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, diuser 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 Dierential pressure across the pump ....................35
2.5.1 Total pressure dierence .................................35
2.5.2 Static pressure dierence .................................35
2.5.3 Dynamic pressure dierence ..........................35
2.5.4 Geodetic pressure dierence ........................ 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 Eciency ....................................................................................... 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 eciency 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
8