Brochure
Contents
Chapter 1. Introduction to Centrifugal Pumps ...............11
1.1 Principle of centrifugal pumps .......................................12
1.2 The pump’s hydraulic components ............................13
1.2.1 Inlet flange and inlet ............................................14
1.2.2 Impeller ..........................................................................15
1.2.3 Coupling and drive .................................................17
1.2.4 Impeller seal ...............................................................18
1.2.5 Cavities and axial bearing ............................... 19
1.2.6 Volute casing, diuser and
outlet flange ...............................................................21
1.2.7 Return channel and outer sleeve .................23
1.3 Pump types and systems ................................................... 24
1.3.1 The UP pump .............................................................25
1.3.2 The TP pump ..............................................................25
1.3.3 The NB pump .............................................................25
1.3.4 The MQ pump ...........................................................25
1.3.5 The SP pump .............................................................26
1.3.6 The CR pump ............................................................. 26
1.3.7 The MTA pump ........................................................ 26
1.3.8 The SE pump...............................................................27
1.3.9 The SEG pump ...........................................................27
1.4 Summary .............................................................................................27
Chapter 2. Performance curves ............................................29
2.1 Standard curves ...................................................................... 30
2.2 Pressure ..........................................................................................32
2.3 Absolute and relative pressure ......................................33
2.4 Head ............................................................................................ 34
2.5 Dierential pressure across the pump ....................35
2.5.1 Total pressure dierence .................................35
2.5.2 Static pressure dierence .................................35
2.5.3 Dynamic pressure dierence ..........................35
2.5.4 Geodetic pressure dierence ........................ 36
2.6 Energy equation for an ideal flow ................................37
2.7 Power .............................................................................................. 38
2.7.1 Speed .............................................................................. 38
2.8 Hydraulic power ...................................................................... 38
2.9 Eciency ....................................................................................... 39
2.10 NPSH, Net Positive Suction Head ................................40
2.11 Axial thrust.................................................................................. 44
2.12 Radial thrust ............................................................................... 44
2.13 Summary .......................................................................................45
Chapter 3. Pumps operating in systems ...........................47
3.1 Single pump in a system....................................................49
3.2 Pumps operated in parallel .............................................. 50
3.3 Pumps operated in series ...................................................51
3.4 Regulation of pumps .............................................................51
3.4.1 Throttle regulation ................................................52
3.4.2 Regulation with bypass valve ........................52
3.4.3 Start/stop regulation ...........................................53
3.4.4 Regulation of speed ..............................................53
3.5 Annual energy consumption ......................................... 56
3.6 Energy eciency index (EEI).............................................57
3.7 Summary ...................................................................................... 58
Chapter 4. Pump theory .........................................................59
4.1 Velocity triangles ....................................................................60
4.1.1 Inlet ................................................................................. 62
4.1.2 Outlet ............................................................................. 63
4.2 Euler’s pump equation ........................................................64
4.3 Blade shape and pump curve .........................................66
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