How to analyze and troubleshoot a brushless motor motor manual stator slot wedge machine?
The following is a systematic fault analysis and troubleshooting method for brushless motor manual stator slot wedge machine, combined with the characteristics of the equipment and the actual operation and maintenance scenarios, divided into four steps of operation:
I. Fault classification and rapid localization
1. Mechanical faults
Phenomenon:
Slot wedge insertion is not in place (offset, skew)
Stuck handle operation or excessive resistance
Equipment running noise (friction, metal impact sound)
Possible causes:
Wear and tear of transmission parts (gear missing teeth, chain slack)
Positioning guides are shifted or corroded (refer to Summary 3 for guide alignment specifications)
Bearing lubrication failure (dry friction causing seizing)
Slot wedge size does not match stator slots (e.g., more than 0.5mm width difference).
2. Electrical faults
Phenomenon:
The equipment can not start or suddenly stop
The control panel displays abnormal codes (such as E01 overload alarm).
Motor overheating (temperature > 80 ℃)
Possible causes:
Poor wire contact (loose plug, broken wire)
Relay / contactor contacts are corroded (refer to Summary 7 for contact resistance test criteria)
Overload protector malfunction (load current exceeds 20% of rated value)
3. Operational malfunctions
Phenomenon:
Slot wedge breakage rate >5% (edge cracking, delamination)
Stator core scratches (surface visible depth ≥ 0.1mm scratches)
Possible causes:
Operating angle deviation (hand-held tools and grooves are not perpendicular)
Excessive downforce (exceeding the nominal value of the equipment by 50N・m)
Failure to use a guiding jig (e.g. stator positioning jig as mentioned in Summary 10).
Troubleshooting process
1、Preliminary investigation (completed within 5 minutes):
Power failure check: Confirm the status of power switch and emergency stop button.
Manual test: Crank the handle without load, feel whether the resistance is uniform (normal resistance <10N・m).
Visual inspection: check the debris left on the guide rail or mold by the slot wedge (to determine whether the material does not match).
2、Specialized testing (tools: multimeter, vernier calipers):
Electrical inspection: Measure the balance of three-phase current of the motor (deviation should be <10%).
Mechanical accuracy test: check the gap between the positioning block and the stator slot with a plug ruler (allowable error ± 0.05mm).
Material suitability test: Sample measurement of slot wedge size (width tolerance ±0.1mm, thickness ±0.05mm).
3. Data comparison:
Record the current parameters (such as insertion speed, pressure value) and compare with the nominal value of the equipment nameplate.
Comparison of historical maintenance records, identify high-frequency failure points (such as a certain type of groove wedge 3 consecutive breaks need to check the mold).
Typical troubleshooting examples
Case 1: slot wedge inserted after the pop-up
Possible causes:
Slot wedge and slot with too loose (gap> 0.3mm)
Mold spring force is not enough (spring force <15N)
Solution steps:
Replace the high-precision slot wedge (choose the tolerance class IT7 or above)
Adjust the spring preload to 20-25N (refer to Summary 12 for spring force test method).
Apply a small amount of silicone grease to reduce friction (non-insulated parts only).
Case 2: Abnormal vibration during operation
Possible cause:
Spindle dynamic unbalance (eccentricity > 0.02mm)
Loose ground bolts (leveling deviation >1°)
Solution Steps:
Correct the spindle with a dynamic balancer (residual unbalance ≤5g・mm/kg).
Re-level the equipment and lock the bolts (level meter reading ≤ 0.5°)
Install shock absorbing pads (Shore hardness 60-70 rubber pads are recommended).
Preventive maintenance recommendations
Periodic maintenance:
After every 500 operations: clean the guide rail and apply molybdenum disulfide grease (temperature resistance ≥ 200 ℃)
Quarterly: test the insulation resistance of the motor (≥100MΩ, test voltage 500VDC)
Improvement measures:
Carry out surface hardening treatment (e.g. nitriding, hardness HRC55-60) on frequently damaged slot wedge molds
Install photoelectric sensors at the feed opening to monitor the slot wedge in place in real time (refer to the sensing program in Summary 15)
Personnel training:
Operators need to pass the torque control test (error <±5%)
Regular rehearsal of emergency handling procedures (in case of jamming immediately reverse the operating handle to unlock)
Through the above systematic analysis, equipment downtime can be reduced by more than 60%, while reducing maintenance costs.
※ If you still can't solve the equipment failure through the above ways and means, please contact the technical specialist of Xinhui Electromechanical Equipment Co.
