THK, HIWIN and NSK are among the established manufacturers commonly associated with ball screws and ball nuts. Each company offers multiple product series for different accuracy, load, speed and installation requirements.
However, a familiar brand name does not automatically make a ball nut suitable for a particular machine. Ball nuts from different manufacturers-or even different series from the same manufacturer-may not be interchangeable. Screw diameter, lead, raceway geometry, nut dimensions, circulation structure, preload and accuracy must all be checked.
Well-Known Ball Nut and Ball Screw Brands
THK
THK is a Japanese linear motion manufacturer with an extensive ball screw product range. Its ball nuts use different ball recirculation methods, including return-pipe, deflector and end-cap structures.
The available product range includes precision and rolled ball screws, finished shaft-end assemblies, rotary-nut designs and other configurations for machine tools, automation equipment and precision positioning systems.
When replacing a THK ball nut, the complete model code should be checked. THK states that nuts for certain rolled ball screws may be supplied separately, while precision ball screws may need to be purchased as a matched screw-and-nut set.
HIWIN
HIWIN is a linear motion manufacturer based in Taiwan. Its ball screw product range is used in machine tools, industrial automation, electronics equipment and other motion-control systems.
HIWIN ball screws are available in different diameters, leads, nut shapes and accuracy classes. Standard flange nuts, double nuts, high-lead designs and other structures may be selected according to the application.
Similar model numbers do not guarantee direct replacement. Flange dimensions, mounting holes, nut length, preload and screw compatibility should be compared with the original drawing.
NSK
NSK is a Japanese manufacturer with ball screw products for machine tools, general industrial machinery, injection-molding equipment, semiconductor equipment and other specialized applications.
Its product range includes standard stocked ball screws, precision types, high-load series, high-speed designs and products with finished or unfinished shaft ends.
NSK product selection is based on the complete ball screw assembly rather than the nut name alone. Load ratings, accuracy grade, axial clearance, lubrication and mounting arrangement should be confirmed from the applicable technical data.
Why Brand Name Alone Is Not Enough
A ball nut is not a universal threaded nut. Its internal raceway must match the ball screw shaft and the balls must circulate correctly under load. Two nuts described as "1605," for example, may both be intended for a nominal 16 mm screw with a 5 mm lead, but their body dimensions, flange geometry, ball circulation system and internal matching may still differ.
Before ordering a replacement, compare the following:
- Complete manufacturer and model number
- Nominal screw shaft diameter
- Ball screw lead
- Right-hand or left-hand thread direction
- Nut body and flange dimensions
- Mounting-hole diameter and position
- Ball circulation structure
- Single-nut or double-nut construction
- Axial clearance or preload requirement
- Accuracy grade and load rating
- Lubrication-hole and seal arrangement
Can a Ball Nut from Another Brand Replace the Original?
A cross-brand replacement may be possible in some standard rolled ball screw applications, but it should never be assumed from the diameter and lead code alone.
Three different levels of compatibility must be checked:
1. Screw and Raceway Compatibility
The replacement nut must match the screw lead, thread direction, raceway profile and ball geometry. A nut that can be threaded onto the shaft is not necessarily suitable for operation under load.
2. Installation Compatibility
The nut outside diameter, flange width, bolt-hole pattern, pilot diameter and overall length must fit the existing nut housing and machine table.
3. Performance Compatibility
Dynamic load rating, static load rating, preload, axial clearance, rigidity, accuracy and allowable speed must meet the machine's operating requirements.
Important: If the existing screw is worn, damaged or its original specifications cannot be confirmed, replacing the complete screw-and-nut assembly is usually safer than installing a nut alone.
Common Ball Nut Types
Brand comparison is only one part of selection. The nut structure must also suit the machine layout and operating conditions.
- Standard flanged single nut: commonly used in CNC machines, automation equipment, 3D printers and general linear motion assemblies.
- Double ball nut: used when preload, reduced axial clearance and higher axial rigidity are required.
- Internal-circulation nut: provides a compact structure for equipment with limited installation space.
- End-cap circulation nut: often used for large-lead and high-speed linear movement.
- Rotary nut unit: integrates the nut with a bearing and drive structure for applications in which the nut rotates and the screw shaft remains fixed.
DLY Ball Screw Nut Supply
DLY manufactures and supplies ball screw nuts for replacement, machine repair, spare-parts stocking and matched ball screw assemblies. Available structures include SFU, SFA, SFE, SFY, SFNU, internal-circulation nuts and double-nut designs.
DLY ball screw shafts are commonly produced from S55C, while the ball nuts use 20CrMo. Standard rolled ball screw assemblies are available in C7, with ground C5 options available for applications requiring higher positioning accuracy.
DLY rotating ball nut assembly for fixed-screw linear motion systems
DLY waist-type SFU ball screw nut
View the DLY ball nut range to compare available nut types and replacement options.
How to Request a Replacement Ball Nut
Providing complete information is more useful than sending only a brand name. For model confirmation, prepare:
- The full code marked on the old nut or screw
- Clear photos of the nut, flange and screw shaft
- Screw diameter and lead
- Nut and flange dimensions
- Mounting-hole positions
- Machine type and installation direction
- Required quantity
- Original drawing, if available
Do not remove an installed nut from the screw shaft without a suitable transfer sleeve. The balls may fall out, and incorrect reassembly can damage the raceway or change the operating clearance.
Conclusion
THK, HIWIN and NSK are established names in the ball screw industry, but brand recognition should not replace technical verification. A suitable ball nut must match the screw shaft, mounting structure and required operating performance.
For replacement projects, begin with the original model code and dimensional drawing. When compatibility cannot be confirmed, replacing the matched ball screw and nut assembly is generally more reliable than choosing a nut according to brand, diameter or price alone.
Need help identifying a replacement ball nut?
Send DLY the old model number, screw diameter, lead, nut dimensions, photos and drawing. We can help check whether a nut-only replacement or a matched assembly is more suitable.
