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MARINE PUMPING SYSTEM

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Title: MARINE PUMPING SYSTEM


1
MARINE PUMPING SYSTEM
2
SPECIFIC LEARNING OBJECTIVES
  • At the end of this topic you are expected to
    learn
  • Principles of Marine Pumping Systems
  • State the function of a pump
  • Describe the three requirements for a pump to
    transfer fluids
  • List the losses of head in a pumping system
  • Explain the requirement for viscosity of the
    fluid for pump design

3
  • Explain the requirement for permission before any
    fluid is transferred onboard

4
  • Pumping System have two main purposes
  • Transfer of liquid from one place to another
    place (e.g. water from an underground aquifer
    into a water storage tank)
  • Circulate liquid around a system (e.g. cooling
    water or lubricants through machines and
    equipment)

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10
PUMP
  • A pump is a device used to move fluids, such as
    liquids, gases or slurries.
  • A pump displaces a volume by physical or
    mechanical action. Pumps fall into three major
    groups direct lift, displacement, and gravity
    pumps.1 Their names describe the method for
    moving a fluid.

11
PUMP
  • Defn device that uses an external power source
    to apply force to a fluid in order to move it
    from one place to another
  • Must overcome
  • (1) frictional forces from large quantities of
    fluid
  • (2) difference in static pressure between two
    locations
  • Must provide any velocity desired

12
MARINE PUMP
  • A device use aboardship which adds energy to a
    liquid or gas to overcome resistance or system
    losses causing it to generate pressure and
    perhaps movement of a fluid
  • A machine used to raise fluid from a low point to
    a high point

13
  • Engine a device for converting thermal energy
    of working substance into useful mechanical work
  • Marine pumps generally handle fuel oil,
    lubricating oil, condensate and boiler feed,
    circulation water or coolant, ballast and bilge
    water, air, etc. though pumps delivering air are
    generally called blowers or compressors.
  • Special liquid cargoes of nearly or any sort may
    be handled by a suitable pump. Depending upon the
    types of installation, pumps are driven by steam
    engines, steam, electric motors, Diesel engines
    and air.

14
  • Pumps can also be found coupled with engine it
    supports. Motive power is selected for reasons of
    safety, economics or convenience.

15
Fluid Properties
  • The properties of the fluids being pumped can
    significantly affect the choice of pump. Key
    considerations include
  • Acidity/alkalinity (pH) and chemical composition.
    Corrosive and acidic fluids can degrade pumps,
    and should be considered when selecting pump
    materials.
  • Operating temperature. Pump materials and
    expansion, mechanical seal components, and
    packing materials need to be considered with
    pumped fluids that are hotter than 200F.
  • Solids concentrations/particle sizes. When
    pumping abrasive liquids such as industrial
    slurries, selecting a pump that will not clog or
    fail prematurely depends on particle size,
    hardness, and the volumetric percentage of
    solids.

16
Fluid Properties
  • Specific gravity. The fluid specific gravity is
    the ratio of the fluid density to that of water
    under specified conditions. Specific gravity
    affects the energy required to lift and move the
    fluid, and must be considered when determining
    pump power requirements.
  • Vapor pressure. A fluids vapor pressure is the
    force per unit area that a fluid exerts in an
    effort to change phase from a liquid to a vapor,
    and depends on the fluids chemical and physical
    properties. Proper consideration of the fluids
    vapor pressure will help to minimize the risk of
    cavitation.

17
Fluid Properties
  • Viscosity. The viscosity of a fluid is a measure
    of its resistance to motion. Since kinematic
    viscosity normally varies directly with
    temperature, the pumping system designer must
    know the viscosity of the fluid at the lowest
    anticipated pumping temperature. High viscosity
    fluids result in reduced centrifugal pump
    performance and increased power requirements. It
    is particularly important to consider pump
    suction-side line losses when pumping viscous
    fluids.

18
3 REQUIREMENTS OF A PUMP TO TRANSFER FLUID
  • A marine pumping system on a ship consists of
  • Suction piping
  • Pump
  • Discharge piping
  • The system is arranged to provide a positive
    pressure or head at some point and discharge the
    liquid. The pump provides the energy to develop
    the head and overcome any losses in the system.
  • The rate of flow at a certain head is called duty
    point.

19
PUMP HEAD
  • Head is a measure of resistance to flow. If a
    pump has a maximum output of 20 head feet, it
    means it can pump water 20' straight in the air.
    If a pump is rated at 50 gallons per minute at 10
    feet it means it can overcome 10 feet of head
    (TDH) and still deliver 50 GPM. As you increase
    the head, you decrease the flow rate, and
    increase your operating costs. To maximize your
    flow, you must minimize your head, which also
    minimizes your operating costs.

20
3 MAIN SOURCES OF HEAD
  1. Static Head - This is the vertical distance you
    raise the water. To determine your static head,
    measure from the surface of the tank
    (vertically), to the highest point in the
    discharge line where the water is discharged to
    the atmosphere.

21
3 MAIN SOURCES OF HEAD
  1. Friction Head - As water flows through pipe and
    fittings there is resistance. The higher the flow
    and/or the smaller the pipe, the higher the
    resistance. Determine your overall pipe length,
    including adding in the equivalent length for
    your fittings. Consult the friction loss chart.
    Find where the column for your pipe diameter
    intersects the row for your flow rate and read
    the friction loss per 100' pipe. Use large enough
    pipe to minimize friction loss. It is usually
    best to keep your friction loss (per 100 feet of
    pipe) to less than 6 feet. In other words, once
    you know the desired flow rate, pick a pipe
    diameter, or schedule, that will give you less
    than 6 feet of friction loss per 100 feet of
    pipe. (Friction Loss and Fittings Loss)

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23
3 MAIN SOURCES OF HEAD
  • Pressure Head - Any additional pressure required
    by filters, spray nozzles, etc. must be
    calculated. The conversion is 1 PSI 2.31 head
    feet.
  • - Atmospheric pressure usually refers to the
    pressure in the local environment of the pump.
    Atmospheric pressure varies with elevation, it is
    14.7 psi at sea level and decreases with rising
    elevation.
  • If our filter runs at 10 PSI, that would add
    23.1 feet of head to the 17.9 feet required to
    overcome the friction loss of our pipe and
    fittings. So now the total pump head is 41 feet
    without considering the static head. (Notice that
    the pump head will increase as the filter gets
    dirty and increases the back pressure.)

24
3 MAIN SOURCES OF HEAD
  1. Total dynamic head ( TDH) Sum of static head,
    friction loss head, fittings loss head, and
    pressure head.

Type of head Source Calculation PH in Feet
Static Head Elevated Pipe 10' - above surface of water 10.0
Pipe Loss 2" Pipe 8.12' per 100 feet of pipe 13.0
Fittings Loss 6' per elbow 10x 2" 90 elbows 60 ft 4.9
Pressure Head Filter running at 10 psi x 2.31 23.1
Total Pump head in feet Total Pump head in feet Total Pump head in feet 51.0
25
3 MAIN SOURCES OF HEAD
  • Don't forget to add up the equivalent feet of
    pipe for all the fittings. Now that you know your
    flow and head, you can select a pump that
    provides this performance, and does so
    efficiently.

26
Losses of Head in Pumping System
  • Power supplied to the pump must take into account
    the various losses. These are made up of
  • Friction Loss in bearings and glands, surfaces of
    impeller and casing. Impellers should be highly
    polished to minimize friction loss.
  • Head Loss in pump due to shock at each entry and
    exit to impeller vane where eddies are formed at
    vane edges.
  • Leakage loss in thrust balance devices, gland
    sealing, clearances between cutwater and casing
    and bearing seals.

27
Requirement for Viscosity of the Fluid for Pump
  • Viscosity - the property of a fluid or semifluid
    that causes it to resist flowing
  • Oil are much more difficult for pumps to handle
    than water. Losses increase within the pump and
    pump lines. Both head and capacity are reduced
    therefore more power is required for operation.
  • Both hot and thick liquids should flow to the
    pump under a positive suction head (flow by
    gravity) for satisfactory operation. The pump
    will then be kept properly primed in the case of
    thick liquids vaporization and vapour binding
    will be avoided in the case of hot liquids.

28
Requirement for Viscosity of the Fluid for Pump
  • The problem of lifting a hot liquid is often
    difficult. The hotter the liquid, the lower will
    be the maximum possible suction lift. Water boils
    at 100 C atmospheric pressure. Under the partial
    vacuum that exists in the feed pipe, the boiling
    point is lower. Part of the hot water may
    vaporize causing vapour binding in the pump. In
    some cases the water vaporizes and expands
    sufficiently to destroy the vacuum thereby, stops
    the effectiveness of pumping.

29
Requirement for Viscosity of the Fluid for Pump
  • When pumping hot oil, it may happen that a small
    amount of water entrained in the oil may flash
    (boil) and interrupt the pumping operation. This
    can be serious in the case of a fuel oil service
    pump, as it may cause a flare back from the
    boilers. Providing an air chamber on the
    discharge line which will maintain a pressure
    while the pump is compressing the vapour in the
    line, can guard this against other precautions
    may be taken.

30
Requirement for Viscosity of the Fluid for Pump
  • Here is what is going to change when you pump
    viscous fluids with a centrifugal pump
  • The brake horsepower requirement will increase.
  • You will notice a reduction in the head the pump
    will produce.
  • Some reduction in capacity will occur with
    moderate and high viscosities.
  • The pump's efficiency will decrease.

31
Requirement for Viscosity of the Fluid for Pump
  • High viscosity fluids are better handled with
    positive displacement pumps that are affected
    differently than centrifugal pumps by a change in
    fluid viscosity
  • At a constant speed, changes in viscosity will
    have very little affect on capacity.
  • The total head will probably increase with
    viscosity because of higher system resistance.
  • The brake horsepower (kilowatts) will increase
    with capacity.
  • The efficiency probably will not be affected
    because of less leakage through the internal pump
    clearances. In some cases the efficiency will
    increase

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34
Pre-Bunker Checklist
  • Pre-Bunkering Procedure
  • 1. State of adjacent waters noticed
  • 2. Vessel properly secured to dock
  • 3. Check suppliers product corresponds to ordered
    product
  • 4. Agree quantity to be supplied
  • 5. Check valves open
  • 6. Day tanks full and supply valves closed
  • 7. Warning signs in position e.g. No Smoking
  • 8. SOPEP plan available

35
  • 9. Clean up material in place
  • 10. Oil Boom in place
  • 11. Foam fire extinguisher placed at bunker
    station
  • 12. Alfa Laval and transfer pumps off
  • 13. Fuel tank supply valves open
  • 14. Agree stop/start signals between vessel and
    barge/truck
  • 15. Bravo flag flying/red light showing
  • 16. Agree pumping/transfer rate
  • 17. Agree emergency shut down procedure
  • 18. Specification sheet received

36
  • 19. Check hose and couplings are secure and in
    good order
  • 20. Fuel nozzle and hose secured to vessel
  • 21. Check barge/truck meters Reading
  • 22. Check on board meters Reading
  • 23. Bunker Valve open
  • 24. Unused manifold connections blanked off
  • 25. Master informed
  • 26. Signal pumping to commence
  • The above checklist has to be completely filled
    legibly by both the ship barge personnels.

37
SOPEP equipments
  • At the bunker manifold and wherever necessary, as
    per the ships SOPEP plan, the SOPEP equipments
    should be kept in immediate readiness in order to
    avoid oil spill/pollution during bunkering
    operation.

38
SOPEP- Shipboard Oil Pollution Emergency Plan.
  • SOPEP- Shipboard Oil Pollution Emergency Plan.
  • The SOPEP Locker must have minimum of the below
    specified items
  • 1. absorbent roll
  • 2. absorbent pads
  • 3. absorbent granules
  • 4. absorbent materials
  • 5. brooms
  • 6. shovels
  • 7. mops
  • 8. scoops
  • 9. empty receptacles (200 ltrs capacity)
  • 10. portable air driven pumps
  • 11. oil boom
  • 12. oil spill dispersants.

39
During Bunkering Procedures
  • During Bunkering checklist
  • 1. Witness taking and sealing of 2 representative
    product samples
  • 2. Monitor fuel connections for leaks fuel flow
    and control tank levels
  • 3. Change over of tanks whenever necessary.
  • 4. Checking the rate at which bunkers are
    received.
  • 5. Checking the tightness/slackness of mooring
    ropes.
  • 6. Checking trim/list of the bunker barge the
    ship.
  • 7. Continuous monitoring/look outs for the
    vessel's position(when at anchor).
  • During bunkering, the above checklist must be
    filled up and continuous monitoring of the above
    specified items are required till the bunkering
    operation is complete.

40
After Bunkering Procedures
  • On completion of the bunkering operations, with
    the ship-barge co-ordination, the line should be
    blown with air to make sure the line is not
    filled with oil. The after-bunker checklist is
    followed.
  • After Bunker Checklist
  • 1. Bunker Valve closed
  • 2. Disconnect hose (drain before disconnecting)
  • 3. Check barge/truck meter Reading
  • 4. Check ships meter Reading

41
  • 5. Sign Bunker Delivery Receipt BDR No.(Bunker
    Delivery Report/Note).
  • 6. Retain BDR with product sample
  • 7. SOPEP plan returned to bridge
  • 8. Clean up gear stowed / Oil boom returned
  • 9. Bravo Flag/Red light stowed/switched off
  • 10. Remove and pack away warning/safety signs
  • 11. Foam fire extinguisher placed back in correct
    location
  • 12. Complete Oil Record Book
  • 13. Master informed of completion
  • 14. Confirm in Oil Record Book Bunkering
    checklist completed

42
END OF PRESENTATION
43
Glossary in Pumps and Pumping System
  • Fluid - any substance that undergoes a change in
    pressure, temperature or volume used as means to
    carry out a thermodynamic process or cycle
  • Cavitation the collapse of bubbles that are
    formed in the eye of the impeller due to low
    pressure. The implosion of the bubbles on the
    inside of the vanes creates pitting and erosion
    that damages the impeller. The design of the
    pump, the pressure and temperature of the liquid
    that enters the pump suction determines whether
    the fluid will cavitate or not.

44
Glossary in Pumps and Pumping System
  • Centrifugal force A force associated with a
    rotating body. In the case of a pump, the
    rotating impeller pushes fluid on the back of the
    impeller blade, imparting circular and radial
    motion. A body that moves in a circular path has
    a centrifugal force associated with it .
  • Dead head a situation that occurs when the
    pump's discharge is closed either due to a
    blocage in the line or an inadvertently closed
    valve. At this point, the pump will go to it's
    maximum shut-off head, the fluid will be
    recirculated within the pump resulting in
    overheating and possible damage.
  • Diffuser located in the discharge area of the
    pump, the diffuser is a set of fixed vanes often
    an integral part of the casing that reduces
    turbulence by promoting a more gradual reduction
    in velocity.

45
Glossary in Pumps and Pumping System
  • Efficiency the efficiency of a pump can be
    determined by measuring the torque at the pump
    shaft with a torque meter and then calculating
    the efficiency based on the speed of the pump,
    the pressure or total head and flow produced by
    the pump. The standard equation for torque and
    speed provides power.
  • Absolute pressure pressure is measured in psi
    (pounds per square inch) in the imperial system
    and kPa (kiloPascal or bar) in the metric system.
    Most pressure measurements are made relative to
    the local atmospheric pressure. In that case we
    add a "g" to the pressure measurement unit such
    as psig or kPag. The value of the local
    atmospheric pressure varies with elevation.

46
Glossary in Pumps and Pumping System
  • It is not the same if you are at sea level (14.7
    psia) or at 4000 feet elevation (12.7 psia). In
    certain cases it is necessary to measure pressure
    values that are less then the local atmospheric
    pressure and in those cases we use the absolute
    unit of pressure, the psia or kPa a.
  • pa(psia) pr(psig) patm(psia), patm 14.7
    psia at sea level.
  • where pa is the absolute pressure, pr the
    relative pressure and patm the absolute pressure
    value of the local atmospheric pressure.

47
Glossary in Pumps and Pumping System
  • Accumulator used in domestic water applications
    to stabilize the pressure in the system and avoid
    the pump cycling on and off every time a tap is
    opened somewhere in the house.
  • Affinity laws the affinity laws are used to
    predict the change in diameter required to
    increase the flow or total head of a pump. They
    can also predict the change in speed required to
    achieve a different flow and total head. The
    affinity laws can only be applied in
    circumstances where the system has a high
    friction head compared to the static head and
    this is because the affinity laws can only be
    applied between performance points that are at
    the same efficiency.
  • Axial flow pump refers to a design of a
    centrifugal pump for high flow and low head. The
    impeller shape is similar to a propeller. The
    value of the specific speed number will provide
    an indication whether an axial flow pump design
    is suitable for your application

48
Glossary in Pumps and Pumping System
  • Baseplate all pumps require some sort of steel
    base that holds the pump and motor and is
    anchored to a concrete base.
  • Best Efficiency Point (B.E.P.) The point on a
    pump's performance curve that corresponds to the
    highest efficiency. At this point, the impeller
    is subjected to minimum radial force promoting a
    smooth operation with low vibration and noise.
  • Bingham plastic A fluid that behaves in a
    Newtonian fashion (i.e. constant viscosity) but
    requires a certain level of stress to set it in
    motion.
  • Bourdon pressure gauge the Bourdon tube is a
    sealed tube that deflects in response to applied
    pressure and is the most common type of pressure
    sensing mechanism.

49
Glossary in Pumps and Pumping System
  • Check valve a device for preventing flow in the
    reverse direction. The pump should not be allowed
    to turn in the reverse direction as damage and
    spillage may occur. Check valves are not used in
    certain applications where the fluid contains
    solids such as pulp suspensions or slurries as
    the check valve tends to jam. A check valve with
    a rapid closing feature is also used as a
    preventative for water hammer.
  • Chopper pump a pump with a serrated impeller
    edge which can cut large solids and prevent
    clogging.
  • Closed or open impeller the impeller vanes are
    sandwiched within a shroud which keeps the fluid
    in contact with the impeller vanes at all times.
    This type of impeller is more efficient than an
    open type impeller. The disadvantage is that the
    fluid passages are narrower and could get plugged
    if the fluid contains impurities or solids.

50
Glossary in Pumps and Pumping System
  • CV coefficient a coefficient developed by
    control valve manufacturers that provides an
    indication of how much flow the valve can handle
    for a 1 psi pressure drop. For example, a control
    valve that has a CV of 500 will be able to pass
    500 gpm with a pressure drop of 1 psi. CV
    coefficients are sometimes used for other devices
    such as check valves.
  • Cutwater the narrow space between the impeller
    and the casing in the discharge area of the
    casing.
  • Diaphragm pump a positive displacement pump.
    Double Diaphragm pumps offer smooth flow,
    reliable operation, and the ability to pump a
    wide variety of viscous, chemically aggressive,
    abrasive and impure liquids. They are used in
    many industries such as mining, petro-chemical,
    pulp and paper and others.

51
Glossary in Pumps and Pumping System
  • Dilatant The property of a fluid whose viscosity
    increases with strain or displacement.
  • Double suction pump the liquid is channeled
    inside the pump casing to both sides of the
    impeller. This provides a very stable hydraulic
    performance because the hydraulic forces are
    balanced. The impeller sits in the middle of the
    shaft which is supported on each end by a bearing
  • Double volute pump a pump where the immediate
    volute of the impeller is separated by a
    partition from the main body of the casing. This
    design reduces the radial load on the impeller
    making the pump run smoother and vibration free.

52
Glossary in Pumps and Pumping System
  • Drooping curve similar to the normal profile
    except at the low flow end where the head rises
    then drops as it gets to the shut-off head point.
  • End suction pump a typical centrifugal pump, the
    workhorse of industry. Also known as volute pump,
    standard pump, horizontal suction pump. The back
    pull out design is a standard feature and allows
    easy removal of the impeller and shaft with the
    complete drive and bearing assembly while keeping
    the piping and motor in place.
  • Expeller a hydro-dynamic seal that provides a
    seal without addition of water to the gland,
    specially useful for liquid slurries.

53
Glossary in Pumps and Pumping System
  • External Gear pump a positive displacement pump.
    Two spur gears are housed in one casing with
    close clearance. Liquid is trapped between the
    gear tooth spaces and the casing, the rotation of
    the gears pumps the liquid. They are also used
    for high pressure industrial transfer and
    metering applications on clean, filtered,
    lubricating fluids.
  • Foot valve a check valve that is put on the end
    of the pump suction pipe, often accompanied with
    an integrated strainer.
  • Head the height at which a pump can displace a
    liquid to. Head is also a form of energy. In pump
    systems there are 4 different types of head
    elevation head or static head, pressure head,
    velocity head and friction head loss.

54
Glossary in Pumps and Pumping System
  • Hydraulic gradient All the energy terms of the
    system ( for example velocity head and piping and
    fitting friction loss) are converted to head and
    graphed above an elevation drawing of the
    installation. It helps to visualize where all the
    energy terms are located and ensure that nothing
    is missed.
  • Impeller The rotating element of a pump which
    consists of a disk with curved vanes. The
    impeller imparts movement and pressure to the
    fluid.
  • Impeller eye that area of the centrifugal pump
    that channels fluid into the vane area of the
    impeller. The diameter of the eye will control
    how much fluid can get into the pump at a given
    flow rate without causing excessive pressure drop
    and cavitation.

55
Glossary in Pumps and Pumping System
  • Hydraulic gradient All the energy terms of the
    system ( for example velocity head and piping and
    fitting friction loss) are converted to head and
    graphed above an elevation drawing of the
    installation. It helps to visualize where all the
    energy terms are located and ensure that nothing
    is missed.
  • Impeller The rotating element of a pump which
    consists of a disk with curved vanes. The
    impeller imparts movement and pressure to the
    fluid.
  • Impeller eye that area of the centrifugal pump
    that channels fluid into the vane area of the
    impeller. The diameter of the eye will control
    how much fluid can get into the pump at a given
    flow rate without causing excessive pressure drop
    and cavitation.

56
Glossary in Pumps and Pumping System
  • Inducer an inducer is a device attached to the
    impeller eye that is usually shaped like a screw
    that helps increase the pressure at the impeller
    vane entrance and make viscous or liquids with
    high solids pumpable.
  • Internal gear pump a positive displacement pump
    invented by Jens Nielsen, one of the founders of
    Viking Pump. It uses two rotating gears which
    un-mesh at the suction side of the pump to create
    voids which allow atmospheric pressure to force
    fluid into the pump. The spaces between the gear
    teeth transport the fluid on either side of a
    crescent to the discharge side, and then the
    gears re-mesh to discharge the fluid.

57
Glossary in Pumps and Pumping System
  • Jet pump a jet pump is a commonly available
    residential water supply pump. It has an
    interesting clever design that can lift water
    from a well (up to 25 feet) and allow it to
    function without a check valve on the suction and
    furthermore does not require priming. The heart
    of the design is a venturi (source of water is
    from the discharge side of the impeller) that
    creates low pressure providing a vacuum at the
    suction and allowing the pump to lift fluids.
  • Laminar A distinct flow regime that occurs at
    low Reynolds number (Re lt2000). It is
    characterized by fluid particles in layers moving
    past one another without mixing.

58
Glossary in Pumps and Pumping System
  • Lobe pump a positive displacement pump.
    Primarily used in food applications because they
    handle solids without damaging them. Lobes are
    driven by external timing gears as a result the
    lobes do not make contact. Liquid travels around
    the interior of the casing in the pockets between
    the lobes and the casing, meshing of the lobes
    forces liquid through the outlet port under
    pressure.
  • Mechanical seal a name for the joint that seals
    the fluid in the pump stopping it from coming out
    at the joint between the casing and the pump
    shaft.
  • Net Positive Suction Head Available (N.P.S.H.A.)
    Net positive suction head available. The head or
    specific energy at the pump suction flange less
    the vapor pressure head of the fluid.

59
Glossary in Pumps and Pumping System
  • Net Positive Suction Head Required (N.P.S.H.R.)
    Net positive suction head required. The
    manufacturers estimate on the NPSH required for
    the pump at a specific flow, total head, speed
    and impeller diameter. This is determined my
    measurement.
  • Newtonian fluid A fluid whose viscosity is
    constant and independent of the rate of shear
    (strain). For Newtonian fluids, there is a linear
    relationship between the rate of shear and the
    tangential stress between layers.
  • Operating point The point (flow rate and total
    head) at which the pump operates. It is located
    at the intersection of the system curve and the
    performance curve of a pump. It corresponds to
    the flow and head required for the process.

60
Glossary in Pumps and Pumping System
  • Peripheral pump also known as regenerative or
    regenerative turbine pump. These are low capacity
    (150 gpm or 34 m3/h) high head (5400 ft or 1645
    m) pumps. The impeller has short vanes at the
    periphery and these vanes pass through an annular
    channel. The fluid enters between two impeller
    vanes and is set into a circular motion, this
    adds energy to the fluid particles which travel
    in a spiral like path from the inlet to the
    outlet. Each set of vanes continuously adds
    energy to the fluid particles.
  • Performance curve A plot of Total Head vs. flow
    for a specific pump model, impeller diameter and
    speed (syn characteristic curve, water
    performance curve)

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Glossary in Pumps and Pumping System
  • Pipe roughness A measurement of the average
    height of peaks producing roughness on the
    internal surface of pipes. Roughness is measured
    in many locations and then averaged, it is
    usually defined in micro-inches RMS (root mean
    square).
  • Piping pressure (maximum) it may be necessary in
    certain applications to check the maximum rating
    of your pipes to avoid bursting due to excessive
    pressure. The ASME pressure piping code B31.3
    provides the maximum stress for pipes of various
    materials.
  • Pitot pump also know as rotating casing pump.
    This pumps specialty is low to medium flow rates
    at high pressures. It is frequently used for high
    pressure shower supply on paper machines.

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Glossary in Pumps and Pumping System
  • Pressure The application of a force to a body
    producing more or less compression within the
    liquid. In a static fluid pressure varies with
    height.
  • Pressure head an expression of energy,
    specifically it is energy per unit weight of
    fluid displaced.
  • Progressive cavity pump a positive displacement
    pump. These pumps are ideal for fluids that are
    just too tough for other pumps to handle. e.g.
    pastes, greases, sludge etc. They consist of only
    one driven metal rotor rotating within an
    elastomer lined (elastic) stator.
  • Pseudoplastic The property of a fluid whose
    viscosity increases slowly with rate of shear.

63
Glossary in Pumps and Pumping System
  • Pumps as turbines (PAT) Pumps used in reverse to
    act as turbines.
  • Radial flow pump refers to the design of a
    centrifugal pump for medium head and medium flow
    or high head and low flow. The value of the
    specific speed number will provide an indication
    whether a radial pump design is suitable for your
    application.
  • Radial vane pump also known as partial emission
    pump or vane pump. A frame mounted, end suction,
    top centerline discharge, ANSI pump designed
    specifically to handle corrosive chemicals at low
    flows.
  • Recessed impeller pump sometimes known as vortex
    pump. This is a frame-mounted, back pull-out, end
    suction, recessed impeller, tangential discharge
    pump designed specifically to handle certain
    bulky or fibrous solids, air or gas entrained
    liquids or shear sensitive liquids.

64
Glossary in Pumps and Pumping System
  • Recirculation at low flow and high flow compared
    to the flow at the B.E.P. the fluid will start to
    recirculate or move in a reverse direction at the
    suction and at the discharge.
  • Reynolds number the Reynolds number is
    proportional to the ratio of velocity and
    viscosity, the higher the number (higher than
    4000 for turbulent flow) the more turbulent the
    flow and the less viscosity has an effect.
  • Screw impeller The screw centrifugal impeller is
    shaped like a tapered Archimedes screw.
    Originally developped for pumping live fish, the
    screw centrifugal pump has become popular for
    many solids handling applications.
  • Self-priming pump a pump that does not require
    priming or a initial filling with liquid. The
    pump casing carries a reserve of water that helps
    create a vacuum that will lift the fluid from a
    low source.

65
Glossary in Pumps and Pumping System
  • Shut-off head The Total Head corresponding to
    zero flow on the pump performance curve.
  • Side channel pump is a pump that provides high
    head at low flows with the added benefit of being
    able to handle gases.
  • Siphon A system of piping or tubing where the
    exit point is lower than the entry point and
    where some part of the piping is above the free
    surface of the fluid source.
  • Sludge pump certain types of sludges tend to
    settle very quickly and are hard to keep in
    suspension
  • Slurry pump a rugged heavy duty pump intended
    for aggressive or abrasive slurry solutions
    typically found in the mining industry with
    particles of various sizes. It achieves this by
    lining the inside of the pump casing as well as
    the impeller with rubber.

66
Glossary in Pumps and Pumping System
  • Specific gravity (SG) the ratio of the density
    of a fluid to that of water at standard
    conditions. If the SG is 1 then the density is
    the same as water, if it is less than 1 then the
    fluid is less dense than water and heavier than
    water if the SG is bigger than 1. Mercury has an
    SG of 14, gasoline has an SG of 0.8. The
    usefulness of specific gravity is that it has no
    units since it is a comparative measure of
    density or a ratio of densities therefore
    specific gravity will have the same value no
    matter what system of units we are using
  • Specific speed a number that provides an
    indication what type of pump (for example radial,
    mixed flow or axial) is suitable for the
    application.

67
Glossary in Pumps and Pumping System
  • Standard volute pump close coupled The volute is
    the casing which has a spiral shape. The motor
    shaft is connected to the impeller without an
    intermediate coupling providing a compact
    arrangement. The flow range is typically less
    than 300 gpm.
  • Standard volute pump separately coupled The
    volute is the casing which has a spiral shape.
    The motor shaft is connected to the impeller with
    an intermediate shaft with two couplings.
  • Stuffing box the joint that seals the fluid in
    the pump stopping it from coming out between the
    casing and the pump shaft.
  • Submersion Submersion as used here is the height
    between the free surface of a suction tank and
    the pump intake pipe.
  • Suction flow splitter a rib of metal across the
    pump suction that is installed on certain pumps.
    It's purpose is to remove large scale vortexes so
    that the stream lines are as parallel as possible
    as the fluid enters the impeller eye.

68
Glossary in Pumps and Pumping System
  • Suction guide a device that helps straighten the
    flow ahead of a pump that has a 90 degree elbow
    immediately ahead of it.
  • Suction specific speed a number that indicates
    whether the suction conditions are sufficient to
    prevent cavitation. According to the Hydraulic
    Institute the suction specific speed should be
    less than 8500. Other experiments have shown that
    the suction specific speed could be as high as
    11000.
  • Suction Static Head The difference in elevation
    between the liquid level of the fluid source and
    the centerline of the pump This head also
    includes any additional pressure head that may be
    present at the suction tank fluid surface, for
    example as in the case of a pressurized suction
    tank.

69
Glossary in Pumps and Pumping System
  • Suction Static Lift The same definition as the
    Suction Static head. This term is only used when
    the pump centerline is above the suction tank
    fluid surface.
  • System as in pump system. The system includes
    all the piping, including the equipment, starting
    at the inlet point (often the fluid surface of
    the suction tank) and ending at the outlet point
    (often the fluid surface of the discharge tank).
  • System Curve A graphical representation the pump
    Total Head vs. flow. Calculations are done for
    the total head at different flow rates, these
    points are linked and form a curve called the
    system curve. It can be used to predict how the
    pump will perform at different flow rates. The
    Total head includes the static head which is
    constant and the friction head and velocity head
    difference which depends on the flow rate. The
    intersection of the system curve with the pump
    characteristic curve defines the operating point
    of the pump.

70
Glossary in Pumps and Pumping System
  • System requirements Those elements that
    determine Total Head friction and the system
    inlet and outlet conditions (for example
    velocity, elevation and pressure).
  • Thixotropic The property of a fluid whose
    viscosity decreases with time.
  • Total Head The difference between the pressure
    head at the discharge and suction flange of the
    pump
  • Turbulent The behavior of fluid articles within
    a flow stream characterized by the rapid movement
    of particles in many directions as well as the
    general direction of the overall fluid flow.
  • Total Static Head The difference between the
    discharge and suction static head including the
    difference between the surface pressure of the
    discharge and suction tanks if the tanks are
    pressurized

71
Glossary in Pumps and Pumping System
  • Vane pass frequency when doing a vibration
    analysis this frequency (no. of vanes times the
    shaft speed) and it's even multiples shows up as
    a peak which can indicate a damaged or imbalanced
    impeller.
  • Vacuum pressure less than atmospheric pressure.
  • Vane pump (hydraulic) a positive displacement
    pump. Vane pumps are used successfully in a wide
    variety of applications (see below). Because of
    vane strength and the absence of metal-to-metal
    contact, vane pumps are ideally suited for
    low-viscosity, non lubricating liquids up to
    2,200 cSt / 10,000 SSU. Such liquids include LPG,
    ammonia, solvents, alcohol, fuel oils, gasoline,
    and refrigerants.
  • Vapor pressure The pressure at which a liquid
    boils for a specific temperature.

72
Glossary in Pumps and Pumping System
  • Venturi (Bernoulli's law) a venturi is a pipe
    that has a gradual restriction that opens up into
    a gradual enlargement. The area of the
    restriction will have a lower pressure than the
    enlarged area ahead of it.
  • Viscous drag pump a pump whose impeller has no
    vanes but relies on fluid contact with a flat
    rotating plate turning at high speed to move the
    liquid.
  • Water hammer (pressure surge) If in systems with
    long discharge lines,(e.g. in industrial and
    municipal water supply systems ,in refineries and
    power stations) the pumped fluid is accelerated
    or decelerated, pressure fluctuations occur owing
    to the changes in velocity. If these velocity
    changes occur rapidly , they propagate a pressure
    surge in the piping system, originating from the
    point of disturbance propagation takes place in
    both directions (direct waves),and these waves
    are reflected (indirect waves) at points of
    discontinuity ,e.g. changes of the cross
    sectional area ,pipe branches, control or
    isolating valves, pumps or reservoir. The
    boundary conditions decide whether these
    reflections cause negative or positive surges.
    The summation of all direct and indirect waves at
    a given point at a given time produces the
    conditions present at this point.
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