Explore our standard and highly specialized OEM/ODM asynchronous motor ranges configured for volatile gas, vapor, and combustible dust environments.
Shaanxi Nanfang Motor Technology Co., Ltd. stands as the authoritative global distributor of Wolong (Wolong Electric Drive Group Co., Ltd.). Founded in 1984 and listed on the Shanghai Stock Exchange in 2002 (code SH600580), Wolong has advanced to become a dominant force in the global manufacturing of heavy machinery electric drives, induction motors, and digital control mechanisms.
Through years of systematic international integration, Wolong operates a massive network comprising 3 key international manufacturing bases, 39 advanced manufacturing factories, and 3 global R&D engineering units. The company has created an expansive supply footprint providing highly customized explosion-proof machinery to EPC contractors, system integrators, and industrial distributors across every hemisphere.
Production Lines Worldwide
Countries Active Footprint
Core Engineering Patents
Large-Scale Megawatt Projects
In highly regulated heavy industries, purchasing managers face intense compliance, safety, and operational challenges when sourcing hazardous-area equipment.
Safety is the primary consideration in chemical processing, oil & gas refining, and underground coal mining. Specifying explosion-proof (Ex) induction motors is not merely an engineering option; it is a critical regulatory requirement. Plant managers, engineering, procurement, and construction (EPC) companies, and safety inspectors demand systems that completely mitigate the risk of internal electric arcs, high skin temperatures, or electrical friction initiating combustion in volatile ambient environments.
OEM Ex Induction Motors must satisfy three essential procurement criteria to ensure long-term operational viability and site safety:
Providing global heavy industry with certified, high-efficiency, and customized electric motor technologies.
We provide full compliance structures for global hazardous zones. Whether you operate under European ATEX directives, global IECEx frameworks, North American CSA, Eurasian EAC, South African SABS, or Australian TestSafe guidelines, we offer verified protection profiles.
Supporting corporate carbon reduction targets with IE3, IE4, and advanced IE5 efficiency ratings. Our permanent magnet synchronous motors (PMSM) reduce electrical losses by up to 30%, lowering total cost of ownership across 24/7 operating cycles.
From low-voltage auxiliary pump drives to massive high-voltage positive pressure (Ex p) main compressors, our designs scale up to 10kV+ applications, serving variable speed, mining conveyor, and tunnel boring requirements.
Combining over a century of European and American electric motor manufacturing heritage under Wolong's global technology platform.
In 2011, Wolong successfully acquired 97.94% of the Austrian ATB Group, one of Europe's top three motor manufacturers. This acquisition integrated ATB's century of technology with Wolong's production capacity. ATB brought two highly respected brands into the fold:
Morley Motors: Boasting a 130-year history linked to underground coal mining. Morley is a global benchmark for mine motors, offering underground mining operations equipment built for high specifications, durability, and reliable safety performance.
Laurence Scott: Known for designing motors with low starting currents, Laurence Scott has supplied safety-critical motors for British nuclear power plants and military naval vessels. Under Wolong, Laurence Scott's engineering group has won the Queen's Award for Enterprise for three consecutive years.
Brook Crompton: With over a century of motor design history, Brook Crompton is a pioneer in high-efficiency electric motors. The brand joined the Wolong Group, bringing its premium Brook Crompton "W" and "10" series low, medium, and high-voltage AC motors. This enables the group to deliver comprehensive drive solutions that maintain efficiency in harsh environments.
Schorch: Established in Germany in 1882, Schorch joined Wolong in 2011. The company specializes in heavy industrial drive systems, offering engineering solutions for water transmission, petrochemical processing, pipeline transportation, ship propulsion, and tunnel ventilation.
OLI Vibration Motors: Since 1999, Wolong has partnered with OLI, a global leader in electric vibration technology. This partnership provides access to robust MVE-series vibration motors and specialized Ex-certified vibration sensors designed for industrial flow aid applications.
General Electric (GE) Industrial Motors Partnership (2018): In 2018, Wolong entered into a strategic transaction with GE. As an established name in industrial electrical machinery, GE supplies sectors like heavy chemicals, water treatment, pulp and paper, mining, and metal processing. This partnership combined GE's North American design experience with Wolong's global manufacturing footprint.
A detailed look at the materials, structural simulation, and manufacturing techniques that ensure safe operation in hazardous environments.
Our rotors use squirrel cage designs with cast aluminum rotors produced by centrifugal casting or high-pressure die-casting. This technique pours molten aluminum directly into the slots of the laminated rotor core, integrating the rotor bars and end rings into a single piece. This structure ensures structural integrity, low rotor resistance, and reliable starting torque.
For high-capacity, high-voltage motors, copper bar rotors are used. These feature welded copper bars and end rings designed to handle thermal expansion and high starting currents. For high-speed applications, protective carbon-fiber or alloy retaining rings prevent bar deformation under centrifugal stress.
The stator coil is insulated using polyester films, glass cloth backing, and high-purity mica tape (using medium or low-powder mica formulations). The entire assembly undergoes a Vacuum Pressure Impregnation (VPI) cycle.
The VPI process extracts air and moisture from the stator slots under vacuum, then injects solventless epoxy resins under pressure. This yields a void-free insulation system that provides heat dissipation, mechanical strength to withstand winding movement, and moisture resistance in wet, corrosive areas.
We use digital simulation platforms to model fluid dynamics, thermal stresses, and electromagnetic fields in the frame. The cast iron or fabricated steel frames are designed with high mechanical safety factors to contain internal explosions without rupturing or venting sparks to the outside.
The external cooling fins are optimized for air flow, minimizing localized hot spots and maintaining surface temperatures within the limits of the motor's Ex temperature classification (T1–T6).
The cooling system includes a fan hood, air guide cylinders, protective screens, and sound-attenuating plates. The side-entry air intake minimizes turbulence and flow resistance around obstructions, reducing acoustic signatures and fan power losses.
Internal sound-absorbing materials reduce high-frequency air noise. The entire assembly meets IP22 finger-safe standards, ensuring operation without compromising the motor's cooling capacity.
Meeting international trade standards and regional safety certifications for seamless deployment.
European Union safety passport for explosive atmospheres.
Compliance with North American safety standards.
Declaration of compliance with EU health and safety directives.
Compulsory certification for Chinese markets.
Standard compliance for South African markets.
Regulatory entry certification for Australian mining sites.
Wolong Group employs a quality assurance system certified to ISO 9001 across all design, procurement, assembly, and testing phases. We utilize these standards to help clients manage regulatory risk:
Meeting the demands of tomorrow's clean energy systems and automated process facilities.
We are transitioning our explosion-proof motor product lines toward IE5 ultra-premium efficiency ratings. By using permanent magnets and synchronous reluctance technology, these motors reduce rotor losses and overall energy usage in continuous-duty applications.
Future Ex motors will integrate intrinsically safe, wireless vibration and temperature sensors. By collecting diagnostic data on bearing wear and winding temperatures, operators can schedule maintenance based on actual condition monitoring, reducing unplanned downtime.
As the green hydrogen economy grows, electrical equipment must be rated for Gas Group IIC (Hydrogen). Our engineering designs focus on gas-tight enclosures, positive-pressure systems, and materials that resist hydrogen embrittlement.
Common questions from engineering departments and procurement specialists regarding explosion-proof induction motors.
Ex d (Flameproof) motors are designed with a robust enclosure capable of withstanding an internal gas explosion without deformation. It prevents internal sparks or flame fronts from escaping through machined joints (flamepaths) to ignite the surrounding atmosphere.
Ex e (Increased Safety) motors focus on preventing the initiation of arcs, sparks, or excessive temperatures. They feature tighter tolerance clearances, high-grade insulation systems, and specific current-limiting protection to ensure that no electrical or mechanical part reaches a temperature that could cause ignition under normal or specified abnormal conditions.
VFD operation introduces harmonic voltages that increase stator iron and rotor losses, raising the motor's operating temperature. Consequently, a motor certified for fixed-frequency grid operation cannot be used with a VFD in hazardous areas unless the VFD-motor combination is certified together.
This certification is achieved through joint type testing or by integrating RTDs inside the windings to shut down the drive if temperatures exceed the designated limit (e.g., T4 limits of 135°C).
HV motors (e.g., 3.3kV, 6.6kV, 10kV) are susceptible to partial discharge within microscopic air voids in the stator slots. The VPI process removes these voids by vacuuming out air and moisture and injecting solventless resin under pressure.
This creates a solid structure with high dielectric strength, low partial discharge levels, moisture protection, and improved thermal conductivity, ensuring safety in hazardous atmospheres.
Different markets require specific certifications for hazardous-area equipment:
High-voltage asynchronous pump motors, permanent magnet synchronous drives, and mining-duty systems built to international specifications.
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