The Tsurumi PN series is a submersible semi-vortex pump for general drainage and wastewater duties — filter backwash, purge water, floor drainage and rainwater on fish farms, hatcheries and aquarium facilities, as well as septic, treatment-plant and construction drainage. Built from special resin and stainless steel, it’s lightweight and doesn’t rust, and the semi-vortex impeller design gives efficient performance with moderate solids handling (10–20 mm).
Key Features
- Semi-vortex design — a vortex impeller in a low-height volute casing for efficient performance with moderate solids passage (10–20 mm)
- More head per kilowatt than a full vortex pump — the efficient choice on cleaner drainage
- Special resin and stainless steel construction — lightweight, corrosion-resistant, and tolerates seawater and rainwater duty
- Dual silicon carbide mechanical seals, oil lifter and anti-wicking cable entry for continuous submersed service
- Single-phase 240 V models (0.25 / 0.4 / 0.75 kW) are RCM certified; three-phase models to 3.7 kW
- Automatic float-switch (PNA), auto-alternation and guide-rail fitting versions available for unattended and duty/standby operation
- Back pull-out design for easy inspection and maintenance
Applications
- Fish farms, hatcheries and RAS facilities — filter backwash, purge water and floor drainage
- Ponds, waterscapes and aquariums
- Wastewater treatment plants, septic tanks and disinfection chambers
- Seawater and rainwater pumping
- Construction wastewater drainage and general water transfer
Technical Details
| Discharge Bore (mm) | Manual Model | Automatic Model | Motor Output (kW) | Phase | Starting Method | Solids Passage (mm) | Max Flow (L/min) | Max Head (m) |
|---|---|---|---|---|---|---|---|---|
| 40 | 40PN2.25S | 40PNA2.25S | 0.25 | Single | Capacitor Run | 10 | 245 | 9.0 |
| 40 | 40PN2.25 | 40PNA2.25 | 0.25 | Three | D.O.L. | 10 | 245 | 9.0 |
| 50 | 50PN2.4S | 50PNA2.4S | 0.4 | Single | Capacitor Run | 10 | 295 | 12.0 |
| 50 | 50PN2.4 | 50PNA2.4 | 0.4 | Three | D.O.L. | 10 | 295 | 12.0 |
| 50 | 50PN2.75S | 50PNA2.75S | 0.75 | Single | Capacitor Run | 10 | 355 | 15.0 |
| 50 | 50PN2.75 | 50PNA2.75 | 0.75 | Three | D.O.L. | 10 | 355 | 15.0 |
| 50 | 50PN21.5 | 50PNA21.5 | 1.5 | Three | D.O.L. | 20 | 665 | 17.2 |
| 80 | 80PN22.2 | 80PNA22.2 | 2.2 | Three | D.O.L. | 20 | 715 | 19.7 |
| 80 | 80PN23.7 | 80PNA23.7 | 3.7 | Three | D.O.L. | 20 | 900 | 26.1 |
Max flow and max head are taken from Tsurumi’s 50 Hz performance curves — use the curve below to check your exact duty point.
Performance Curve
Downloads
Frequently Asked Questions
What’s the difference between the manual and automatic models?
Automatic (PNA) models carry an integrated float switch, so the pump starts and stops with the water level and won’t run dry — ideal for unattended sumps and pits. Auto-alternation versions share the load between two pumps in duty/standby installations, and guide-rail fitting versions make pit servicing easier. The video below shows how the automatic models work.
Can it handle salt water?
The resin and stainless construction tolerates seawater and rainwater pumping duty. For anything permanently immersed in salt water — intakes, live-holding, marine RAS — the titanium TM series is the right tool.
Should I choose the PN or the PU series?
Pick the PN on cleaner drainage — its semi-vortex design gives more head per kilowatt. If the water carries larger or stringy solids, the vortex PU series passes solids to 46 mm without clogging.
Which model do I need?
It comes down to your duty point — flow, delivery head, pipe run and what’s in the water. Send us those details and we’ll confirm the right model, price and lead time.
