End Suction
| Identification | |
| Manufacturer | Grundfos |
| Series | NB |
| Model / size | NB 65-250 |
| Pump type | End Suction |
| Spec code | PS-ES-026 |
| Duty & power | |
| Min flow | 25 m³/hr |
| Max flow | 130 m³/hr |
| Min head | 15 m |
| Max head | 85 m |
| Max power | 45 kW |
| NPSHr | 4.9 m |
| Efficiency at BEP | 65 % |
| Drive & electrical | |
| Starting method | Soft Starter or VFD (mandatory for >15kW to limit starting current) |
| VFD compatible | Yes (10-60 Hz) |
| Motor IE class | IE3 (mandatory EU/MEPS) / IE4 optional |
| Insulation class | Class F (155°C) standard |
| IP rating | IP55 |
| Materials & sealing | |
| Casing | Cast Iron |
| Impeller | Bronze |
| Shaft | SS 420 |
| Seal type | Mechanical Seal |
| API seal plan | Plan 11 (internal recirculation) — standard single seal |
| Application | |
| Service | Potable Water, Cooling |
| Key features | Large flow end suction, VFD ready |
A complete, shareable page for a single pump. It plots the performance curve (head, efficiency and NPSHr against flow, with the best-efficiency point marked, or dosing flow against stroke), decodes the API 682 / ISO 21049 mechanical seal plan, and lists the full specification — duty and operating range, drive and motor, materials of construction, build and reliability, connections, weight and certifications. Pop-up panels give the type-specific preventive-maintenance schedule (daily to annual tasks with procedures) and a troubleshooting guide (symptoms, probable causes and recommended solutions).
Run a centrifugal pump near its BEP and keep dosing pumps in their recommended stroke band. Data is from the engineering reference database — confirm against the manufacturer's certified curve before procurement.
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