Design Pumps
Multistage 8” submersible pumps in sectional construction for vertical and horizontal installation
Application Pumps
- For drinking water supply pumps / general water supply from boreholes and rainwater storage tanks
- Process water supply
- Municipal water supply
- Sprinkling and irrigation
- Pressure boosting pumps
- Pumping water in industrial applications pumps and pumps water control
- Utilisation of geothermal energy
- Utilisation in offshore areas
Type key Pumps
| Example: | Wilo-EMU NK 80.2-17 + NU 801-2/40 |
| Hydraulics: | NK 80.2-17 |
| NK | Hydraulics |
| 8 | Diameter of the hydraulic unit in inches [“] |
| 0 | Size |
| 2 | Impeller made of special material |
| 17 | Number of hydraulic stages |
| Motor: | NU 801-2/40 |
| NU | Submersible motor |
| 801 | Overall size (4… = 4″; 5…, 6… = 6″; 7…, 8… = 8″) |
| 2 | Number of poles |
| 40 | Package length |
Special features/product advantages Pumps
- Heavy-duty version made of cast iron or zinc-free bronze
- Pressure shroud in corrosion-free and hygienic stainless steel version with rubber bearings for reducing noise and vibration
- Impellers made of zinc-free bronze
- Drinking water version with ACS approval
- Optional Ceram CT coating for increasing efficiency
Technical data Pumps
- Mains connection: 3~400 V, 50 Hz
- Immersed operating mode: S1
- Max. fluid temperature (higher temperatures on request):
- NU 4… / NU 5… / NU 6… / NU 7… / NU 811 = 30 °C
- NU 801 = 20 °C
- Minimum pumps motor flow:
- NU 4… / NU 801 = 0.1 m/s
- NU 5… / NU 7… = 0.16 m/s
- NU 611 = 0.1 – 0.5 m/s
- NU 811 = 0.5 m/s
- Max. sand content: 35 g/m3
- Max. number of starts: 10‐20/h (depending on type)
- Max. immersion depth:
- NU 4…, NU 5… NU 7… = 350 m
- NU 611, NU 811 = 100 m
- NU 801 = 300 m
- Protection class: IP 68
- Control range for frequency converter:
- NU 4… / NU 5… / NU 7… / NU 611 / NU 811 = 30-50 Hz
- NU 801 = 25-50 Hz
Equipment/function Pumps
- Multistage submersible pumps -motor pumps with radial or semi-axial impellers
- Hydraulics and motor freely configurable according to power requirements
- Integrated non-return valve (depending on type)
- NEMA coupling
- Three-phase motor for direct or star-delta starting
- Hermetically cast motors
- Rewindable motors
Description/design Pumps
Submersible-motor pumps for vertical or horizontal installation.
Hydraulics pumps
Multistage submersible-motor pumps with radial or semi-axial hydraulics. Housing parts made of EN‐GJL or EN‐GJS with 2K coating or G‑CuSn10, impellers made of Noryl (NK 80…, 81…, 82…) or G‑CuSn10. Pressure port as threaded connection (types NK 80…, 81…, 82…) or flange connection (types KD…), integrated non-return valve. Pressure port as flange or threaded connection, without non-return valve (types K…, NK 86…, 87…).
Motor
Three-phase motor for direct and star-delta starting Sealed, hermetically cast motor with enamel-insulated winding, resin-impregnated (NU 4…, NU 5…, NU 7…) or rewindable motor with PVC‐insulated winding (NU 611…, NU 8…). Motor shroud made of stainless steel, A2/A4 quality.
Pumps connection as standard NEMA connection. Sealing of motor shaft achieved through the use of a rotary shaft seal (NU 4…) or mechanical seal made of solid silicon carbide material. Self-lubricating motor bearing. Thrust bearing with rockers for absorption of high axial thrust. Negative axial thrust is absorbed by the counter-thrust bearing.
Motors in the NU 4…, NU 5… and NU 7… series are filled with a water‐glycol mixture, motors in the NU 611 and NU 811 series are filled with a water-glycerine mixture. NU 611 and NU 8…series motors can also be filled with drinking water (T version). Frequency converter operation is permitted (SF 1.1).
Cooling
The motor is cooled by the fluid. The motor must always be operated in submerged state. The limit values for the max. fluid temperature and the minimum flow rate must not be exceeded. Vertical installation is possible optionally with or without cooling jacket. For horizontal installation, bearing brackets must be used for reinforcement of the unit. An anti-vortex plate or cooling jacket may be used to improve the inlet flow.
Pressure shroud
The pressure shroud is used for direct installation of the unit in the pipe system. Standard models are without mounted non-return valves. The maximum inlet pressure is 10 bar.
Configuration Pumps
- No suction mode is possible with these units!
- The unit must be fully immersed in water during operation.
Scope of delivery Pumps
- Hydraulics + motor fully assembled
- Connecting cable approved for drinking water, cable cross-section and length per standard design or per customer request
- Installation and operating instructions
Options Pumps
- Special materials pumps
- Drinking water version with ACS approval
- 60 Hz version
- PT100 sensor for thermal motor monitoring