1. ROTODYNAMIC PUMPS

2. Rotodynamic Pumps Mixed flow Axial flow Centrifugal Rotodynamic Turbine PUMP Positive displacement Diaphragm Piston Plunger Reciprocating Rotary Gear Lobe Sliding Vane Screw

3. Axial and Mixed flow: Axial and Mixed Flow Pumps are the normal choice for high-volume, low-pressure pumping duties and particularly for large-scale primary water supplies, flood control, irrigation and drainage. Such types are available in a wide range of sizes and capacities. It is a general characteristic of such pumps that the power input curve is much flatter than that of a centrifugal pump , thus input power demand does not vary very much with the working point. Hydraulic performance, however, differs appreciably. Rotodynamic Pumps

4. Axial and Mixed flow: Axial flow pumps generate head pressure through an axial motion developed by a combination of propeller and internal vane design . The combination induces fluids to travel strictly along the axial of the pump drive shaft. The mixed flow pump employs a chamber /impeller /vane design to impart both an axial and radial motion to fluids traveling downstream. Rotodynamic Pumps This powerful motion is created by lifting the fluids with an impeller, while simultaneously forcing fluids out against the bowl like impeller chamber.

5. Axial and Mixed flow: The outward movement known as an upper diffuser section . By combining axial and centrifugal motion , the mixed flow pump generates greater head pressure to downstream fluids than is possible with a single motion axial pump. These differences are noted in the generated comparative H-Q curve. Rotodynamic Pumps

6. Axial and Mixed flow: Rotodynamic Pumps Q η ,HP, Hd Q η ,HP, Hd Q η ,HP, Hd Q η ,HP, Hd Q η ,HP, Hd Q η ,HP, Hd

7. Axial and Mixed flow: Rotodynamic Pumps In the case of a mixed flow pump, the H-Q curve tends to be steep, with the point of maximum efficiency displaced towards maximum capacity.

8. Axial and Mixed flow: Rotodynamic Pumps The H-Q curve of an axial flow pump has substantial falling characteristics although the actual head obtainable is much lower. Efficiency is higher over a greater (percentage) range of head than for a centrifugal pump.

9. Axial and Mixed flow: Rotodynamic Pumps General form: Axial and mixed flow pumps are commonly mounted vertically , directly over a sump. This is most often the case when the source of water is a river or reservoir. Fluids enter through a flared suction bell that has been reinforced by heavy vanes. Driver Head shaft Seal Pump shaft Impeller Discharge elbow Column assembly Bowls Suction bell

10. Axial and Mixed flow: Rotodynamic Pumps General form: The vanes, in addition to lending support to the suction bell, act to direct the liquid flow parallel to the drive shaft as it travels upstream. Once past the suction bell, fluids encounter either an axial propeller or a mixed flow impeller. Driver Head shaft Seal Pump shaft Impeller Discharge elbow Column assembly Bowls Suction bell

11. Axial and Mixed flow: Rotodynamic Pumps General form: While differing in design, both are always dynamically balanced, one-piece castings, mounted on a stainless steel pump shaft. Driver Head shaft Seal Pump shaft Impeller Discharge elbow Column assembly Bowls Suction bell

12. Axial and Mixed flow: Rotodynamic Pumps Driver : The drive shaft may be encased in a tube or open, with supports properly spaced for intermediate shaft bearings. Positive drive is provided by a heavy-duty drive key and thrust collar. A variety of drivers may be used, however, electric motors and right angle gears are most common. Driver Head shaft Seal Pump shaft Impeller Discharge elbow Column assembly Bowls Suction bell

13. Axial and Mixed flow: Rotodynamic Pumps Driver : These types of drivers can be grouped into two categories: 1. Hollow shaft drivers - the pump shaft extends through a tube in the center of the rotor and is connected to the driver by a clutch assembly at the top of the driver. Driver Head shaft Seal Pump shaft Impeller Discharge elbow Column assembly Bowls Suction bell

14. Axial and Mixed flow: Rotodynamic Pumps Driver : These types of drivers can be grouped into two categories: 2. Solid shaft drivers - the rotor shaft is solid and projects below the driver-mounting base. This type driver requires an adjustable coupling between the pump and driver. Driver Head shaft Seal Pump shaft Impeller Discharge elbow Column assembly Bowls Suction bell

15. Axial and Mixed flow: Rotodynamic Pumps Column assembly: The column assembly is of two basic types, either of which may be used on close coupled units: Driver Head shaft Seal Pump shaft Impeller Discharge elbow Column assembly Bowls Suction bell

16. Axial and Mixed flow: Rotodynamic Pumps Column assembly: The column assembly is of two basic types, either of which may be used on close coupled units: 1. Open line shaft construction utilizes the liquid being pumped to lubricate the line shaft bearings.

17. Axial and Mixed flow: Rotodynamic Pumps Column assembly: The column assembly is of two basic types, either of which may be used on close coupled units: 2. Enclosed line shaft construction has an enclosing pipe around the line shaft and utilizes oil, grease or injected liquid to lubricate the line shaft bearings.

18. Axial and Mixed flow: Rotodynamic Pumps Column assembly: The column assembly will consist of column pipe, which connects the bowl assembly to the discharge head and carries the pumped liquid to the discharge head, the shaft, which connects the bowl assembly to the discharge head, the head shaft, which connects the line shaft to the driver.

19. Axial and Mixed flow: Rotodynamic Pumps Column assembly: Column pipe may be either threaded or flanged and may contain bearings if required for the particular unit. Note: Some units will not require a column assembly, having the bowl assembly connected directly to the discharge head. Note:

20. Axial and Mixed flow: Rotodynamic Pumps Discharge head assembly: The column assembly is of two basic types, either of which may be used on close coupled units:

21. Axial and Mixed flow: Rotodynamic Pumps The discharge head supports the driver and bowl assembly as well as supplying a discharge connection (the underground discharge connection will be located on one of the column pipe sections below the motor stand). Discharge head assembly:

22. Axial and Mixed flow: Rotodynamic Pumps A shaft sealing arrangement is located in the discharge head to seal the shaft where it leaves the liquid chamber. The shaft seal will usually be either a packing box or mechanical seal assembly. Discharge head assembly:

23. Axial and Mixed flow: Rotodynamic Pumps Bowl assemblies: The bowl assembly consists of impellers rigidly mounted on the bowl shaft, which rotate and impart energy to the fluid. The bowls (or diffusers) contain the fluid at increased pressure and direct it vertically to the next stage and eventually to the column pipe.

24. Axial and Mixed flow: Rotodynamic Pumps Bowl assemblies: The suction bell or case directs the fluid into the first stage impeller. Bearings are located in the suction bell, discharge case, and between each impeller. Impeller

25. Axial and Mixed flow: Rotodynamic Pumps Bowl assemblies: The rotating element is mounted in an individual housing, which is usually replaceable and situated just above the section bell, close to the pump inlet. The housing may be bronze, stainless steel or any other material similar to the impeller. Why ? Impeller

26. Axial and Mixed flow: Rotodynamic Pumps Bowl assemblies: The same resistance to shock. The same thermal extension. Why ? To keep a clearance between impeller and casing as designed (performance of the pump). Impeller

27. Axial and Mixed flow: Rotodynamic Pumps Bowl assemblies: After emerging from the housing, fluids travel past an upper diffuser chamber and out through the guide case. The guide case, consisting of a column pipe and discharge elbow is of welded steel plate or cast iron.

28. Axial and Mixed flow: Rotodynamic Pumps Bowl assemblies: Sections are flanged or bolted together. A registered fit is used to maintain proper alignment on all mated parts.

29. Axial and Mixed flow: Rotodynamic Pumps Pullout options, which make for easier maintenance and inspection, are a common feature of these pumps, the best designs permit removal of the entire bowl assembly (including all rotating parts, diffuser, impeller housing and suction bell) through the outer shell, without disturbing either the discharge or floor plate connections. Pullout options:

30. Channel impeller pumps: Rotodynamic Pumps A channel impeller pump employs an impeller with turbine-type blades mounted on the periphery running in an annular channel (or channels) surrounding the periphery of the wheel. In practice, only two main subtypes emerge, known generally as the peripheral pump and side channel pump respectively.

31. Rotodynamic Pumps The main difference is in the form and positioning of the channels: Channel impeller pumps: The peripheral pump has a double-sided channel in which the liquid circulates, this channel being located partly in the cylindrical part of the casing and partly in the side plates. The side-channel pump has two channels cut in the side plates only, adjacent to each side of the impeller blades.

32. Rotodynamic Pumps Characteristics are quite different, eg the side-channel pump is self-priming and can develop a much higher head, although its efficiency is lower. Hence, the two are distinct types. Channel impeller pumps: The peripheral pump is also known as a regenerative pump .

33. Rotodynamic Pumps H-Q Efficiency BHP HEAD,BHP & Efficiency 100% Peripheral Capacity Channel impeller pumps:

34. Rotodynamic Pumps H-Q Efficiency BHP HEAD,BHP & Efficiency 100% Side-channel Capacity Channel impeller pumps:

35. Rotodynamic Pumps H-Q Efficiency BHP HEAD,BHP & Efficiency 100% Side-channel Capacity H-Q Efficiency BHP HEAD,BHP & Efficiency 100% Peripheral Capacity Channel impeller pumps:

36. Rotodynamic Pumps Centrifugal Regenerative Axial flow Axial flow Capacity HEAD Regenerative pumps have a substantially straight and sleep H-Q curve. Pressure developed tends to rise sharply with decreasing capacity making this type unsuitable for discharge regulation by throttling. Power output falls with increasing capacity. Channel impeller pumps:

37. Rotodynamic Pumps Mixed flow Axial flow Centrifugal Rotodynamic Turbine PUMP Positive displacement Diaphragm Piston Plunger Reciprocating Rotary Gear Lobe Sliding Vane Screw

38. Turbine pumps ( Regenerative ): Rotodynamic Pumps Turbine pumps obtain their name from the many vanes machined into the periphery of the rotating impeller. Heads over 900 feet are readily developed in a two-stage pump.

39. Turbine pumps ( Regenerative ): Rotodynamic Pumps The impeller, which has very tight axial clearance and uses pump channel rings, displays minimal recirculation losses. The channel rings provide a circular channel around the blades of the impeller from the inlet to the outlet.

40. Turbine pumps ( Regenerative ): Rotodynamic Pumps Liquid entering the channel from the inlet is picked up immediately by the vanes on both sides of the impeller and pumped through the channel by the shearing action. The process is repeated over and over with each pass imparting more energy until the liquid is discharged .