The TSURUMI KRS822 is a heavy-duty submersible dewatering pump from Tsurumi's KRS series (officially classed as a general construction pump). It has a 200 mm (8-inch) discharge and a 22 kW 4-pole three-phase motor. It is the highest-head model in the standard KRS range, with a maximum head of 34.8 m, so it suits deep excavations, tunnels and other jobs where water has to be lifted higher or pushed through a long hose run. With a semi-open ductile-iron impeller, a grey cast-iron body and a low-speed motor, it handles site water carrying a small amount of sand and silt (up to 15% dry matter, pH 5–9, solids up to 25 mm).
Selection note: the KRS822 and the KRS822L share the same 200 mm discharge, 22 kW motor and frame, but their hydraulics differ. The KRS822 is the high-head version (34.8 m max. head, 5,300 L/min max. capacity); the KRS822L trades head for flow (26 m, 5,900 L/min). Choose the KRS822 when your total head is high, and the KRS822L when head is moderate and you need more volume. The KRS822 is also a dewatering pump, not a slurry pump. It has no agitator and no high-chrome wear parts, so it is not suitable for settled sludge, dense sand slurry, desilting or dredging. For that duty, choose the KRD611 or KRS-200 slurry pumps, which have a high-chrome impeller and an agitator.
Key features
- Highest head in the standard KRS range: 34.8 m max. head, compared with 17.5 m for the KRS811, 21.5 m for the KRS815 and 26 m for the KRS822L, all with 200 mm discharges.
- Top-discharge, side-flow design: the motor stays cooled even when partly exposed, and the compact pump diameter fits confined spaces. Keep at least 345 mm of water for continuous running and do not run it dry for long periods.
- Double inside mechanical seals: silicon carbide (SiC) faces on both the upper and lower seals, running in an isolated oil chamber, with Tsurumi's original Oil Lifter to keep the seal faces lubricated and cooled even when the oil level drops to about one third of normal.
- Two dust seals: nitrile rubber lip seals keep abrasive particles away from the mechanical seals.
- Built-in circle thermal protector (CTP): cuts the motor circuit directly on overheating or overcurrent.
- Anti-wicking cable entry: stops water creeping along the cable cores into the motor if the sheath is damaged or the cable end is submerged.
- Low-speed 4-pole motor: continuous-duty dry-type induction motor at about 1,440–1,470 rpm at 50 Hz, paired with a cast-iron body for long service life.
- Starting: direct-on-line (DOL) as standard, star-delta available on request, and suitable for soft starters and variable-frequency drives (VFD).
Applications
- Construction sites: deep excavation and basement dewatering, temporary site drainage
- Tunnels: seepage water removal
- Bridge and dam works: drainage during construction
- Temporary drainage: provisional sewage drainage during works
- Storms and flooding: emergency drainage and boosting flood pumping stations
- Docks and reservoirs: shipyard dock drainage and reservoir drainage
Performance
The 34.8 m maximum head is the head at near-zero flow, and the 5,300 L/min (about 318 m³/h) maximum capacity is the end point of the performance curve. The two do not occur together: actual flow falls as total head (static head plus hose friction loss) rises. On the official 50 Hz curve, the section near zero flow is drawn dashed and is not recommended for continuous operation. Select the pump from the performance curve using your site's total head. If your head is modest and you need more volume, consider the KRS822L (5,900 L/min) or KRS1022 (12,000 L/min).
Technical specifications
TSURUMI KRS822 technical specifications (50 Hz)
| Item | Specification |
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| General |
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| Model | KRS822 |
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| Series | KRS (general construction pump, heavy-duty submersible dewatering) |
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| Discharge bore | 200 mm (8 in) |
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| Discharge connection | Hose coupling (standard) |
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| Hydraulic performance |
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| Max. head (at zero flow) | 34.8 m |
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| Max. capacity (curve end point) | 5,300 L/min (318 m³/h / 5.3 m³/min) |
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| Max. solids size | 25 mm |
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| Electrical |
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| Motor output | 22 kW |
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| Motor | 4-pole dry-type induction motor, continuous duty, IP68, insulation class F |
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| Speed | approx. 1,440–1,470 rpm (50 Hz) |
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| Power supply | 3-phase 50 Hz (voltage as per nameplate) |
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| Starting method | Direct-on-line (DOL); star-delta available on request; suitable for soft starters and VFDs |
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| Motor protection | Built-in circle thermal protector (CTP) |
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| Cable | 10 m (standard), chloroprene rubber sheath, anti-wicking cable entry |
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| Seals and bearings |
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| Shaft seal | Double inside mechanical seals, SiC faces upper and lower, oil-lubricated, with Oil Lifter |
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| Oil seals | 2 × nitrile rubber lip seals (dust seals) |
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| Lubricant | Turbine oil ISO VG32, 6,500 ml |
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| Bearings | Double-shielded deep-groove ball bearings (permanently lubricated) |
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| Materials |
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| Impeller | Semi-open, ductile cast iron (EN-GJS-700-2) |
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| Pump casing, suction cover | Grey cast iron (EN-GJL-200) |
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| Motor frame | Grey cast iron (EN-GJL-200) |
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| Shaft | 420 stainless steel (X30Cr13) |
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| Liquid limits |
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| Liquid | Stormwater, groundwater, wash water and sand-carrying site water |
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| Liquid temperature | 0–40 °C |
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| pH | 5–9 |
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| Max. dry matter | 15% |
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| Max. submersion depth | 40 m |
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| Dimensions and weight |
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| Dry weight (excl. cable) | 395 kg |
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| Dimensions (L × W × H) | 576 × 530 × 1241 mm |
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| Min. water level for continuous running | 345 mm |
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| Factory options |
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| Seawater-resistant version | Galvanic anodes plus seawater-resistant special cast-iron impeller (specify when ordering) |
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| High-temperature version | Liquid temperature up to 60 °C (special build) |
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Sources: Tsurumi KRS/KRD series catalogue (IB111), Tsurumi KRS model specification sheets and Tsurumi Europe KRS series data (50 Hz). Voltage, cable size and rated current of the Hong Kong supply version are as per the nameplate and confirmation from the Hong Kong agent.
KRS series comparison: 200 mm and larger
Tsurumi KRS series model comparison (50 Hz)
| Model | Discharge | Power | Max. head | Max. capacity | Max. solids |
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| KRS811 | 200 mm | 11 kW | 17.5 m | 5,500 L/min | 30 mm |
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| KRS815 | 200 mm | 15 kW | 21.5 m | 6,400 L/min | 25 mm |
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| KRS822L | 200 mm | 22 kW | 26 m | 5,900 L/min | 25 mm |
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| KRS822 (this product) | 200 mm | 22 kW | 34.8 m | 5,300 L/min | 25 mm |
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| KRS1022 | 250 mm | 22 kW | 12.2 m | 12,000 L/min | 25 mm |
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What's in the box
- KRS822 pump with attached 10 m cable × 1
- Hose coupling × 1
Optional accessories
- Male threaded coupling, in place of the standard hose coupling.
- Float switch (ask us for the supplied specification). On a three-phase pump the float must switch a contactor in a control panel, never the motor directly.
- Control panel or motor overload protector, set to the nameplate rated current.
Safety and installation
- The pump weighs about 395 kg dry. Lift it by its handle with a chain or shackle rated for the load. Never lift it by the cable or the hose.
- Electrical connection must be made by a registered electrical worker in line with local regulations, with earth-leakage protection. Set the overload relay to the nameplate rated current.
- A 22 kW direct-on-line start draws a high starting current. Size the cable, breaker and generator or transformer for a DOL start.
- Check rotation before first use: at start-up the pump body should kick anticlockwise when viewed from above. If it turns the wrong way, have an electrician swap two phases. Do not hold the handle while checking.
- After the built-in motor protector trips, the motor restarts automatically once it cools. Always isolate and lock off the power before inspection or servicing.
- Stand the pump on a firm or raised base so it does not sink into silt.
- Do not run continuously below a 345 mm water level, avoid prolonged dry running, and do not run continuously on the dashed near-zero-flow section of the performance curve.
- The standard model is not seawater-resistant and is not recommended for seawater or brackish water unless the factory seawater kit is fitted. Do not pump liquids outside pH 5–9 (such as concrete wash-out water), flammable, oily or chemical liquids; for liquids above 40 °C, order the high-temperature version.
Wear parts and routine checks
- Main wear parts: impeller, suction cover, mechanical seals and the two oil seals. With long running in sandy water, the impeller and suction cover gradually wear and flow drops.
- Regularly check the oil in the oil chamber (turbine oil ISO VG32, 6,500 ml) and the clearance between the impeller and the suction cover. If the oil is cloudy, milky or contains water, have the shaft seals inspected promptly.
