Explore our cutting-edge three-phase induction, explosion-proof, and synchronous permanent magnet motor systems.
Authorized Global Distributor of WOLONG Electric Drive Group
Founded in 1984 and listed on the Shanghai Stock Exchange in 2002 (Code: SH600580), Wolong Electric Drive Group has grown into the world's leading manufacturer of electric motors and drive systems. With 3 major manufacturing bases, 39 advanced factories, and 3 global R&D centers, Wolong delivers unparalleled engineering technology across domestic and international markets.
As Wolong's authorized global distributor, Shaanxi Nanfang Motor Technology Co., Ltd. provides direct access to state-of-the-art three-phase slip ring motors, explosion-proof systems, and high-voltage solutions. We are dedicated to providing optimal drive packages, custom OEM modifications, and full-lifecycle technical support to ensure your heavy-duty machinery operates with high reliability and maximum efficiency.
Request Technical ConsultationDriving global industries forward with localized supply chains and robust, certified electrical engineering expertise.
Fulfilling complex application requirements across hazardous zones, high-torque systems, and energy-efficient parameters.
Our motors hold premium global explosion-proof certifications. Built to withstand explosive atmospheres in coal mining, offshore oil rigs, and petrochemical plants.
Engineered for low power consumption, compliant with standard and high-efficiency ratings (IE3, IE4, IE5). We supply permanent magnet synchronous motors (PMSM) for optimized energy footprints.
Comprehensive AC motor catalog ranging from low-voltage asynchronous units to ultra-high-voltage wound rotor (slip ring) induction motors designed for heavy industrial shafts.
A deep look into the structural elements that make Wolong motors exceptionally durable under extreme mechanical stress.
Our standard three-phase induction motors utilize a robust squirrel-cage design. These rotors are manufactured using centrifugal aluminum casting or die-casting techniques, ensuring a single-piece construction that integrates the rotor bars and end rings. This ensures high structural integrity and reliable starting torque parameters.
For high-capacity three-phase slip ring motors (wound rotor), we employ copper bar rotors with copper alloy slip rings and high-precision brush holders. Slip ring assemblies allow for external resistance integration to manage high starting current constraints and control starting torque during massive inertial load operations (such as in crushers and grinding mills).
The stator coils are crafted with high-purity copper wires wrapped in polyester film and reinforced with premium glass-mica tapes. Following insertion into the magnetic slots, the entire assembly undergoes the Vacuum Pressure Impregnation (VPI) process.
This process completely eliminates air voids inside the windings, sealing the stator in a solid, void-free block. The resulting insulation system boasts exceptional electrical resistance, high mechanical strength, moisture protection, and thermal stability compliant with Class F and Class H thermal rating guidelines.
Developed using our multi-physics simulation platform, the motor frames utilize high-grade structural cast iron or fabricated steel plates. The frame geometry features optimized cooling rib configurations to accelerate thermal heat dissipation.
Engineered with generous structural redundancy, the housing provides exceptional vibration absorption, low structural resonance, and the ability to withstand high mechanical shocks commonly found in harsh underground mining and cement production mills.
The air cooling system features a compact, low-noise fan cover body, air guiding cylinder, protective window, and structural silencer plates. The optimized side air inlets minimize airflow restriction and structural turbulence behind the motor frame.
By integrating state-of-the-art acoustic absorbing liners, the overall noise level is significantly reduced. This protective fan hood is rated up to IP22 or IP23, preventing accidental human contact with high-speed cooling impellers while ensuring maximum ventilation flow.
Through strategic global acquisitions, Wolong has integrated century-old expertise and world-leading industrial motor brands.
Wolong acquired a 97.94% stake in the Austrian ATB Group, one of the three major European motor manufacturers. The acquisition integrated the prestigious brands Morley (underground mining motors) and Laurence Scott (custom low-starting-current marine and nuclear power plant generators), expanding Wolong's reach in Western Europe and heavy industrial mining markets.
Brook Crompton brought over a century of electric motor design expertise to the Wolong group. Renowned for its premium "W" and "10" series low-voltage and medium-voltage motors, Brook Crompton specializes in highly customizable variable-speed drive packages for hazardous and harsh industrial processing lines.
Dating back to 1882, Germany's Schorch represents the gold standard for heavy-duty industrial electric motors. Specializing in customized large machines, high-voltage drive systems, and complex tunnel, shipbuilding, petrochemical, and municipal water management projects.
As the global market leader in industrial vibration motors (MVE) and high-precision vibration sensors, OLI partnered with Wolong in China in 1999, creating a dominant force in bulk material handling, screening, and concrete compaction applications.
As China's largest scientific research and manufacturing base for explosion-proof electric motors, CNE joined Wolong to consolidate domestic and international leadership in hazardous area machinery. CNE motors power critical processes in nuclear reactors, petrochemical plants, and oil extraction.
Wolong integrated GE's commercial and industrial motor division, gaining access to GE's century-long legacy in heavy industries. This partnership strengthened Wolong's presence in North America with high-capacity equipment for mining, metal smelting, and water treatment utilities.
Driving the evolution of heavy-duty induction motors through advanced digitization, efficiency optimization, and smart wear diagnostics.
Future iterations of our 3-phase slip ring motors feature embedded thermal and optical sensors within the slip ring housing. These sensors detect early carbon brush wear, brush-sparking intensity, and rotor temperature rise, sending real-time telemetry to central SCADA systems via Modbus/TCP or OPC-UA protocols.
By bridging classic liquid resistance starters (LRS) with modern variable frequency drives (VFD), Wolong is pioneering hybrid slip ring configurations. The system starts the motor with high torque via an LRS, then switches to a slip-recovery drive (static Scherbius system) to feed rotor energy back into the grid, saving up to 15% in operational energy costs.
Aligning with carbon-neutral targets, Wolong's R&D centers are redesigning core magnetic topologies to reduce active steel and copper volume. We utilize organic, hazard-free varnish coatings and optimize air duct pathways to reduce friction and acoustic drag, lowering emissions and lifecycle carbon impacts.
WOLONG's high-capacity three-phase slip ring motors power essential global infrastructure and heavy processing industries.
For large-capacity ball mills, rock crushers, and mine winders, slip ring motors provide high starting torque under load without grid voltage drops. They withstand abrasive dust, moisture, and high starting loads typical of mining environments.
Cement rotary kilns and heavy clinker crushers require steady startup curves to protect gearboxes and mechanical couplers. Our slip ring motors work with liquid resistance starters to deliver smooth acceleration, protecting downstream equipment.
For high-volume wastewater pumps and water supply stations, Wolong provides heavy-duty slip ring motors that handle variable load profiles and grid fluctuations, ensuring reliable public utility performance.
Automated precision manufacturing for dependable global delivery schedules.
Our domestic production facilities are built on smart manufacturing models. From automated CNC steel plate laminators to advanced coil winding robots, we maintain high dimensional accuracy and process control. Our integrated VPI paint system, automated rotor dynamic balancers, and multi-channel dynamometers test motor performance under full load simulation.
With an established raw material supply chain (copper, high-grade silicon steel, custom cast iron) based in China, we protect customers from international market volatility. This vertical integration allows us to offer short lead times, competitive pricing, and custom OEM frame designs, helping you manage project timelines and costs.
Ensuring compliance, high reliability, and low total cost of ownership (TCO) for global procurement professionals.
Specify critical design parameters, including rated voltage (up to 13.8kV), starting torque multipliers ($T_st/T_n$), rotor voltage ($V_r$), cooling methods (IC611, IC81W, or IC01), and IP sealing codes (IP55/IP56/IP65).
All motor orders undergo routine factory testing. Type tests, witness testing (including thermal rise tests and full load vibration checks), and third-party inspection certifications (SGS, TÜV) are available upon request.
Our motors are covered by standard international warranties, supported by local service networks across North America, Europe, Asia-Pacific, and South Africa. We also provide direct shipment of carbon brushes and slip ring assemblies.
A look at the certifications that verify the safety and performance of Wolong motors in global markets.
Nemko / ATEX
CSA
CE
CCC
SABS
TESTSAFE
To help you navigate international trade requirements, Wolong maintains certification compliance across major global markets:
Explore our high-voltage wound rotor (slip ring) induction motors, marine-duty systems, and fire-resistant industrial solutions.
Detailed technical answers regarding the deployment, operation, and advantages of three-phase slip ring motors.
The primary advantage of a 3-phase slip ring (wound rotor) motor is its ability to deliver high starting torque while maintaining low starting current. By connecting an external variable resistor (or liquid resistance starter) to the rotor circuit via the slip rings, operators can control the torque-slip characteristics during startup. This makes them suitable for starting high-inertia loads like crushers, grinders, and heavy conveyor belts without causing electrical disturbances on the grid.
Slip ring motors require periodic maintenance of the carbon brushes, brush holders, and slip rings. This includes monitoring carbon brush wear, maintaining correct spring tension on the brushes, and cleaning carbon dust to prevent electrical tracking. Our modern slip ring enclosures are designed for easy access and can be equipped with wear-monitoring sensors to support predictive maintenance.
Yes, our slip ring motors can be configured for VFD operation. They are compatible with static slip energy recovery systems (Scherbius drives), which capture slip power from the rotor circuit and feed it back into the supply line, improving overall system efficiency during speed-regulated operation.
Through our dedicated explosion-proof research facility (Nanyang Explosion-Proof Group - CNE), we construct motor housings and terminal boxes to contain internal ignition risks. Our explosion-proof motors are certified under international ATEX, IECEx, and EAC standards, verifying they meet requirements for hazardous Zone 1, Zone 2, Zone 21, and Zone 22 applications.
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