ER31 Double Sealed Ball Bearing User Manual

1. Introduction

This manual provides essential information for the proper installation, operation, and maintenance of the Nice ER31 Double Sealed Ball Bearing. Understanding and following these guidelines will ensure optimal performance, longevity, and safe operation of the bearing in your application.

The Nice ER31 is a single-row radial ball bearing designed for applications requiring support for medium radial loads and operating at speeds up to 5000 RPM. It features an extended inner ring with set screws for improved shaft support and synthetic rubber seals with steel shields to protect against contaminants.

2. Safety Information

Always observe standard safety precautions when handling and installing bearings. Failure to do so may result in injury or damage to equipment.

• Wear appropriate personal protective equipment (PPE), including safety glasses and gloves.
• Ensure machinery is de-energized and locked out before installation or maintenance.
• Handle bearings with clean hands or gloves to prevent contamination.
• Do not apply excessive force during installation that could damage the bearing.
• Store bearings in a clean, dry environment to prevent corrosion and contamination.

3. Product Overview and Features

The Nice ER31 ball bearing is engineered for durability and performance in various industrial and commercial applications. Key features include:

• Single-row radial design: Optimized for medium radial loads.
• Extended inner ring with set screws: Provides enhanced shaft support and simplifies installation by eliminating the need for additional spacers.
• Nylon cage: Ensures even spacing of balls, reducing friction, vibration, and noise during operation.
• 52100 Bearing Quality Steel: Through-hardened for superior wear resistance and extended service life.
• Double Sealed: Synthetic rubber seals with steel shields on both sides ride in a labyrinth groove, effectively keeping lubricant in and contaminants out.

Figure 3.1: Front view of the Nice ER31 Double Sealed Ball Bearing, showing the extended inner ring and sealed design.

Figure 3.2: Side view of the Nice ER31 Double Sealed Ball Bearing, highlighting the double seals and set screws on the inner ring.

4. Specifications

5. Setup and Installation

Proper installation is crucial for the performance and lifespan of the bearing. Follow these general steps:

1. Preparation: Ensure the shaft and housing bore are clean, free of burrs, and within specified tolerances.
2. Mounting:
   • For press-fit applications, apply even pressure to the inner ring face. Never strike the outer ring or seals.
   • For slip-fit applications, slide the bearing onto the shaft.
3. Securing (Extended Inner Ring): The ER31 features an extended inner ring with set screws. Once the bearing is positioned on the shaft, tighten the set screws evenly and securely to prevent rotation and axial movement. Refer to equipment-specific torque specifications if available.
4. Alignment: Ensure proper alignment of the bearing with mating components to prevent premature wear and excessive loads.
5. Lubrication: The ER31 is pre-lubricated and double-sealed at the factory. No initial lubrication is required.

Note: For specific machinery, always consult the equipment manufacturer's installation manual.

6. Operating Principles

The Nice ER31 ball bearing operates by utilizing rolling elements (balls) to maintain separation between moving parts, thereby reducing rotational friction and supporting radial loads. The internal design, including the nylon cage and precision-ground raceways, contributes to smooth, quiet operation and efficient power transmission.

The double seals are designed to retain the factory-applied lubricant and prevent the ingress of dust, dirt, and moisture, which are common contaminants in industrial environments. This sealing mechanism is crucial for maintaining the bearing's internal cleanliness and extending its operational life.

7. Maintenance

The ER31 bearing is designed for low maintenance due to its double-sealed, pre-lubricated nature. However, periodic inspection is recommended.

• Inspection: Regularly inspect the bearing for signs of wear, damage, or unusual noise/vibration. Check the integrity of the seals.
• Cleaning: Keep the external surfaces of the bearing and surrounding area clean to prevent contaminant buildup around the seals. Do not use high-pressure washers directly on the seals.
• Lubrication: As a sealed bearing, the ER31 typically does not require re-lubrication under normal operating conditions. If the seals are compromised or the bearing is subjected to extreme conditions, consult a bearing specialist for advice on re-lubrication.
• Replacement: Replace the bearing if significant wear, damage, or excessive noise/vibration is detected.

8. Troubleshooting

Common issues and potential causes for ball bearings:

If issues persist, consult a qualified technician or the bearing manufacturer.

9. Warranty and Support

For information regarding product warranty, technical support, or service, please contact Nice or RBC Bearings directly through their official channels. Keep your purchase receipt and product details (model number, date of purchase) readily available when seeking support.

RBC Bearings, the manufacturer, was founded in 1919 and is headquartered in Oxford, CT. They meet International Organization for Standardization (ISO) standards 9001:2008 and ISO/TS 16949:2009.