1. 1
Designing of submarine ballast-Designing of submarine ballast-
drainage centrifugal pump with lowdrainage centrifugal pump with low
noise & vibration levelnoise & vibration level
Ballast-Drainage System

2. 2
ContentContent
 Piping & Instrumentation DiagramPiping & Instrumentation Diagram 44
 Pump Unit PerformancePump Unit Performance 55
 Impeller ProfileImpeller Profile 66
 Impeller detail drawingImpeller detail drawing 77
 Diffuser ProfileDiffuser Profile 88
 General ArrangementGeneral Arrangement 99
 Cross Sectional DrawingCross Sectional Drawing 1111
 Dynamic Balancing of the Rotor AssemblyDynamic Balancing of the Rotor Assembly 1313
 Researching PartResearching Part 1414
 Balancing of Axial & Radial ForcesBalancing of Axial & Radial Forces 1717
 Vibration & Noise ProtectionVibration & Noise Protection 1818
 NPSHr ReductionNPSHr Reduction 1919

3. 3
Content (continuation)Content (continuation)
 Impeller Fabrication MethodImpeller Fabrication Method 2020
 Impeller MachiningImpeller Machining 2121
 Adapter for Impeller MachiningAdapter for Impeller Machining 2222
 Manufacturing CostsManufacturing Costs 2323
 ConclusionsConclusions 2424

4. 4
Piping & Instrumentation DiagramPiping & Instrumentation Diagram
4 – Gate valve
5 – Ballast system piping
6 – Sea inlet
7 – Sluice valve
8 – Filter (mud box)
9 – Stop valves (switchgear)
10 – Ballast pump
11 – Drainage pump
12 – Gate valve
13 – Separator
14 – Hand pump
15 – Protection cell
16 – Drainage piping
1 – Suction filter
2 – Mud box
3 – Nonreturn valve

5. 5
Pump Unit PerformancePump Unit Performance
 Head = 30m
 Capacity = 300m3/h
 NPSHa = 5m
 NPSHr = 0,7m
 Ns = 2935
 Nssimpeller = 13010
 Rated Power = 45,93kW
 E-motor Power = 55kW
 Speed = 1500rpm
 Efficiency = 55%

6. 6
Impeller ProfileImpeller Profile
Vanes profile
Velocity vector
diagram
(outlet)
Velocity vector
diagram
(inlet)

7. 7
Impeller detail drawingImpeller detail drawing
Balancing
holes
Space vanes
Back wear
ring design

8. 8
Diffuser ProfileDiffuser Profile
Back vanes
Inlet
Outlet

9. 9
General ArrangementGeneral Arrangement
Gap between pump casing and
mounting surface

10. 10
General ArrangementGeneral Arrangement
Elastomer between pump
casing supports and mounting
surface

11. 11
Cross Sectional DrawingCross Sectional Drawing
Sleeve bearings
Axial-vortex stage
Balance drum

12. 12
Cross Sectional DrawingCross Sectional Drawing
Provisions for vibration
measurement
Junction box
Cable glands

13. 13
Dynamic Balancing of the Rotor AssemblyDynamic Balancing of the Rotor Assembly

14. 14
Researching PartResearching Part
Inducer Axial-Vortex Stage
NPSHr & Noise level

15. 15
Researching PartResearching Part
 Inducer
• Amount of back flow is bigger
• Noise level is higher
• NPSHr is higher
 Axial-Vortex Stage
• Amount of back flow is less
• Noise level is lower
• NPSHr is lower

16. 16
Researching PartResearching Part
NPSHr & Noise level
1 – Impeller
2 – Inducer
3 – Axial-Vortex Stage
First acoustical positive
suction head
Second acoustical positive
suction head
Net positive suction head
(Head drop by 3%)
Net positive suction head
(Head drop by 25%)

17. 17
Balancing of Axial & Radial ForcesBalancing of Axial & Radial Forces
 Axial loadAxial load
• Back impeller wear ringBack impeller wear ring
• Impeller balancing holesImpeller balancing holes
• Balancing drumBalancing drum
• Rotor weight reductionRotor weight reduction
 Radial loadRadial load
• Diffuser designDiffuser design

18. 18
Vibration & Noise ProtectionVibration & Noise Protection
 Static balancing of rotate partsStatic balancing of rotate parts
 Dynamic balancing of the rotor assemblyDynamic balancing of the rotor assembly
 Sleeve bearingsSleeve bearings
 Low number of revolutionsLow number of revolutions
 Low NPSHrLow NPSHr
 Gap between pump casing and mountingGap between pump casing and mounting
basebase
 Elastomer between casing supports andElastomer between casing supports and
mounting basemounting base
 Flexible suction & discharge transitionFlexible suction & discharge transition
piecespieces

19. 19
NPSHr ReductionNPSHr Reduction
 Using of Axial-Vortex StageUsing of Axial-Vortex Stage
 Reducing number of revolutionsReducing number of revolutions
 Increasing impeller eye squareIncreasing impeller eye square

20. 20
Impeller Fabrication MethodImpeller Fabrication Method
Casting Rotary machining (CNC unit) Turning
Turn broaching Turning Radial drilling

21. 21
Impeller MachiningImpeller Machining
Radial drilling
Rotary machining (CNC unit) Turn broaching

22. 22
Adapter for Impeller MachiningAdapter for Impeller Machining

23. 23
Manufacturing CostsManufacturing Costs
C1 – Material cost
C2 – Buy-out cost
C3 – Factory overheads
C4 – Salary for involved employees
C1 = 43,7% C2 = 21,3%
C3 = 11,6%
C4 = 8,7%
C5 = 5,8%
C6 = 3,6%
C7 = 2,3%
C8 = 3%
C5 – Equipment maintenance cost
C6 – Shop overheads
C7 – Social insurance for involved employees
C8 – Out-of-process costs

24. 24
ConclusionsConclusions
 Noise & Vibration Level ControlNoise & Vibration Level Control
 Weight & Overall Dimensions ControlWeight & Overall Dimensions Control
 High ReliabilityHigh Reliability
 Manufacturing Cost ReductionManufacturing Cost Reduction
 Easy Maintenance & RepairEasy Maintenance & Repair
 InterchangeabilityInterchangeability
 Environment ProtectionEnvironment Protection