of service pump on TR JP5 system?
Aurora service pump
The Aurora service pump is a what type of pump?
Double suction, single discharge , centrifugal pump
Specs do the service pump ?
1100 GPM @ 150psi with a 20 ft. Suction lift
What does the service pump consist of ?
- split casing
- wearing rings
- rotating element
Split casing
Casing is horizontally split at the shaft centerline .
- this enables removal of the upper casing half for inspection and maintenance
Split casing is divided into how many chambers ?
3 chambers.
- 2 suction and 1 discharge
How many casings?
- upper half
- lower half
Upper half contains what?
Contains a flange that may connect pump to an air eliminator valve.
How many external seal lines on the upper half casing ?
2 external seal lines
What do the external seal line on the upper half casing do?
Feeds fuel from the discharge chamber to cool the mechanical seals
Lower half casing contains what?
- bearing housing
- suction flange
- discharge flange
- flanges connect pump to the piping system
Drain holes and drain plugs are provided at bottom of both flanges for what?
Draining pump
Centrifugal pumps can be modified to handle fuels at what temperatures?
At all normal temperatures
Wearing rings
There are four replaceable type of wearing rings installed within pump casing.
(2) rotating
(2) stationary
Where are the rotating wearing rings located ?
On the impeller
Where are the stationary wearing rings located ?
Installed within the pump casing between the suction and discharge chambers
Stationary wearing rings are held in place and prevented from rotating how?
By the tongue and groove construction
When pump is assembled the rotating rings ride where?
Inside the stationary rings
Wearing rings serve 2 purposes ?
- Owing to their unique construction and close tolerances, they minimize leakage between suction and discharge chambers
- They allow for the wear created between the impeller and Pump casing .
What happens As fuel passes through the narrow clearances between the wearing rings?
A rapid seal is made by the rapid rotation of the impeller.
After prolonged use of the pump what happens to the wearing rings?
The clearance gradually increases due to wear , sealing effect decreases resulting loss of rated capacity of pump.
Rotating element on service pump consist of
- impeller and pump shaft
- mechanical seals
- bearing cartridges
- falk type - F steel coupling
- magnetic coupling
- Alternate current(AC) magnetic motor controller
Impeller and pump shaft
It is a double - suction , closed impeller. It is keyed and rotates with the pump shaft.
Mechanical seals
They are fitted on the pump shaft protect against fuel leakage from the pump and prevent air from entering the casing around shaft.
2 types of mechanical seals
John crane- single piece unit
Durametallic - 3 piece unit
* must be handled carefully due to some parts being made of carbon
Bearing cartridge
Pump shaft ends are supported by ball bearings encased in bearing cartridges and cradled in the bearing brackets of the lower half casing.
Ball bearings
Absorb radial and axial thrust , and ensure free rotation of the shaft
Single ball bearing
Housed in the inboard bearing cartridge,allowing inboard bearing some axial movement within the bearing cartridge
Dual ball bearings
Housed in the outboard bearing cartridge
Bearing covers
Prevent bearing grease to leak out of the bearing cartridge.
- also prevent dirt , water , or fuel form entering bearing cartridge
Flexible coupling
Designed to absorb vibration due to misalignment between motor shaft and the pump shaft
Coupling hubs
Keyed to both the pump and the motor shafts.. and are lubricated to reduce wear and tear in coupling
Falk type-F steel flex coupling
Flexible , self aligning , grid member coupling.
Magnetic coupling
Used between the pump and the motor.
It consist of a conductor housing and magnetic rotor .
The magnetic attraction between conductor housing and magnetic rotor is translated into rotational torque causing?
The pump shaft to rotate . Lubrication of this coupling is NOT required. And NEVER remove perimeter bolts
AC magnetic controller
Used to control power to the ac motor .
A spring - return start/stop switch and a reset push button are mounted on controller. Also can be stopped by an emergency shutdown switch inside pump room
