Only for professionals

B 53050 

FINE U-NUT® self-locking nuts
Material: Steel 5 | Surface: bright


Read on Hide
Böllhoff standard 53050 | material nuts: steel SS400 | bright | material insert: stainless steel | Cr (VI) - free | metric thread

FINE U-NUT® self-locking nuts are versatile and can be used as reliable shaft locknuts or locknuts for fastenings. Their strength is comparable to class 08.They have an integrated special spring made of stainless steel A2 in the form of a friction ring. This achieves a blocking effect and prevents the connection from being released automatically. The locknuts are stable in high speed rotation, vibration or changing direction of rotation. They also help to improve the rotation balance. No toothed, fan-shaped or spring elements are required, nor is it necessary to fit keyways. They are suitable for hollow axles, reusable and temperature-resistant in comparison to polyamide locknuts.

• Prevents loosening of the bearings on shafts
• Particularly suitable for high-speed rotation, vibration or changing direction of rotation
• Reusable

technical details

Read on Hide
Application Joining by bolt, joining by stud
Cr(VI) Note Cr(VI)-free
Flange/washer without flange
Installation method Screw into place with tool
Material Steel
Material version SS400
Risk hydrogen embrittlement
RoHs conformal
Surface bright
Thread type Metric fine thread


You can download CAD-files from our catalog on partcommunity: To Böllhoff partcommunity
Title Language Version File Download
Böllhoff bulletin: Changeover to Cr6+-free protective zinc layers for fasteners English 1622/15.02 894.98 KB / PDF
Data sheet: Technical information and dimensions of the product English 04/2021 122.05 KB / PDF
Fastening and assembly technology: Products and services English 1180/21-V1-EN (WBH) 8.79 MB / PDF

General questions:
Phone: +48 71 387 85 31

You come from another country? Here you can find further contact persons.