China Precision Lock Nuts Manufacturers Suppliers Factory - Made in China

Precision Lock Nuts for Ball Screw and Spindle Assemblies

Maintain exact bearing preload and axial alignment with thread tolerances controlled within ISO 4H and runout below 0.002 mm.

Double Lock Nuts
Double Lock Nuts integrate two radial copper locking pins set at a specific pitch angle to maintain constant thread engagement on dynamic shafts. Designed with precision-ground axial working faces
Preload Lock Nuts
Preload Lock Nuts deliver precise axial positioning and runout control for precision shafts, angular contact bearings, and ball screw drive units. Built with integrated brass locking pins and
K-Type Lock Nuts
K-Type Lock Nuts utilize three radial locking pins positioned at 90-degree intervals to secure machine shaft threads without creating axial deflection. This radial tension design maintains
F-Type Lock Nuts
F-Type Precision Lock Nuts incorporate three radially arranged brass pins angled at 30° to grip shaft threads. This locking geometry secures components without deforming thread flanks or compromising
RN-Type Lock Nuts
RN-Type Lock Nuts maintain precise axial positioning and preloading on drive shafts, ball screws, and spindle bearings. Utilizing three radial brass-tipped locking pins spaced at 120-degree
R-Type Lock Nuts
R-Type Lock Nuts provide high-accuracy axial positioning for bearings and dynamic shaft components. Built with three radial brass locking shoes, these units clamp securely onto male threads without

Category Overview

Precision Lock Nuts secure bearings along threaded shafts without relying on secondary lock washers, keyways, or locking plates. By integrating internal brass locking pins or elastic deformation threads, these components eliminate axial play, maintain constant clamping force under dynamic reverse loads, and prevent runout-induced spindle failure.

Product Structures and Locking Types

RN Series (Radial Locking)

Three brass locking pins positioned radially at 120-degree intervals. Tightening the setscrews forces the pins against the shaft thread without distorting the nut face. Ideal for compact radial clearance.

F Series (Axial Locking)

Locking screws positioned parallel to the shaft axis. Clamping force applies directly along the thread flank, providing maximum resistance to axial force in heavy-cutting spindle applications.

A Series (Angle Locking)

Pins set at an angle matching the thread flank. Contact occurs directly on the thread angle, distributing pressure evenly across the thread profile for high-speed rotation.

M Series (Self-Locking / Elastic Deformation)

Slotted nut body utilizes micro-deformation created by axial locking screws. No brass pins required; best suited for extreme temperature environments where polymer or soft-metal inserts might degrade.

Technical Specifications

Model Series	Thread Pitch Range	Out-of-Squareness (Runout)	Material Options	Surface Treatment	Thread Tolerance
RN Series (Radial)	M6x0.75 to M200x3.0	0.002 mm - 0.005 mm	42CrMo / S45C	Black Oxide / Nickel Plated	ISO 4H
F Series (Axial)	M10x1.0 to M150x2.0	0.002 mm - 0.003 mm	42CrMo / S45C	Black Oxide / Phosphate	ISO 4H
A Series (Angle)	M12x1.0 to M100x2.0	0.002 mm	42CrMo	Black Oxide	ISO 4H
M Series (Slotted)	M8x0.75 to M80x1.5	0.005 mm	40Cr / Stainless Steel	Natural / Black Oxide	ISO 6H / 4H

Key Technical Advantages

Grinding Precision
Thread flanks and perpendicular mating faces are precision-ground in a single clamping setup to guarantee perpendicularity under 0.002 mm.

Locking Pin Alignment
Brass inserts are machined to match the exact pitch angle of the internal thread, preventing localized thread deformation on the shaft.

Dynamic Balance
Symmetrical mass distribution supports rotation speeds up to 20,000 RPM without generating secondary vibration.

Hardness Profile
Heat-treated to HRC 28-32 on the body to absorb high tightening torques without thread stripping.

Application Areas

Machine Tool Spindles

Fixes angular contact ball bearings in place, maintaining rigidity during continuous high-speed milling.

Ball Screw Support Units

Secures fixed-end bearing blocks to eliminate axial backlash in precision motion axes.

Robotics and Servo Drives

Prevents nut backing-off during rapid start-stop cycles and high-frequency reversals.

Medical Positioning Stages

Provides clean, repeatable axial clamping without generating wear debris inside sterile drive units.

Selection Guide

Determine Space Constraints

Choose RN Series if radial access is unobstructed; select F Series if access is only available from the front face.

Calculate Axial Load Requirements

Select F Series or A Series for heavy machining axes; use RN Series for standard automation drives.

Verify Shaft Thread Spec

Match the internal nut thread to the shaft thread class (ISO 4H standard).

Select Surface Finish

Standard black oxide for lubricated environments; nickel plating or stainless steel for cleanroom or corrosive conditions.

Customization and OEM Production

Custom Pitch and Thread Profiles
Fine threads, trapezoidal profiles, left-hand threads, and custom diameters up to M300.

Alternative Materials
Stainless steel (SUS304/SUS316) for food processing; alloy steels hardened up to HRC 45 for extreme shock loads.

Modified Geometry
Custom face spanner slots, side wrench holes, keyways, or integrated encoder target rings.

Specialized Coatings
Electroless nickel, manganese phosphate, or zinc-nickel plating for enhanced corrosion resistance.

Why Choose Us

01/

100% Thread Gauging
Every unit passes full-length Go/No-Go thread plug gauge testing prior to final inspection.

02/

Sub-Micron Measurement
Optical comparators and air gauges measure face runout and pitch error on every batch.

03/

Material Traceability
Raw material heat numbers and mill certificates recorded for full lot tracking.

04/

In-House Heat Treatment
Controlled atmosphere induction hardening eliminates internal stress and dimensional drifting over time.

FAQ

Q: What runout tolerance can be expected on standard production runs?

A: Standard production maintains face perpendicularity to thread pitch line within 0.002 mm to 0.005 mm depending on thread diameter.

Q: How are locking pins prevented from damaging shaft threads?

A: Locking pins are made from soft brass or copper with contact faces pre-machined to match the internal thread profile, distributing clamping force evenly across the thread flanks.

Q: Can precision lock nuts be reused after disassembly?

A: Yes. Because the locking pins deform against the shaft thread without galling the metal, the nut can be loosened and retightened multiple times without loss of locking torque.

Q: What torque should be applied to the set screws?

A: Recommended tightening torques for set screws vary by thread size and are detailed in the technical datasheet accompanying each series batch.

Q: Are custom left-hand threads available for high-speed reversing shafts?

A: Left-hand threads are manufactured to order across all series sizes with identical lead times to standard options.

Request Technical Datasheets and Pricing

Submit your shaft specifications or CAD files to receive dimensional drawings, torque calculations, and volume pricing within 24 hours.

Request Technical Quote

As one of the leading precision lock nuts manufacturers and suppliers in China, we warmly welcome you to wholesale customized precision lock nuts made in China here from our factory. For quotation, contact us now.