Design Of Wilo Pumps
Single-stage low-pressure centrifugal Wilo Pumps with axial suction point, according to EN 733 and ISO 5199, mounted on a baseplate.
Application Wilo Pumps
- For pumping heating water (in accordance with VDI 2035), water-glycol mixtures and cooling and cold water without abrasive substances in heating, cold water and cooling water systems
- For applications regarding the municipal water supply, irrigation, building services, industry, power stations etc. (e.g. circulation, transfer and pressure-boosting tasks)
Type key of Wilo Pumps
| Example | NL 40/200B-11/2 |
| NL | Standard pump with axial suction |
| 40 | DN for the pressure flange |
| 200B | Nominal diameter of impeller |
| 11 | Rated motor power P2 [kW] |
| 2 | number of poles |
Special features/product advantages of Wilo Pumps
- Reduced life-cycle costs through optimised efficiency levels
- Bidirectional, force-flushed mechanical seal
- Low NPSH values, best cavitation properties
- Shaft coupling with or without intermediate sleeve
- Shaft deflection satisfies the requirements of ISO 5199
Technical data of Wilo Pumps
- Minimum Efficiency Index (MEI) ≥ 0.4
- Permissible temperature range of -20°C to +120°C
- Mains connection 3~400 V, 50 Hz
- Protection class IP 55
- Nominal diameter DN 32 to DN 150
- Max. operating pressure 16 bar
Scope of delivery
- Wilo Pumps with free shaft end or
- Wilo Pumps on baseplate with coupling and coupling protection or
- Completely mounted pump on baseplate with electric motor
- Installation and operating instructions
Materials of Wilo Pumps
- Wilo Pumps housing and pressure lid: EN-GJL-250
- Bearing bracket: EN-GJL-250
- impeller: EN-GJL-250
(special version: G-CuSn10) - Shaft: X20Cr13
- Mechanical seal: AQ1EGG
(other mechanical seals on request)
Description/design of Wilo Pumps
- Wilo Pumps Single-stage low-pressure centrifugal pump as baseplate pump with axial suction piece with flanged bearing bracket and axis mounting for flexibly coupled drives.
- Spacer coupling (sleeve coupling) available as an option; they make it possible to leave the motor in position when removing the rotor unit
- Shaft deflection meets the requirements of ISO 5199
Commissioning
- If pumps with 2900 rpm are installed inside residential buildings, then corresponding noise reducing measures are to be implemented.
- Pump curves and specific motor powers depend on the respective fluid being pumped. Pump curves and power vary considerably when fluids are conveyed that differ from water in thickness and/or viscosity. For this, please observe the table “Recommended limit values for dimensioning”.
The recommended limit values for dimensioning are calculated as follows:
Qoptimum (volume flow at which the pump reaches its best efficiency), to be read from the individual pump curve; factors Qmin and Qmax , to be taken from the table “Recommended limit values for dimensioning”.Qmin dimensioning = Qmin x Qoptimum
Qmax dimensioning = Qmax x Qoptimum
Example: Size NL 32-125
Qmin = 0.3 x 8 = 2.4 m3/h
Qmax = 1.2 x 8 = 9.6 m3/h - Load-sensitive pump output
All Wilo standard pumps are equipped with IEC standard motors. The Wilo control devices are suitable for automatic load-sensitive speed control of pumps that are driven by any standard motors of conventional manufacture. - Main/standby mode
Accessories Wilo Pumps
Automatic speed control:
for automatic, infinitely variable pump power control. for additional information, see “Switchgears and control devices” section.
Note
Motors with efficiency class IE3, other voltages and frequencies on request
General notes – ErP (ecological design-) directive
- The benchmark for most efficient water pumps is MEI ≥ 0.70
- The efficiency of a pump with a trimmed impeller is usually lower than that of a pump with the full impeller diameter. The trimming of the impeller will adapt the pump to a fixed duty point, leading to reduced energy consumption. The minimum efficiency index (MEI) is based on the full impeller diameter.
- The operation of this water pump with variable duty points may be more efficient and economic when controlled, for example, by the use of a variable speed drive that matches the pump duty to the system.
- Information on benchmark efficiency is available at www.europump.org/efficiencycharts