Silent Motor Bearings: KET Automatic Superfinishing Machine

In precision bearing manufacturing, achieving the exact inner and outer dimensions is only the foundation. For applications that require ultra-high speeds and absolute silence—such as electric motors and precision instruments—the microscopic surface finish of the raceway is what dictates success or failure. At Ningbo Kexiang Bearing Technology Co., Ltd. (KET), we achieve this flawless surface through our Automatic Bearing Superfinishing Machine.

According to our strict product process flow diagram, the "Channel super precision" stage, accompanied by full inspection, is a mandatory step that takes place after the initial internal and external groove grinding.

The Science of Superfinishing

Standard grinding wheels, no matter how precise, leave behind microscopic peaks and valleys on the surface of the steel. If left untreated, the steel balls will bounce across these ridges at high speeds, generating friction, heat, and audible noise.

The Automatic Bearing Superfinishing Machine eliminates these imperfections through a highly specialized process:

• Superfinishing Oilstone Application: The machine presses a finely graded, specialized abrasive oilstone directly against the inner and outer ring raceways (grooves).
• High-Frequency Vibration Friction: The oilstone applies a high-frequency oscillatory vibration combined with rotational friction. This cross-hatching action effectively slices off the microscopic peaks left by previous grinding steps.
• Mirror-Like Finish: The result is an exceptionally smooth, mirror-like raceway surface that maximizes the contact area for the rolling elements and the lubricating grease.

The Decisive Factor for Motor Bearings (Z & V Groups)

Not all bearings are created equal. In the industry, there are exceptionally high requests regarding the vibration of bearings used in electric motors. The Automatic Bearing Superfinishing Machine is the absolute most critical piece of equipment for meeting these demands.

By polishing the raceway to perfection, this machine directly dictates the bearing's final performance classifications:

• Vibration Grades (V-Group): The superfinishing process minimizes the micro-displacement and acceleration of the bearing, allowing it to achieve the strict V1, V2, V3, and V4 vibration grades.
• Noise Grades (Z-Group): By eliminating surface friction, the machine ensures the bearing operates silently, fulfilling the rigorous acoustic requirements of the Z1, Z2, Z3, and Z4 noise groups.

Why Superfinishing Matters to Our B2B Partners

For manufacturers of BLDC motors, medical equipment, and precision UAVs, bearing noise and vibration are unacceptable. By utilizing fully automated superfinishing technology, KET guarantees:

• Acoustic Excellence: Bearings that run silently out of the box, elevating the perceived quality of your final assembled product.
• Enhanced Durability: A smoother raceway reduces localized stress and prevents the breakdown of the lubricant film, exponentially extending the bearing's fatigue life.
• Consistent High-End Quality: Automated high-frequency friction ensures that every single raceway meets the same exacting Z-group and V-group standards.

By perfecting the microscopic details of every raceway, KET ensures our precision miniature bearings deliver the silent, stable, and world-class performance your applications demand.