UAASWH-22SMU11 AC Spindle Motor Product Specification

UAASWH-22SMU11 is a medium-high power externally forced air-cooled permanent magnet AC spindle motor manufactured by Yaskawa Electric under the mature UAASWH product series. It is specially developed for medium-large vertical machining centers, heavy-duty CNC lathes, large mold milling machines and heavy-load fixed cutting stations on automated metalworking production lines. The motor is built with high-density laminated silicon steel stator core and premium rare-earth permanent magnet rotor structure, delivering a wide constant-power speed regulation range, stable high low-speed torque output and low-vibration high-speed continuous running performance. It can sustain frequent forward-reverse rotation, long-duration heavy rough cutting and uninterrupted precision finish machining of cast iron, alloy steel and large non-ferrous metal workpieces. Equipped with an independent external blower cooling assembly, the spindle realizes efficient forced convection heat dissipation and effectively prevents unexpected overheat protection shutdown under long-term full-load cutting conditions.

The suffix SMU11 stands for exclusive OEM customized configuration including specially optimized fixed-voltage winding design, built-in multi-turn absolute serial feedback encoder and upgraded heavy-duty reinforced bearing set together with tailor-made dimensional parameters for output shaft, keyway and mounting flange. This customized variant cannot be directly replaced by standard 22-frame universal spindle motors without mechanical modification and full recalibration of servo drive parameters. Original mass production of this model has been discontinued, and available market supplies mainly consist of surplus original unused inventory and professionally refurbished motors that complete factory-standard aging test, dynamic balance calibration and high-pot withstand voltage inspection before equipment maintenance replacement.

UAASWH serves as the base series designation of Yaskawa externally air-cooled AC spindle motor. UA represents AC spindle classification; S refers to high-efficiency optimized laminated stator core design; W denotes standard industrial three-phase winding framework; H stands for lightweight reinforced cast aluminum housing structure. The numeric code 22 corresponds to medium-large frame size with S3 intermittent rated output power of 22kW and S1 continuous rated power of 15kW as core electrical ratings of this specification. Letter S indicates customized winding matching fixed regional industrial grid voltage; M represents built-in high-precision multi-turn absolute serial encoder for position feedback; U means upgraded anti-impact heavy-duty rolling bearing assembly for resisting severe radial and axial cutting loads. The last two digits 11 define exclusive OEM mechanical customization parameters including dedicated output shaft dimension and flat keyway size, unique flange mounting hole layout and fixed pin assignment of aviation connectors for power cable and encoder signal wiring, forming an independent specification differentiated from other regular 22-frame spindle products.

This spindle motor is designed for three-phase industrial AC rated input and must be matched with original Yaskawa dedicated spindle servo driver to construct full-digital vector closed-loop speed and position control system. Its S3 intermittent rated output power reaches 22kW while S1 continuous power is 15kW with corresponding rated operating current matching medium-to-heavy cutting load requirements, and the motor can deliver up to three times instantaneous peak overload torque to absorb transient impact load generated during deep rough machining of thick ferrous and alloy blanks. The built-in M-type multi-turn absolute encoder defined by SMU coding continuously transmits real-time rotational speed and absolute angular position digital serial signals to paired servo drive unit, supporting core CNC functions including high-precision rigid tapping, automatic spindle orientation positioning and constant peripheral speed cutting required for large mold and heavy component precision machining.

Stator winding complies with Class F international insulation standard with embedded built-in thermal sensing elements; once sustained abnormal overload triggers winding overtemperature, the matched drive receives temperature alarm signals and automatically executes output derating or protective power cutoff to avoid permanent winding burnout damage. Internal circuit integrates surge suppression components to restrain voltage spikes and electromagnetic interference induced by peripheral frequency converters and switching power devices, securing stable operation under fluctuating factory power grid environments. The motor carries IP54 protection grade for effective dust and cutting fluid splash prevention.

The motor main housing adopts integrated high-strength cast aluminum alloy construction with IP54 dustproof and splash-proof rating, cooperating with split independent external cooling fan module for forced air heat dissipation to achieve superior continuous heavy-load thermal performance compared with natural cooling spindle motors. The front end is equipped with solid integral customized output shaft with exclusive SMU11-spec flat keyway for rigid connection with large synchronous belt pulleys, heavy-duty reduction gearboxes or direct-coupled machine tool spindle assemblies; the rear casing reserves fixed installation space for SMU11 exclusive customized aviation plugs following factory fixed pin definition rules for power wiring and encoder signal connection. Standard flange mounting design enables direct bolt fastening onto machine spindle boxes without additional transition fixture machining.

Permitted continuous operating ambient temperature ranges from 0°C to +40°C, while storage temperature spans -20°C to +70°C; applicable working humidity is maintained between 5%RH and 80%RH under non-condensing conditions to prevent internal metal corrosion and circuit short-circuit faults. If installation altitude exceeds 1000 meters above sea level, users must appropriately reduce continuous working load to compensate for degraded heat dissipation efficiency caused by reduced high-altitude air density. The motor withstands conventional industrial vibration within 10Hz to 55Hz frequency range; operation within sites with corrosive gas, accumulated oil mist and conductive metal dust is strictly prohibited to extend the service life of internal bearings, stator winding and precision multi-turn encoder components.

UAASWH-22SMU11 is widely deployed as core spindle driving component for medium-large vertical machining centers, heavy-duty CNC turning centers, oversized mold engraving & milling equipment and fixed heavy-cut stations on automated production lines, suitable for rough and finish machining of thick ferrous metal, large non-ferrous alloy and high-hardness engineering plastic workpieces. During regular maintenance, operators need periodic cleaning of the external cooling fan filter screen to eliminate dust blockage that leads to poor heat dissipation and unexpected over-temperature protection alarms; regular inspection of output shaft bearing lubrication status and aviation connector wiring tightness is required to avoid bearing oil leakage and loose wiring-induced abnormal spindle speed fluctuation.

For breakdown replacement maintenance, original matching multi-turn absolute encoder and SMU11-spec exclusive dedicated power cables must be adopted; mismatched replacement accessories will trigger invalid feedback signals and out-of-control spindle runaway faults. After professional refurbishment, aftermarket spare motors undergo winding high-pot withstand voltage testing, rotating part dynamic balance calibration and full-load continuous aging testing per original factory technical standards before delivery to guarantee consistent performance parameters matching brand-new original products.