350mm Submersible Sewage Pumps for Large-City Sewage Stations

Four variants, and motor speed tells the real story of how this range is built. The 1500 m³/h / 15m / 90kW unit runs at 740 rpm, an 8-pole motor, the slowest in the whole catalogue at this point in the range, while the otherwise similar 1200 m³/h / 18m / 90kW variant runs at 980 rpm (6-pole). Same power, same bore, different pole count, because the low-head high-flow point favors a big, slow impeller and the higher-head point favors a smaller, faster one. Both higher-head models above them stay at 980 rpm and simply add power to reach further.

The 740 rpm unit is also the most efficient entry in the table at 87%. Slower speed generally means lower hydraulic losses at the impeller tip, which is part of why an 8-pole motor gets used whenever head allows it, rather than defaulting to 4- or 6-pole across the board. Anyone specifying the 36m-head unit should note that at 160kW, the casing dimensions above (700×1666×2590mm) reflect a genuinely heavier build than the 90kW models sitting above it in the table. The lifting gear and foundation spec don’t carry over automatically.