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Pompa tipleri, pompa uygulamaları ve operasyonları.Denizcilik ve Gemi Mühendisliği Sayfasıhttp://www.facebook.com/gemimuh
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PUMPS
Pumping Basics
Centrifugal Pumps
Positive Displacement Pumps
Pumping BasicsPUMPS deliver energy (lb-ft, lb-in, joules. Etc.) to a given
volume (cu.in., cc. gallon= 231 cu.in., liter= 1000cc) Pressure is usually thought of as force/area, but is also energy/volume
(lb-in/in3 = lb/in2 or psi) Pressure x Flow is power: energy/vol x vol/time PSI x GPM = HP; Pascals x m3/sec = watts 1714
Energy Gain (ib-in)per unit volume (in3)
= lb/in2 (psi)
Pumping Basics HEAD, energy per pound of liquid, commonly expressed in feet representing the
vertical height of a static column of liquid corresponding to the pressure of the fluid at the point in question
In general, a liquid may have three kinds of energy. That is, the capacity to do work may be due to three factors: Potential Head - (energy of position, i.e. the work obtainable in dropping a
vertical distance) Hz is directly measured in feet Static Pressure Head - (energy per pound due to pressure, i.e. the height to
which a liquid can be raised by a given pressure) Hp(ft) = [PSI x 2.31] / SG Velocity Head - (kinetic energy per pound, i.e. the vertical distance a liquid
would have to fall to acquire velocity V) Hv(ft) = V2 / 2g
P 1 psi P 1 psi P 1 psi
2.31 ft
H2OSG= 1
GasolineSG= 0.7
MolassesSG= 1.5
1.54 ft
3.3 ft
VelocityV
HV= V2
2g
P
Pumping Basics Total Pump Head, is the difference between the energy per lb
on the discharge side vs. the suction side of a pump (expressed in feet) Zs & Zd are the elevation (ft) to the point of suction or discharge measure
from thr datum plane (usually through the center of the pump’s inlet port) Hfs & Hfd are the friction losses (in feet) in the direction of flow to/from the
pump suction & discharge parts to the respective measuring points
H= ( Pd – Ps ) x 2.31/SG
+ ( Zd – Zs )+ ( Vd2 – Vs2 )
2 g+ ( Hfd – Hfs )
P
Ps
Pd
Vs Zs
Zd
Vd
Hfs
Hfd
Pump Types
Kinetic vs. Positive Displacement
Centrifugal vs. Special Effect e.g., Jet Pump (Eductor)
Radial vs. Axial vs. Mixed Flow
Centrifugal (Radial Flow)IMPELLER
EYE
VOLUTE
DISCHARGE
SUCTION
(Radial) Centrifugal Pump Varieties
Impeller construction Horizontal vs. Vertical
Closed Impeller
Semi-closed Impeller
Open Impeller
(Radial) Centrifugal Pump Varieties Single suction
Multi-stage centrifugal pumps
Double suction
P
Centrifugal Pump Characteristics
FLOW (GPM)
PRESSURE (PSI)
IDEAL
ACTUAL
PUMP CHARACTERISTIC
SYSTEM CHARACTERISTIC
SHUT-OFF HEAD (no flow)
OPERATING POINT
PUMPSYSTEM
P
Centrifugal Pump Characteristics
FLOW (GPM)
PRESSURE (PSI)
IDEAL
ACTUAL
PUMP CHARACTERISTIC
SYSTEM CHARACTERISTIC
SHUT-OFF HEAD (no flow)
OPERATING POINT
PUMPSYSTEM
PUMP CHARACTERISTIC (higher RPM)
SHUT-OFF HEAD (no flow) PUMP CHARACTERISTIC
(lower RPM)
Pump TypesKinetic vs. Positive Displacement
Reciprocating vs. Rotary
Fixed volume pushed through each stroke (recip) or revolution (rotary)
P
Pos. Displ. Pump Characteristics
FLOW (GPM)
PRESSURE (PSI)
IDEALACTUAL
PUMP CHARACTERISTIC
SYSTEM CHARACTERISTIC
OPERATING POINT
PUMPSYSTEM
Pos. Displ. Pump Characteristics
FLOW (GPM)
PRESSURE (PSI)
IDEALPUMP
SYSTEMACTUAL
P
?
Relief Valve
Relief Valve setting
Through Pump
Into System RecircRecirc
Pos. Displ. Pump Characteristics
FLOW (GPM)
PRESSURE (PSI)
IDEALPUMP
SYSTEMACTUAL
P
Relief Valve
Relief Valve setting
Through Pump
Recirc
Increase Pump Speed
Reciprocating Pumps Double acting Single acting
one cycle
one volone vol
one cycle
one volone voltwo volstwo vols
GPM= VOL(gal) x CYCLE/MIN GPM= 2 x VOL(gal) x CYCLE/MIN
single or double actinghorizontal or vertical
Reciprocating Pumps Simplex (one piston) Duplex
Steam End Liquid End
Slide Valve Valve Chest
single or double actinghorizontal or vertical
Triplex & Multiplex
Motor or Engine driven
Multiple (3 or more) plungers (pistons)
single or double actinghorizontal or vertical
Reciprocating Pumps Diaphragm Pump (air operatated)
DISCHARGE
SUCTION
SHUTTLE VALVE
AIR SUPPLY
EXHAUST
Rotary PumpsGear Pump (external gear)
(Internal) Gear Pump
= volume betw adj teeth
in3 x # teeth x 2 gears x RPM231 in3/gal
= GPM
Driving Gear
Driven Gear
Driving Gear
Driven Gear
Rotary Pumps Gear Pumps Lobe Pumps
One rotor does not drive the other
Timing Gears required
Two, three, or more lobes possible:2 lobes = “rotating piston”
Rotary Pumps Gear Pumps Lobe Pumps Screw Pumps
Double-screwDouble-endwith Timing Gears
Triple-screwDouble-endwithout Timing Gears
Double-screwSingle-endwithout Timing Gears
Rotary Pumps Gear Pumps Lobe Pumps Screw Pumps Sliding Vane Pumps
Rotary Pumps Gear Pumps Lobe Pumps Screw Pumps Sliding Vane Pumps Liquid Piston Pump
Circulated water acts as piston
Air drawn in to create vacuum
Used to prime centrifugal pump
Pumping OperationsStarting Procedures
Securing Procedures
Sytem Operation
General Considerations
• Insure that suction side piping is lined up as intended. All suction connections should be checked to prevent drawing from some unintended location.
• Insure that discharge piping is lined up as intended. All discharge connections should be checked to prevent inadvertent discharge to an unintended space or overboard.
• Be familiar with normal operating parameters (pressures, temperatures, etc.) so that abnormalities may be detected promptly.
Centrifugal Pumps
Rotary (P.D.) Pumps
Steam Recip. PumpsSUPPLYSUPPLY
EXHAUSTEXHAUST
DISCHARGEDISCHARGE
SUCTIONSUCTION
STEAM END
LIQUID END
Turbine Feed Pumps
SUPPLYSUPPLY
EXHAUSTEXHAUST
DISCHARGEDISCHARGE
SUCTIONSUCTION
PRESS PRESS REG V.REG V.
RECIRCRECIRCDRAINDRAIN
L.O. SYSTEML.O. SYSTEM
Turbine Feed Pumps
DRAINDRAIN
DISCHARGEDISCHARGE
SUPPLYSUPPLY
EXHAUSTEXHAUSTSUCTIONSUCTION
PRESS PRESS REG V.REG V.
SUCTIONSUCTION
MAINMAIN AUXAUX
RECIRCRECIRCL.O. L.O. PUMPPUMP
O/S O/S TRIPTRIP
Turbine Feed Pumps
SUPPLYSUPPLY
PRESS PRESS REG V.REG V.
SUCTIONSUCTION EXHAUSTEXHAUST
DISCHARGEDISCHARGE
RECIRCRECIRCDRAINDRAIN
L.O. SYSTEML.O. SYSTEM
Turbine Feed PumpsSUPPLYSUPPLY
PRESS PRESS REG V.REG V.
L.O. supply
Fd. Pump discharge pressure
L.O. return
PILOT PILOT VALVEVALVE
OPERATING OPERATING CYLINDERCYLINDER
Press incr
Press decr
… or relax spring
… or tighten spring
Reach rod
Operating piston drops decreasing steam flow
Operating piston rises increasing steam flow
With spring tension & pump pressure balanced, steam flow is constantOverspeed trip drops operating piston & shuts off steam flow
O/S Trip
Piping systems• Example 1: (Generic) Fuel oil Transfer
Piping systems• Fuel oil Transfer Manifold
SUCTION
FILL
Piping systems• Example 1: (Generic) Fuel oil Transfer
Piping systems• Example 1: (Generic) Fuel oil Transfer
Piping systems• Example 2: Bilge, Ballast, Fire Main
SEA CHESTS
Piping systems• Bilge Manifolds Ballast Manifolds
Low pressure in upper chamber draws bilge water up
Stop-check prevents bilge flooding
Ballasting or deballasting possible
Piping systems• Example 2: Bilge, Ballast, Fire Main