1 Structural Composition and Working Principle of NMT Screw Support Bearings

Screw support bearings mainly consist of inner rings, outer rings, steel balls, cages, seals and angular contact raceway structures. Their core feature is providing axial rigid support for ball screw assemblies while withstanding axial loads, radial loads and overturning moments.

Japan NMT screw support bearings commonly include thrust angular contact ball bearings, double-direction thrust angular contact ball bearings, combination bearings and high-precision angular contact bearings. Compared with ordinary bearings, screw support bearings emphasize axial rigidity, positioning accuracy, preload stability and low-heat performance. Their core function is to reduce friction, temperature rise, axial play and reversal error during ball screw rotation, feed motion and precision positioning. Screw support bearings are widely used in machining centers, CNC lathes, grinding machines, boring and milling machines, gantry machines and automated linear motion platforms. They are key components affecting machine tool feed accuracy, transmission rigidity and machining stability.

2 Core Performance Advantages of Japan NMT Screw Support Bearings

First, angular contact structure, suitable for combined axial, radial and overturning moment load conditions.

Second, high-precision raceway and steel ball combination provides stable axial positioning, suitable for precision feeding.

Third, high-rigidity design, suitable for heavy cutting, high-speed feed and high-load conditions.

Fourth, optional preload structure allows adjusting bearing condition according to rigidity, speed and accuracy requirements.

Fifth, low-friction design, helping reduce heat generation, torque fluctuation and driving energy consumption.

Sixth, internationally standard mounting dimensions ensure good interchangeability for direct replacement of imported screw support bearings.

3 Main Industrial Application Scenarios of NMT Screw Support Bearings

3.1 Machining Center Screws

Screw support bearings for X/Y/Z axes of vertical machining centers, horizontal machining centers, gantry machining centers and five-axis machining centers.

3.2 CNC Lathe Screws

Screw bearing parts for CNC lathes, turn-mill centers, precision lathes and slant bed lathes.

3.3 Grinding Machine Screws

Feed screw support bearings for cylindrical grinders, internal grinders, surface grinders and high-precision grinding machines.

3.4 Boring and Milling Machine Screws

Screw bearings for jig boring machines, CNC boring and milling machines, precision boring machines and gantry boring and milling machines.

3.5 CNC Rotary Tables

Support bearings for CNC rotary tables, index tables, fourth axes, fifth axes and rotary tables.

3.6 Automated Feed Platforms

Bearings for linear motor platforms, precision slides, automated assembly equipment and inspection equipment feed systems.

4 Model Selection, Assembly and Daily Operation & Maintenance Guidelines

4.1 Key Points for Structure Selection

Load type: thrust angular contact ball bearings for dominant axial loads; combination bearings for combined loads;

precision grade: high precision grade preferred for precision machine tools, grinding machines and CNC rotary tables;

preload grade: heavy preload for heavy cutting; light preload or medium preload for high-speed low-heat applications;

installation method: confirm screw shaft diameter, bearing housing, lock nut, spacer and preload structure;

speed requirement: low-friction high-speed structures preferred for high-speed feed axes.

4.2 Assembly Specifications

Before installation, check that bearings, screw shafts, bearing housings, lock nuts, spacers and mating surfaces are clean, free of burrs, chips and oil contamination.

Ensure coaxiality and axial positioning during screw support bearing installation to avoid raceway damage and accuracy loss caused by uneven loading.

Pay attention to orientation, spacer thickness and preload sequence when installing paired bearings to prevent insufficient axial rigidity or excessive preload.

Apply assembly pressure evenly on the corresponding ring bodies; never press directly on rolling elements and cages.

Keep assembly environment highly clean; fine particles entering the bearing cause raceway pitting, noise and accuracy loss.

4.3 Lubrication Suggestions

High-speed spindle bearing oil or special high-speed bearing grease is recommended for screw support bearings for periodic lubrication replenishment.

Regularly check oil or grease condition and replace when blackened, contaminated, emulsified or with abnormal temperature rise.

Control grease filling quantity for high-speed feed axes to avoid temperature rise and vibration increase caused by overfilling.

Regularly check pressure, flow and pipeline condition in oil-air lubrication, oil mist lubrication and jet lubrication systems.

Do not mix different types of lubricating materials to avoid lubricating film failure.

4.4 Daily Inspection Focus

Monitor screw temperature rise, axial play, reversal error, positioning accuracy and noise changes continuously.

Increased positioning error, abnormal reversal error, rapid temperature rise or abnormal noise in machine tools is commonly caused by insufficient lubrication, improper preload, raceway damage, screw thermal deformation or seal failure.

For high-speed feed axes, temperature rise, vibration and lubrication condition; for precision machine tools and CNC rotary tables,  positioning accuracy, repeat positioning accuracy and backlash.

Regularly check seals, cooling systems, lubrication lines and lock nuts; replace promptly when leakage, blockage or looseness is observed.

Inspect or replace the bearing promptly when abnormal bearing noise, excessive axial play or poor rotation is observed.

5 Import Substitution Value and Supply Chain Advantages of NMT Screw Support Bearings

Manufacturers of CNC machine tools, machining centers, grinding machines and automation equipment often face long lead times for high-precision preloaded screw support bearings, high prices, complex pairing and long maintenance cycles when sourcing imported screw support bearings. Japan NMT screw support bearings are made of high-purity bearing steel with precision raceway machining technology. Their axial rigidity, positioning accuracy, preload stability and low-heat performance match imported products, suitable for new equipment assembly and maintenance replacement.

All products comply with international standard mounting dimension specifications; most sizes can be directly replaced without modifying screw shafts, bearing housings and locking structures. Popular screw support bearing sizes are stocked to quickly fulfill precision machine tool bulk orders and urgent maintenance demands. Streamlined supply chains reduce intermediate costs and control long-term component procurement expenditure for machine tool manufacturing and after-sales service.

Screw support bearings combine high precision, high rigidity, adjustable preload and low heat generation, ensuring stable operation of feed systems such as machining centers, CNC lathes and grinding machines. They reduce axial play, reversal error and thermal deformation, optimize the transmission supply chain for precision machine tools and ease production risks caused by unstable delivery cycles of imported screw support bearings.