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SKU: 93209309
Grundfos NB 50-200/181 Cast Iron 11 kW End Suction Centrifugal Pump with Closed Impeller
Australia-Wide
(08) 9240 2992
Official Grundfos
Peace of Mind
Product Overview
The NB 50-200/181 single-stage end-suction pump operates on a 415 V three-phase supply rated at 11 kW drive power. Built with an axial inlet port (DN 65) and top radial outlet port (DN 50), the unit connects into commercial hydronic heating networks, cooling tower water loops, and facility fluid transfer lines.
Under full duty load, the pump generates 1184 L/Min rated flow capacity and reaches a maximum head threshold of 38.94 m. The heavy volute housing uses electrocoated cast iron to resist internal corrosion. A stainless steel impeller rotor assembly with bronze wear rings drives fluid transfer. Net product weight equals 147 kg.
Drive power on the NB 50-200/181 pump comes from a 11 kW electric motor operating on a 415 V three-phase electrical connection. Full-load running current measures 21.5 Amps. The pump processes liquid media over temperatures from -25°C to 120°C under line pressures up to 16 bar. Pipe connections use DN 65 suction and DN 50 discharge flanges.
Built with an IP55 rated motor enclosure and Class F insulation, the NB 50-200/181 electric motor incorporates internal PTC thermistor sensors against overheating. Servicing is simplified by the back-pull-out structural layout, enabling complete rotor and drive removal without disconnecting suction or discharge pipe joints.
Features
- EN733 and ISO2858 dimensional compliance ensures interchangeability with other standard end-suction pumps across commercial and industrial installations.
- ATEX Zone 1, 2, 21 or 22 certification available for operation in potentially explosive atmospheres (except E-model variants).
- Integrally cast suction and discharge ports with dedicated vent and drain ports provide direct connection points without additional fittings.
- No baseplate or grouting required to maintain correct shaft alignment and vibration levels within Hydraulic Institute standards.
- Cataphoretic electrocoating on cast iron internal surfaces provides barrier protection against oxidative corrosion in hydronic circulation loops.
- Close-coupled configuration eliminates coupling alignment procedures and reduces overall installation footprint compared to long-coupled alternatives.
- Ball bearing support arrangement accommodates both radial and axial thrust loads generated during continuous duty operation at rated speed.
IMPORTANT: Bulk freight charges apply. Please contact us for a freight quote before ordering.
SPECIFICATIONS
| Max Flow | 1184 L/Min |
| Max Head | 38.94 m |
| Power | 11 kW / 415v |
| Rated Current | 21.5 Amps |
| Suitable For | High-Capacity Plant Room Pumping |
| Body Material | Cast Iron |
| Liquid Temperature | '-25°C to 120°C |
| Inlet Size | 65 mm |
| Outlet Size | 50 mm |
| Warranty | 24 Months |
Warranty & Returns
All products supplied by Foundation Pumps are covered by a minimum 12-month warranty unless otherwise stated. Some brands may offer longer manufacturer warranties. Warranty covers manufacturing defects, faulty materials and workmanship under normal use.
- Products must be installed correctly and in accordance with the manufacturer’s instructions.
- Warranty does not cover incorrect installation, misuse, dry running, normal wear and tear, unauthorised repairs or damage caused by external factors.
- Proof of purchase, photos, videos and installation details may be requested when assessing a warranty claim.
- The customer is responsible for returning the product to Foundation Pumps or the nominated service centre unless otherwise agreed.
- Removal, reinstallation, labour and associated site costs are generally the customer’s responsibility unless required under Australian Consumer Law.
- Change-of-mind returns may be accepted within 30 days provided the product is unused, uninstalled and returned in its original packaging.
- Customers are responsible for return freight costs for change-of-mind returns.
- Restocking fees may apply to special-order, bulky or non-stocked products.
- Used, installed or specially ordered products may not be eligible for change-of-mind returns.
- If a product arrives damaged or faulty, please contact Foundation Pumps as soon as possible so we can assist with the appropriate repair, replacement or refund.
Your rights under Australian Consumer Law are not affected.
How much fluid can this pump evacuate during peak demand?
Peak fluid displacement on the Grundfos NB 50-200/181 delivers up to 1184 L/Min under rated operating conditions.
How is the pump casing constructed to resist mechanical and fluid wear?
High-grade EN-GJL-250 components in the NB 50-200/181 protect internal passages against corrosive fluid contact.
How much electricity and current does this pump draw under load?
It operates on 415 V three-phase power, with the NB-50-200-181 utilizing a durable 11 kW motor rated at 21.5 Amps.
How deep can this pump be installed underwater in a wet well?
Thermal ratings for the NB 50 200 181 accommodate working liquid temperatures -25°C to 120°C under standard operating pressure.
What total dynamic head can this pump overcome in vertical pipework?
Pumping performance for the NB/50/200/181 provides up to 38.94 m of vertical dynamic lift, depending on system friction and line sizing.
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