Introduction to DDRI-2 Bearings
DDRI-2 bearings are INCH size high-precision miniature ball bearings designed to meet the needs of instrumentation, aerospace, robotics, and other demanding applications. These bearings are part of the inch-sized miniature ball bearing category and are renowned for their versatility, precision, and durability. At BYWB Bearing, we are committed to providing high-quality DDRI-2 bearings that ensure optimal performance for diverse applications.
In this guide, we will explore the specific technology behind DDRI-2 bearings, material options, seal types, common applications, and provide a detailed inch-size bearing size chart to help you select the perfect bearing for your needs.
DDRI-2 Bearing Technology Details
Dimensional Specifications and Technical Parameters
The DDRI-2 Bearing’s standardized dimensions make it versatile for a wide range of applications. Below are its key measurements and load-handling capabilities:
| Specification | Value |
| Inner Diameter (d) | 0.0400 in |
| Outer Diameter (D) | 0.1250 in |
| Width (B) | 0.0781 in |
| Dynamic Load (Cr) | 36 lbf |
| Static Load (Cor) | 10 lbf |
| Precision | ABEC-1,3,5,7 |
| Tolerance | ±0.0003-0 |
| Ball Qty | 6 |
| Available Bearing Types | Flanged, standard |
| Sealed option | Open,ZZ,2RS |
DDRI-2 INTERCHANGE CROSS NUMBER
| BYWB | NMB | DYNAROLL | RMB | FAG | EZO |
| DDRI-2 | DDRI-2 | SR09 | UL1304X | SR0308 | SR09 |
Dimensional Accuracy and Load Capabilities
DDRI-2 bearings are engineered to provide high dimensional accuracy, meeting ABEC-5 or ABEC-7 standards depending on the specific application. Their load capabilities are optimized for both radial and axial forces, making them suitable for dynamic and static load scenarios.
Dynamic Load Rating: Designed to handle applications requiring continuous motion.
Static Load Rating: Suitable for stationary applications where precision alignment is critical.
Noise and Vibration Reduction
The technology behind DDRI-2 bearings incorporates advanced manufacturing techniques to minimize noise and vibration. This is essential for sensitive applications, such as medical devices and precision instruments, where operational quietness is a priority.
Lubrication Options
Proper lubrication is critical for the optimal performance of DDRI-2 bearings. They can be supplied with grease or oil lubrication, depending on the application requirements. For high-speed or low-torque applications, oil lubrication is preferred, while grease is suitable for sealed bearings to reduce maintenance needs. We normally use chevron SRI grease 2# , Temperature Range -86 to 230 °F .
Material Selection for DDRI-2 Bearings
Choosing the right material for DDRI-2 bearings is crucial to ensure optimal performance, longevity, and compatibility with the intended application. The two primary material options for these bearings are chrome steel and stainless steel.
Chrome Steel (SAE 52100)
Chrome steel is the most common material used for DDRI-2 bearings due to its excellent hardness, wear resistance, and cost-effectiveness.
Advantages:
High load-carrying capacity.
Excellent wear and fatigue resistance.
Suitable for applications requiring high precision and speed.
Applications:
Robotics.
Medical instruments.
Aerospace.
Limitations:
Susceptible to corrosion in humid or wet environments.
Stainless Steel (AISI 440C)
440C Stainless steel DDRI-2 bearings are designed for applications where corrosion resistance is critical. They are ideal for environments exposed to moisture, chemicals, or extreme temperatures.
Advantages:
Superior corrosion resistance.
Suitable for food-grade and cleanroom applications.
Low maintenance requirements.
Applications:
Marine equipment.
Pharmaceutical instruments.
Chemical processing machinery.
Limitations:
Lower hardness and load-carrying capacity compared to chrome steel.
Seal Types for DDRI-2 Bearings
The sealing configuration of DDRI-2 bearings plays a vital role in protecting the bearing components from contaminants, ensuring longer service life. Common seal types include open, shielded, and sealed designs.
Open Bearings
Open DDRI-2 bearings do not have any seals or shields, allowing for maximum speed and minimal friction. They are suitable for clean environments where contaminants are not a concern.
Advantages:
Low torque.
Easy lubrication access.
Applications:
Laboratory instruments.
Precision machining tools.
Shielded Bearings (ZZ)
Shielded DDRI-2 bearings feature metal shields on one or both sides to protect against larger particles while allowing some level of airflow.
Advantages:
Better protection against contaminants than open bearings.
Suitable for moderately clean environments.
Applications:
Small Electrical motors.
Office equipment.
Sealed Bearings (RS or 2RS)
Sealed DDRI-2 bearings have rubber or synthetic seals that fully enclose the bearing, offering superior protection against dust, moisture, and other contaminants.
Advantages:
Excellent sealing performance.
Minimal maintenance requirements.
Applications:
Outdoor equipment.
Food processing machinery.
Applications of DDRI-2 Bearings
Due to their precision, durability, and versatile design, DDRI-2 bearings are used in a wide range of industries and applications. Below are some of the most common use cases:
Medical Devices
Miniature ball bearings like DDRI-2 are essential in medical equipment such as dental tools, surgical instruments, and diagnostic machines, where reliability and precision are paramount.
Aerospace
In aerospace applications, DDRI-2 bearings are used in gyroscopes, navigation systems, and control instruments, ensuring accurate performance in extreme conditions.
Robotics
Robotic systems require high-precision components for smooth and efficient operation. DDRI-2 bearings are perfect for robotic joints and actuators due to their compact size and high-speed capability.
Instrumentation
Instruments like pressure gauges, flow meters, and temperature sensors benefit from the low-friction and high-accuracy characteristics of DDRI-2 bearings.
DDRI-2 Inch-Size Bearing Size Chart
Below is a detailed size chart for DDRI-2 bearings to help you select the right bearing for your application:
| Bearing Model | Inner Diameter (in) | Outer Diameter (in) | Width (in) | Shield/Seal Option |
| DDRI-2 | 0.125 | 0.375 | 0.156 | Open, ZZ, 2RS |
| DDRI-2-5 | 0.156 | 0.375 | 0.156 | Open, ZZ, 2RS |
| DDRI-2-7 | 0.187 | 0.500 | 0.196 | Open, ZZ, 2RS |
| DDRI-2-9 | 0.250 | 0.625 | 0.196 | Open, ZZ, 2RS |
Conclusion
DDRI-2 bearings are a cornerstone of miniature ball bearing technology, offering unparalleled precision, versatility, and reliability. Whether you require bearings for medical devices, aerospace instruments, or robotics, DDRI-2 bearings provide a robust solution tailored to your needs.
At BYWB Bearing, we pride ourselves on delivering top-quality DDRI-2 bearings with customizable options for material, seals, and lubrication. Our comprehensive range ensures you can find the perfect bearing for your application.
For more information about DDRI-2 bearings or to request a quote, visit BYWB Bearing. Let us help you achieve unmatched performance in your next project.
