MR52 / MR52ZZ / MR52-2RS Ultra-Miniature Ball Bearing (2mm x 5mm x 2mm / 2.5mm)

Product Overview

High-Precision MR52 / MR52ZZ / MR52-2RS Ultra-Miniature Deep Groove Ball Bearing

The MR52 / MR52ZZ / MR52-2RS Ultra-Miniature Ball Bearing is a metric single-row thin-section deep groove ball bearing engineered for high-precision, low-vibration, and extreme-speed rotary applications. Featuring an inner bore size of 2.0mm and an outer diameter of 5.0mm, the MR52 series is offered in two standard width configurations: 2.0mm for the unshielded Open design and 2.5mm for the dual metal-shielded MR52ZZ / rubber-sealed MR52-2RS variants.

High-Grade Chrome Steel & Contamination Protection

Manufactured from high-carbon chromium bearing steel (GCr15 / AISI 52100), the inner ring, outer ring, and precision micro balls undergo specialized thermal heat treatment to achieve high surface hardness (HRC 60-65) and structural fatigue strength. For clean environments requiring maximum rotational efficiency, the Open model provides minimal friction, while the MR52ZZ metal-shielded and MR52-2RS rubber-sealed versions retain factory grease and shield raceways against ambient dust, liquids, and foreign particulates.

Ultra-Low Friction & Extreme RPM Capability

Equipped with precision-honed raceway grooves and a balanced ribbon cage, the MR52 bearing achieves exceptional rotational speeds up to 100,000 RPM under oil lubrication. Its sub-micron dimensional tolerances ensure smooth radial guidance and minimal axial play in micro-spindle assemblies.

Custom Manufacturing & Material Options

To support specialized industrial and OEM application environments, custom configurations are available upon request:

• Stainless Steel Options: Stainless steel (SUS440C / SUS304) construction for damp, corrosive, or medical-grade environments.
• Flanged Ring Design: Flanged outer ring model (MF52 / MF52ZZ) available for simplified housing mounting and axial location.
• Ceramic Hybrid Options: Silicon nitride (Si3N4) ceramic ball options for ultra-high-speed, low-inertia performance.
• Precision Grading: Available in ABEC-1, ABEC-3, ABEC-5, and ABEC-7 tolerance classes.

Technical Specifications

Key Features

Applications