1. Burrs
1.1 Description
Burrs: Small, unwanted projections of material that form along the edges of the gear teeth during the cutting process.
1.2 Causes
Improper Cutting Parameters: Inadequate feed rates, cutting speeds, or depth of cut.
Tool Wear: Worn hobs or dull cutting edges.
Material Properties: Brittle materials are more prone to burr formation.
1.3 Remedies
Proper Cutting Conditions: Optimize cutting speeds, feed rates, and depth of cut.
Tool Maintenance: Regular inspection and replacement of the hob.
Deburring Processes: Implement mechanical or chemical deburring methods post-processing.
2. Chatter Marks
2.1 Description
Chatter Marks: Wavy or uneven patterns on the gear teeth surface caused by vibrations during the cutting process.
2.2 Causes
Machine Vibrations: Inadequate machine rigidity or unstable mounting.
Improper Cutting Parameters: Incorrect feed rates or cutting speeds.
Tool Wear: Blunt or improperly sharpened hobs.
2.3 Remedies
Vibration Control: Improve machine stability and rigidity, use vibration dampeners.
Optimize Cutting Parameters: Adjust feed rates and cutting speeds to minimize vibration.
Tool Maintenance: Ensure that hobs are properly sharpened and regularly inspected.
3. Dimensional Inaccuracy
3.1 Description
Dimensional Inaccuracy: Deviations from specified dimensions in the gear teeth, affecting the gear’s performance.
3.2 Causes
Improper Setup: Incorrect mounting of the gear blank or hob.
Thermal Expansion: Heat generation during cutting causing material expansion.
Machine Wear: Wear and tear on the machine components affecting precision.
3.3 Remedies
Accurate Setup: Ensure precise mounting and alignment of the gear blank and hob.
Temperature Control: Implement cooling systems to manage heat generation.
Machine Maintenance: Regular maintenance of the machine components to reduce wear.
4. Poor Surface Finish
4.1 Description
Poor Surface Finish: Rough or uneven texture on the gear teeth, affecting the gear's performance and lifespan.
4.2 Causes
Tool Wear: Dull or worn hobs causing rough cuts.
Improper Cutting Parameters: Incorrect feed rates or cutting speeds.
Material Properties: Material characteristics that do not support smooth cutting.
4.3 Remedies
Tool Maintenance: Regular sharpening or replacement of hobs.
Optimize Cutting Conditions: Adjust feed rates and cutting speeds to improve surface finish.
Material Selection: Choose materials that support smooth cutting.
5. Tooth Profile Errors
5.1 Description
Tooth Profile Errors: Deviations in the gear tooth shape from the specified profile.
5.2 Causes
Improper Hob Selection: Using hobs unsuitable for the required tooth profile.
Incorrect Machine Settings: Improper settings for feed, speed, or hob positioning.
Machine Deflection: Deflections or vibrations in the machine causing profile distortion.
5.3 Remedies
Proper Hob Selection: Use hobs that match the required tooth profile specifications.
Accurate Machine Settings: Ensure correct machine settings according to gear specifications.
Machine Stiffness: Improve machine stiffness to reduce deflections and vibrations.
6. Gear Runout
6.1 Description
Gear Runout: Axial or radial deviations in the gear’s rotation, leading to irregular motion.
6.2 Causes
Improper Mounting: Incorrect mounting of the gear blank or hob.
Machine Misalignment: Misalignment of the gear blank or hob during the cutting process.
Tool Wear: Worn or damaged hobs causing uneven cuts.
6.3 Remedies
Accurate Mounting: Ensure precise and secure mounting of the gear blank and hob.
Machine Alignment: Regularly check and correct the alignment of machine components.
Tool Maintenance: Use properly maintained and sharp hobs.
Conclusion
Understanding and addressing these common defects in gear hobbing is crucial to producing high-quality gears. Optimizing cutting parameters, ensuring tool and machine maintenance, and proper setup are essential steps to minimize defects and improve the overall quality of the gear hobbing process.
About Zhejiang Toman Intelligent Technology Co., Ltd. (Toman)
Toman is a company that adheres to the strategic vision of to be the leader in the professional field, with the mission of innovation to drive customer value enhancement, and the business philosophy of WISE, ALWAYS KEEP STEP AHEAD. In operation since 2006, the company includes the complete range of gear hobbing machine, gear cutting machine, gear machining compound machine tools, gear shaving machine, automatic production units, automatic turning production lines, and MES manufacturing execution system, etc. TOMAN today, is recognised as an industry leader for machines in China.
Toman cutting machines:
CNC high precision gear hobbing machine, gear chamfering machine, gear shaving machine, gear hobbing machine with integrated chamfering station etc.
-Profitable -Intelligent -Accurate
Our machines are suitable for commercial vehicle gear, passenger vehicle gear, construction machinery gear, especially for the processing of new energy vehicle gear.
For more information about cnc gear cutting machines, please visit our website:
www.zjtoman.com
www.tomanmachines.com
For further information, please contact:
Sharon Gong
Master of Mechanical Engineering
Whatsapp/Wechat: +8613589398142
Mail: sharon@zjtoman.com
Skype: sharon.gong525