Drives for water management: pumps, hydraulic gates, aeration and dewatering
Water management covers a broad range of process duties — from trunk water-supply pumping stations and sewage pumping stations with submersible units to control of hydraulic gates at hydroelectric and water-intake structures, aeration of wastewater treatment plants and dewatering of sludge. Each duty places its own demands on the drive: trunk pumps need HV motors rated for continuous S1 service, hydraulic gates demand precise positioning and emergency brakes, and slurry pumps in industrial closed-loop water systems must withstand abrasion and cavitation.
Industry-typical tasks
- Trunk and booster water-supply pumping stations rated 200–6,000 kW with 6/10 kV HV motors
- Sewage pumping stations with 15–355 kW submersible pumps for wastewater and sewage transfer
- Hydraulic gates (sluice, radial and regulating) with precise positioning, 5.5–75 kW
- Aeration systems for wastewater treatment plants — 75–500 kW aeration blowers and surface aerator drives
- Rotating biological contactor (RBC) biofilters — low-speed gear motors for continuous duty
- Dewatering decanter centrifuges and 75–450 kW KSM/KSL slurry pumps for treatment-plant sludge
- Slurry pumps for industrial closed-loop water systems — mineral processing plants, metallurgy, thermal power plants
- Auxiliary systems at hydroelectric plants — generator-cooling circulation pumps, drainage sump pumps, hydraulic power units for gate control
Gearboxes and gear motors
In water management, gearboxes operate in three typical modes: continuous long-term duty (biofilters, aerators, dewatered-sludge conveyors), precise positioning (gates and slide gates of hydraulic structures) and drive of aeration blowers and compressors with high reduction ratios. A separate niche covers dewatering equipment: decanter centrifuges and sludge screw conveyors paired with KINGDA's KSM and KSL slurry pumps.
Precise positioning of hydraulic gates
Boneng K- and HB-series gear motors with brake and position feedback drive sluice, radial and regulating gates at hydraulic structures. Stroke positioning accuracy of 0.5–1 mm is delivered by the high reduction ratio (i = 80–200) and a built-in multi-turn encoder. Drive redundancy with a pair of gearboxes on a common shaft is the standard layout for critical gates.
- — Reduction ratio 80–200
- — Built-in electromagnetic brake that engages on loss of power
- — Multi-turn absolute encoder for position monitoring
- — IP66 protection, design rated for submerged installation
Surface aerator drives for wastewater treatment plants
Low-speed Boneng gear motors rated for S1 continuous duty drive surface aerators in biological treatment lines. The low rotor speed (30–60 rpm) and high output torque are produced by a 3- or 4-stage gear train. The cast-iron housing with epoxy coating withstands the corrosive environment (biogas, hydrogen sulphide).
- — Output speed 30–60 rpm
- — Service factor of at least 1.5 for S1 continuous duty
- — Anti-corrosive epoxy coating on the housing
- — Reinforced bearings to take the vertical rotor load
Gearboxes for rotating biological contactor (RBC) biofilters
An ultra-low-speed drive (1–4 rpm) with a high reduction ratio (i = 1,500–6,000). Used on biofilters with partially submerged biodiscs, where 24/7 duty without stoppages and low vibration are required. Boneng R- and HB-series gearboxes paired with a small-power motor of 1.5–7.5 kW.
- — Output speed 1–4 rpm
- — Reduction ratio i = 1,500–6,000
- — S1 continuous duty, service life of at least 80,000 h
- — Low vibration (the biodisc is partially submerged in water)
KINGDA KSM/KSL slurry pumps — sludge dewatering and closed-loop water supply
KINGDA's flagship offering — horizontal centrifugal slurry pumps in the KSM (mid-duty) and KSL (heavy-duty) series with wear-resistant wet ends in high-chrome A05/A49 iron. They handle slurry with up to 60% solids and abrasive content up to 800 mg/l at mineral processing plants, wastewater treatment plants and closed-loop water systems of metallurgy and mining-and-processing operations. Shaft power 75–450 kW, capacity up to 3,000 m³/h.
- — Wear-resistant wet-end materials (A05, A49, rubber)
- — Shaft power 75–450 kW
- — Capacity up to 3,000 m³/h, head up to 100 m
- — Spare-parts kit of replaceable liners and impellers
- — Layout with bearing assembly and gland or mechanical seal
Drive of dewatering centrifuges and screw conveyors
Decanter centrifuges for treatment-plant sludge dewatering run at a rotor speed of 2,500–4,000 rpm and need an accurate differential drive (main plus differential gearbox). Screw conveyors for dewatered sludge are equipped with standard Boneng K-series gear motors fitted with a brake and a Tianiu backstop to prevent reverse rotation on stop.
- — Main drive: HV motor plus belt transmission
- — Centrifuge differential gearbox (planetary, with built-in torque sensor)
- — Screw conveyor: K-series gearbox plus Tianiu backstop
- — Overload protection in case of screw jam
Electric motors
Water-management facilities use three classes of motors: high-voltage units (trunk pumps, treatment-plant aeration blowers) rated 800–6,000 kW at 6/10 kV; special submersible motors for sewage pumping stations in IP68 oil-filled hermetic execution; and general-purpose low-voltage motors for auxiliary drives and compressors. Wolong YHTM and WD3000 cover the HV segment, dedicated submersible series serve sewage pumping stations, and Huali YE/YBX3 cover general-purpose loads.
HV motors for trunk water-supply pumps
Wolong YHTM, WD3000 — high-voltage induction motors 6/10 kV rated 800–6,000 kW for trunk and booster water-supply pumping stations. S1 continuous duty, up to 20 starts per day, nominal efficiency above 96%. Capacity is controlled by a guide vane on the pump or by an HV variable-frequency drive (the discharge-side option delivers up to 30% energy savings).
- — Rated 800–6,000 kW, 6/10 kV
- — S1 continuous duty, service life 80,000 h
- — Bearings with lifetime grease or a forced lubrication system
- — Insulated non-drive-end bearing when operated from an HV inverter
- — IP55 protection, IC411 / IC81W cooling
Submersible motors for sewage pumping stations
Sewage pumping stations with 15–355 kW submersible pumps run fully submerged and must come in IP68 hermetic execution with a double mechanical seal and an oil-filled chamber. Wolong supplies dedicated submersible series with stator-winding thermal protection, chamber moisture sensing and compatibility with frequent starting (up to 20 per hour) driven by level fluctuations in the wet well.
- — IP68 hermetic seal, immersion depth up to 20 m
- — Double mechanical seal with an oil-filled interstitial chamber
- — Winding thermal protection (Pt100 / PTC)
- — Moisture sensor in the interstitial chamber
- — Compatibility with S4 duty (up to 20 starts per hour)
Motors for aeration blowers and compressors
Treatment-plant aeration (75–500 kW) runs in S1 continuous duty around the clock. Multi-stage centrifugal blowers and turbo rotary compressors are typical. The motor operates from an inverter that trims air flow against the dissolved-oxygen reading in the aeration basin. Wolong WD3000 and Huali YE3 / YBX3 are suitable depending on the power rating.
- — Class F insulation with class B thermal margin
- — Inverter-compatible insulation (NEMA MG1 Part 31)
- — Low noise (< 85 dB at 1 m)
- — Bearing protection against shaft currents on VFD operation
General-purpose motors for auxiliary drives
Huali YE3, YBX3, YE4 — general-purpose induction motors 0.75–315 kW in IE3/IE4 efficiency classes for auxiliary drives at treatment plants and pumping stations: dosing pumps, reagent mixers, sludge scraper drives, screw screens and gate drives on secondary flows.
- — IE3 / IE4 efficiency class
- — IP55 protection, class F insulation
- — VFD-compatible for variable-speed operation
- — C3 / C4 anti-corrosive housing coating for wet rooms
Industrial brakes
In water management, brakes perform two critical functions: holding lift-type hydraulic gates at a set position (service brake) and emergency closure on loss of power or a protection trip (emergency brake). Large gates at hydroelectric and water-intake structures use a duplex braking layout — service plus emergency — with each unit sized to 1.75–2.0 times the rated hoist torque. Backstops on dewatered-sludge conveyors prevent belt reversal under the weight of the load.
Brakes for lift-type hydraulic gates — duplex layout
Huawu YPZ2 / YWZ5 — electro-hydraulic disc brakes in a duplex layout on the gate-hoisting winch. The service brake holds the gate at an intermediate position during normal operation; the emergency brake (spring-applied, fail-safe type) engages on loss of power or a protection trip within 0.1–0.2 s — critical to prevent free fall of the gate, which would damage seals and the sill. Used on large hydroelectric and water-intake structures.
- — Duplex set of brakes: service plus emergency
- — Braking torque margin 1.75–2.0 over the rated hoist torque
- — Engagement time on power loss ≤ 0.2 s
- — IP65 protection, ambient −25 to +50 °C
- — Backup power from a UPS or battery bank
Shoe brakes for lock-gate drives
TKT/TKK shoe brakes with an electro-hydraulic thruster are mounted on the low-speed shaft of lock-gate and regulating-gate drives. They hold the load on loss of power and engage smoothly without shock-loading the driveline. Manual release is provided for maintenance and emergency evacuation.
- — Electro-hydraulic thruster Ed-50 to Ed-301
- — Manual release feature
- — Limit switch for lining-wear monitoring
- — Anti-corrosive execution for wet rooms
Backstops for dewatered-sludge conveyors
Tianiu NJ/NJZ overrunning clutches (backstops) are mounted on the low-speed shaft of treatment-plant dewatered-sludge conveyor drives. They prevent belt reversal under the weight of the load when the drive stops or trips. No external power is required — engagement is purely mechanical and triggered by a change in rotation direction.
- — Holding torque margin 1.5 over rated torque
- — Lubrication-free sprag/ratchet mechanism
- — IP55 protection, oil-filled housing
- — GOST certification for use on hydraulic structures
Brakes for sludge scraper and screen drives
Emergency brakes for sludge scraper drives at primary and secondary clarifiers and for screw screens at mechanical pretreatment. They protect the gearbox and scraper from damage on a jam against a large object, engaging on a torque-sensor signal or motor-overcurrent trip.
- — Braking torque 1.5–2.0 times the rated drive torque
- — Engagement time ≤ 0.3 s
- — Compatibility with the treatment-plant PLC system
- — Anti-corrosive coating for humid atmosphere
Couplings and hydraulic power units
Water management uses fluid couplings for large pumps with heavy starts (trunk water mains, slurry pumps in closed-loop industrial water systems), pin-type flexible couplings for general-purpose pumping and aeration drives, and a dedicated class of hydraulic power units for controlling large gates at hydroelectric structures. A Donly hydraulic power unit with high-pressure pumping skids actuates the gate-hoisting cylinders and delivers emergency closure on power failure via pneumo-hydraulic accumulators.
Fluid couplings for large pumps with heavy starts
Jiaohua YOX/COX fluid couplings deliver soft starts on trunk water mains and on slurry pumps in industrial closed-loop water systems. The 2–3% slip at rated operation protects the motor from overload if the impeller jams (for instance, a large object entering a slurry-pump wet end). Versions with a fusible plug release the oil externally on overheating.
- — Rated slip 2–4%
- — Fusible plug rated 145–160 °C
- — Oil fill of 70–85% of internal volume
- — HV-motor flange compatibility
Hydraulic power units for large hydraulic gates
Donly — high-pressure hydraulic power units (16–32 MPa) for actuating hoist cylinders of large hydraulic gates at hydroelectric plants, reservoirs and water-intake structures. Scope of supply: a main and a standby pumping skid, pneumo-hydraulic accumulators for emergency gate closure on power failure, fine-mesh filters, an oil cooler and a PLC control cabinet. The redundant layout keeps the unit running even if one of the skids fails.
- — Operating pressure 16–32 MPa
- — Redundant pumping skids (main plus standby)
- — Pneumo-hydraulic accumulators for emergency gate closure
- — PLC control cabinet with a SCADA interface
- — Compliance with hydraulic-structure requirements
Hydraulic control components — valves, pumps, cylinders
Huade — a Chinese Bosch Rexroth licensee: proportional and servo valves, A4VSO/A11VO axial-piston pumps and custom-built cylinders for hydraulic-structure duty. They are used inside Donly power units and in standalone drives of regulating gates. INI Hydraulic supplies complete medium-pressure power units and components, gear pumps and high-pressure hoses.
- — Proportional valves with position feedback
- — Variable-displacement axial-piston pumps
- — Cylinders with an anti-corrosive rod (chromium or ceramic)
- — Compatibility with HFC / HFDU fluids for fire safety
Pin-type flexible couplings for pump units
Jiaohua YOXp / Yongjing LX — pin-type flexible couplings with elastic bushings between motor and pump. They damp shock loads on start-up, take up small radial misalignments after thermal growth and simplify pump disassembly for service without removing the motor.
- — Torque 0.5–25 kN·m
- — Radial misalignment compensation 0.2–0.8 mm
- — Service life of the elastic elements at least 30,000 h
- — Easy bushing replacement without pulling the hubs off the shafts
Applications gallery
Our solutions for this industry
SDS portfolio brands that cover typical applications in this industry.
- WOLONGHV motors for trunk pumps 800–6,000 kW (YHTM, WD3000) and dedicated submersible series for sewage pumping stations with a double mechanical seal and IP68 rating
- BONENGPrecise-positioning gear motors for hydraulic gates and slide gates (K, HB), and gearboxes for aerators and RBC biofilters
- HUAWUDuplex (service plus emergency) brakes for lift-type gates (YPZ2/YWZ5) and Ed-series electro-hydraulic thrusters for lock-gate drives
- DONLY16–32 MPa hydraulic power units for control of large gates at hydroelectric structures, with redundant pumping skids and pneumo-hydraulic accumulators for emergency closure
- HUADEHydraulic control components — proportional valves, A4VSO/A11VO axial-piston pumps and servo-cylinders for gate-control power units
- INIComplete medium-pressure power units, gear pumps and high-pressure hoses for auxiliary drives at hydraulic structures
- KINGDAKSM (mid-duty) and KSL (heavy-duty) slurry pumps 75–450 kW — flagship solution for treatment-plant sludge dewatering and industrial closed-loop water supply
- JIAOHUAYOX/COX fluid couplings for trunk water mains and closed-loop slurry pumps with heavy starts
- HUALIIE3/IE4 general-purpose motors (YE3, YBX3, YE4) 0.75–315 kW for auxiliary drives at treatment plants and pumping stations
- TIANIUNJ/NJZ overrunning backstops for dewatered-sludge conveyors at treatment plants — preventing belt reversal on stop
- YONGJINGLX pin-type flexible couplings for pump units and aeration drives, compensating for misalignment after thermal growth
- DEOPlate heat exchangers and oil coolers for gate-control power units and lubrication systems of large pumps
Image credits: State Government Photographer (CC0) · SuSanA Secretariat (CC BY 2.0) · CCadio (CC BY 4.0) · SuSanA Secretariat (CC BY 2.0) · Peter Craven (CC BY 2.0)