In CNC machine tools, precision measurement equipment, automation drive modules and semiconductor manufacturing systems, the positioning accuracy of ball screws directly determines machining quality and product yield. The screw support bearings are the critical line of defense in maintaining this precision. When bearing axial clearance is excessive, the screw loses travel during reverse operation, causing positioning accuracy to drift; when bearing rigidity is insufficient, cutting forces or load variations cause axial displacement of the screw, leaving waviness or steps on machined surfaces. Many equipment manufacturers face this dilemma: static precision tests pass all specifications, yet dimensional deviations emerge once cutting loads are applied—the problem is often not with the screw itself, but with the rigidity and preload condition of the support bearings.

 

Japan NMT screw support bearings are specialized products engineered specifically to meet the demanding requirements of high-precision screw drives for bearing axial rigidity and positioning accuracy. NMT screw support bearings typically employ angular contact ball bearings or paired tapered roller bearing structures, operating with precisely set preload to achieve zero or slight negative clearance operation—fundamentally eliminating the possibility of axial displacement.

 

NMT enforces exceptionally stringent manufacturing standards for preload control in screw support bearings. The protrusion deviation of paired bearings is controlled within an extremely narrow range, ensuring preload after installation closely matches design values. Bearing contact angles are precisely calculated and validated—standard 60° contact angles maximize axial rigidity, while optimized smaller contact angles for high-speed applications reduce heat generation. Raceway curvature radius and ball diameter matching are repeatedly optimized to achieve optimal balance between load capacity and low friction. Raceway surfaces undergo superfinishing to achieve exceptionally high surface finish, maintaining low friction and temperature rise even at high speeds.

 

In screw drives, bearings often must withstand bidirectional axial loads—cutting forces in forward direction and tool retraction forces in reverse direction are completely opposite. NMT screw support bearings are mounted in paired configurations that provide equal axial rigidity in both directions, ensuring consistent positioning accuracy regardless of movement direction. Bearing cages are specifically designed for high-frequency reciprocating motion in screw supports, utilizing high-strength engineering plastic or phenolic resin materials that combine lightweight construction with adequate guidance precision—maintaining stable rolling element arrangement under frequent reversing conditions.

 

Reasons for selecting NMT screw support bearings:

 

High axial rigidity design fundamentally eliminates screw axial displacement

 

Precision-controlled paired bearing protrusion ensures preload matches design values

 

Standard 60° contact angle maximizes axial rigidity

 

Optimized contact angle options for high-speed applications balance speed and rigidity

 

Superfinished raceways deliver extremely low friction and controlled temperature rise

 

Equal-rigidity paired mounting ensures consistent positioning accuracy in both directions

 

Specialized cage materials and structures for high-frequency reversing applications

 

Precision grades up to P4 and P2 for ultra-precision positioning requirements

 

These performance advantages establish NMT screw support bearings as the core positioning components for CNC machine tools, precision measurement equipment, automation drive modules, semiconductor manufacturing systems and various high-precision screw drive applications.

 

Application scenarios

 

CNC lathes, milling machines and machining center screw supports, precision grinders and coordinate measuring machines, laser cutting and engraving equipment screw drives, automation slides and linear module screw drives, semiconductor wafer dicing saws and die bonders, 3D printing and additive manufacturing Z-axis screws, precision presses and stamping equipment, medical imaging equipment precision positioning mechanisms.

 

Precision manufacturing

 

Produced according to Japanese industrial standards and screw bearing manufacturing specifications, NMT screw support bearings utilize high-purity bearing steel processed through precision forging, raceway superfinishing, contact angle precision control, paired bearing protrusion precision matching, preload precision setting, high-speed dynamic balance inspection, rotational accuracy verification, temperature rise testing and durability fatigue validation—ensuring every product delivers reliable rigidity, precise positioning and stable operation.

 

Product range

 

60° contact angle screw support bearings, high-speed screw support bearings, ultra-precision grade (P4/P2) screw support bearings, paired combination screw support bearings, sealed screw support bearings, stainless steel screw support bearings and custom non-standard screw support bearings.

 

Global industrial service

 

Japan NMT supplies high-quality screw support bearings to global CNC machine tool manufacturers, precision equipment builders and automation system providers, empowering global precision screw drive requirements with high axial rigidity and precision positioning craftsmanship.