| Standard | DIN 1587, DIN934, DIN917 |
| Grade | 4.8, 8.8, 10.9 |
| Surface Treatment | ZP, YZP, PL |
Product Introduction
Standard Name: Cap Nut or Acorn Nut (Cover Nut / Cap Nut).
Common Names: Cap Nut, Hex Cap Nut, Acorn Nut.
Product Definition: A hex nut with a closed top featuring a smooth dome or conical shape. Its core function is to cover and protect exposed thread ends while completing threaded fastening, thereby achieving dustproofing, scratch prevention, enhanced safety, and improved aesthetic appeal.
Cap Nut Key Features
Dome-shaped design: The smooth, dome-shaped top completely covers the bolt end, providing an
aesthetically pleasing appearance, protecting the threads, and preventing accidental damage.
Hexagonal drive: The hexagonal shape facilitates wrench tightening, ensuring efficient installation.
Materials and coatings: Commonly made of carbon steel, stainless steel, brass, or alloy steel, with zinc
plating (ZP), chrome plating, or blackening finishes, providing corrosion resistance and a decorative effect.
Various sizes: Diameters M4-M36, moderate height, conforming to standards such as DIN 1587 and ISO 917.
Advantages: Aesthetically pleasing, thread-protected, easy to install, suitable for exposed applications,
but with moderate strength and not suitable for high loads.
Working Principle
Threaded fit: The internal thread matches the external thread of the bolt, generating axial clamping
force through rotation.
Sealed fixation: The dome covers the bolt end, preventing dust ingress and protecting the threads;
the hexagonal shape facilitates torque application.
Load Distribution: Evenly distributes tensile force; the coating provides corrosion protection; the
principle involves friction and mechanical interlocking.
Installation Control: The dome ensures a neat finish when tightened, preventing overtightening and
damage to the appearance.
Product Applications
Furniture and Decor: Secures bed frames, lamps, or railings, providing a smooth finish to prevent
scratches.
Automotive and Motorcycle: Assembles wheels, hoods, or trim pieces; chrome-plated versions enhance
aesthetics.
Machinery: Protects exposed bolt ends, such as on machine tools or pumps and valves.
Construction and Outdoor: Used for fences, playground equipment, or piping; stainless steel versions
offer corrosion resistance.
DIY and Home Furnishings: Economical and aesthetically pleasing finishing accessories for routine
maintenance or projects.
