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2025-09-18 13:42:01PRS Bearings
Crossed roller bearings are precision bearings designed to handle radial, axial, and moment loads simultaneously in a compact structure. Due to their unique arrangement of cylindrical rollers oriented alternately at right angles, they are widely used in robotics, machine tools, medical equipment, and rotating tables. Correct installation is critical to ensure optimal performance, long service life, and high rotation accuracy. Installing crossed roller bearings requires precision and adherence to specific steps to ensure optimal performance and longevity. Here's a general guide.
Cleanliness is Key: Ensure the housing and shaft surfaces are meticulously clean and free from burrs, dust, or any contaminants. Use a lint-free cloth and a suitable cleaning agent.
Inspect Components: Carefully inspect the bearing, shaft, and housing for any damage, defects, or irregularities.
Gather Tools: You'll need a press, a heating device (induction heater or oil bath), appropriate mandrels or sleeves, a torque wrench, feeler gauges, and assembly lubricant.
Heating (Recommended): For a proper interference fit, the inner ring of the bearing is often heated to expand it. An induction heater is ideal as it provides even heating. Alternatively, an oil bath can be used, but ensure the oil is clean and heated to the recommended temperature (usually around 80-100°C / 176-212°F). Do not exceed 120°C (248°F) unless specified by the manufacturer.
DO NOT use an open flame.
Pressing (if not heated or for slight interference): If heating is not suitable or only a slight interference fit is required, a press can be used. Apply even pressure to the end face of the inner ring using a suitable mandrel or sleeve that contacts the entire inner ring face. Never press on the outer ring when mounting the inner ring.
Align and Slide: Once heated or pressed, carefully slide the inner ring onto the shaft, ensuring it's properly aligned and seated against the shaft shoulder.
Cooling (if applicable): In some cases, the housing might be cooled to shrink it slightly before inserting the outer ring.
Pressing: Using a press, carefully press the outer ring into the housing bore. Ensure you apply even pressure to the end face of the outer ring using a suitable mandrel or sleeve that contacts the entire outer ring face. Never press on the inner ring when mounting the outer ring.
Alignment: Ensure the outer ring is perfectly aligned with the housing bore.
Lubrication: Apply a thin, even layer of the recommended lubricant (grease or oil) to the bearing races and rolling elements. This helps with initial rotation and prevents rust.
Careful Insertion: Gently insert the assembled bearing (or separate inner/outer rings if not pre-assembled) into its final position within the machine or mechanism.
Bolting/Clamping (if applicable): Many crossed roller bearings are secured with bolts or clamps. Tighten these fasteners evenly and to the manufacturer's specified torque. Use a torque wrench to ensure accuracy.
Check for Smooth Rotation: After installation, manually rotate the connected components to ensure the bearing turns smoothly without any binding, excessive friction, or unusual noises.
Radial and Axial Runout: If possible and necessary for your application, check the radial and axial runout of the mounted bearing using dial indicators to ensure it's within specifications.
Preload (if applicable): Some crossed roller bearings require a specific preload to achieve their rated stiffness and accuracy. This is typically achieved by tightening fasteners to a precise torque or by using shims. Refer to the bearing manufacturer's instructions for preload settings.
Documentation: Record the installation date, bearing type, and any other relevant information for future maintenance.
Manufacturer's Instructions: Always refer to the specific installation instructions provided by the crossed roller bearing manufacturer. These instructions will detail specific tolerances, heating temperatures, torque values, and mounting procedures for their particular bearing.
Clean Environment: Perform the installation in as clean an environment as possible to prevent contamination.
Proper Tools: Using the correct tools is crucial to prevent damage to the bearing or other components.
Avoid Impact: Never hammer or impact the bearing directly. This can cause severe damage to the rolling elements and races.
Professional Help: If you are unsure about any step or the process seems too complex, it's best to consult with experienced personnel or the bearing supplier.
Have you learned the installation method and precautions of cross roller bearings? If you have any questions during the installation process, you can write to us for consultation.
