The ball screw transmission systems of CNC machining centers, precision grinders and automated machine tools bear bidirectional axial loads and radial loads simultaneously during operation. Strict requirements are put forward on axial positioning accuracy and high-speed operation stability of screws. Ordinary single-row angular contact ball bearings can only withstand unidirectional axial force. The installation of two matched bearings involves complicated assembly procedures and high requirements for debugging. Improper assembly easily causes unbalanced preload and rapid accuracy attenuation. Conventional bearing combinations occupy larger installation space and hinder miniaturization transformation of machine tools. High-end precision CNC machine tools urgently need integrated support bearings capable of bearing bidirectional axial force.

Many precision machine tools perform long-term high-speed reciprocating feeding with frequent forward and reverse switching, and alternating loads continuously act on screw supporting positions. Unbalanced internal bearing clearance directly leads to feeding jitter and uneven machining texture, severely damaging surface quality of workpieces. The screw installation space of many new-style machine tools is optimized with compact reserved dimensions, leaving insufficient space for multiple sets of matched bearings. Conventional bearings on the market hardly meet multiple demands including high-speed operation, bidirectional load bearing, high positioning accuracy and limited installation space. The precision machine tool manufacturing industry needs bidirectional angular contact ball bearings to solve load bearing problems on ball screw supporting positions.

NMT Precision Double-Direction Angular Contact Ball Bearings adopt integrated double raceway structure. A single bearing can bear bidirectional axial loads and radial composite loads, eliminating matching and debugging work for two single-row bearings and greatly simplifying mechanical structures of screw supports. Balls and raceways are processed via ultra-precision grinding to realize stable preload, low vibration during high-speed rotation and excellent repeatability of axial positioning, adapting to continuous reciprocating high-speed feeding working conditions of machine tool ball screws. Inner and outer rings adopt standardized dimensions for simple installation and direct replacement of traditional matched bearing schemes.

Balls, inner and outer rings are made of high-purity bearing alloy steel. Precision forging optimizes metal structure followed by rough grinding, finish grinding and mirror superfinishing to meet precision standards on raceway profile accuracy and surface finish. All components receive deep quenching heat treatment and long-term low-temperature stabilization treatment to reduce dimensional variation under high-speed alternating loads and restrain accuracy drift during long-term high-speed operation. Balls are sorted at micron-level precision with uniform dimensions to distribute loads evenly and avoid local stress concentration. The improved cage guides balls smoothly and reserves sufficient lubrication gaps to ensure continuous lubrication under high-speed conditions.

The bearings cover abundant specifications with excellent interchangeability. Widely used in ball screw supporting parts of CNC machining centers, precision internal and external grinders, automated engraving equipment, semiconductor precision transmission modules and CNC lathes, satisfying bidirectional high-precision positioning support demands of precision transmission systems.

Core Product Advantages

Integrated double raceway design enables a single bearing to bear bidirectional axial loads and radial loads and simplify mechanical assembly structures;

Matching and debugging of two bearings are no longer required, reducing manual assembly errors and shortening assembly and debugging time;

Ultra-precision ground raceways realize low vibration and noise during high-speed rotation with stable feeding motion to guarantee workpiece machining precision;

Stable preload prevents clearance expansion under long-term reciprocating switching and maintains consistent positioning accuracy;

Standard outline dimensions are directly compatible with most screw supports for convenient replacement in new and old machine tool renovation;

Long-term stabilized heat treatment for components delivers outstanding fatigue resistance under high-speed alternating loads and extended precision retention cycle;

Optimized cage guiding structure reduces ball friction resistance under high speed and restrains overheating;

Multiple precision grades are optional, covering general automation equipment to high-end precision processing machine tools.

Typical Application Scenarios

Three-axis ball screw supports of CNC machining centers; feed transmission mechanisms of precision grinders and honing machines; screw support units of CNC lathes and turn-milling composite machine tools; transmission parts of high-speed engravers and automated precision carving equipment; precision feed modules of semiconductor packaging equipment; adjusting screw supports of optical inspection instruments; transmission systems of small precision automated tooling.

Quality Assurance

NMT Precision Double-Direction Angular Contact Ball Bearings are manufactured from premium refined bearing alloy steel. Incoming chemical composition inspection and metallographic sampling tests eliminate raw material defects at source. Inner and outer ring blanks are formed by precision hot forging to optimize internal metal flow lines and improve fatigue resistance of rolling contact surfaces. Stress relief annealing is conducted after rough machining to remove internal stress generated in forging and cutting and slow down dimensional drift during long-term operation. Multi-stage grinding and mirror superfinishing are carried out on raceway surfaces with strict control over profile tolerance and surface roughness.

All balls go through dimensional sorting and flaw detection to remove spheres with collision defects. All components undergo high-pressure cleaning and dust-free drying before assembly in constant-temperature clean workshops. Lubricating grease is selected according to operating speed. Finished products complete high-speed durability tests, axial positioning repeatability inspection and alternating load simulation tests. All unqualified products are rejected completely to guarantee precision consistency of bulk goods and provide high-performance support solutions for precision CNC transmission equipment.

Product Range

Standard precision bidirectional angular contact ball bearings, high-speed precision bidirectional angular contact ball bearings, dustproof sealed bidirectional angular contact ball bearings. Selection depends on rotating speed, precision grade and service environment.

Brand Strength

NMT specializes in R&D and manufacturing of precision machine tool bearings. Targeting industry pain points of CNC equipment including bidirectional force bearing of ball screws, high-speed reciprocating switching and long-term maintenance of high precision, NMT continuously optimizes double raceway processing technology, thermal stabilization techniques and rolling element matching schemes. The bearings effectively solve common problems of traditional matched bearings such as complicated assembly, difficult preload control and rapid precision decline after long service. NMT products support stable high-precision feeding and machining of precision machine tools and extend maintenance cycles of transmission components.