Round caps for bolts and threads

Round caps for bolts and threads protect delicate threaded surfaces from damage, corrosion and dirt, from production and storage through to final assembly.

Corrosion protection
Secure fit on threads
Colour coding
Easy tool-free fitting
Vinylflex.cz Pozadí

Protecting pipe and flange threads

The round cap fits easily over the part and helps prevent damage during production, storage and transport.

Applications — protecting pipe and flange threads

Caps fit over threaded ends of pipes, flanges, pins and bolts to protect threads from mechanical damage and dirt that could make assembly difficult.

Why protect bolts and threads

A damaged or corroded thread can render an entire part unusable. A cap prevents moisture-related corrosion, protects against scratches during handling and transport, and covers sharp thread edges for safer handling.

Size range and selection

We make caps with an internal diameter of 2–110 mm and production tolerances of ±0.3 mm for wall thickness and ±1 mm for length. Choose according to the outside diameter of the thread and the length to be protected.

Colour coding for easy identification

Eight colour options — black, white, yellow, blue, green, red, grey and orange — let you distinguish thread types and sizes quickly in storage or on the production line.

Custom manufacturing for non-standard sizes

For unusual threads, whether metric or specialised, we can make a cap from your sample or drawing, including a dedicated tool.

Typical uses

Bolts and pins — protecting heads and shanks against damage and corrosion Pipe threads — keeping dirt out of external and internal threads Flanges — protecting threaded flange holes during storage and assembly Storage — long-term protection of fasteners in stock Surface finishing — masking threads during painting, galvanising or plastic coating Assembly lines — colour coding bolt and thread types during production

What to prepare before choosing

  • Outside diameter of the part
  • Required cap length
  • Quantity and order frequency
  • Colour

Examples and technical details

Fotografie - Válcové krytky
Fotografie: řezání krytek na míru - různé krytky

What to know before choosing a round cap

No. Flexible PVC is gentle even on fine threads and leaves no marks or scratches on the metal surface.
Yes. We offer eight colours commonly used to distinguish thread sizes or types at a glance.
Yes. It keeps paint or plastic coating out of the thread and is easy to remove afterwards.
Yes. We make custom sizes from a drawing or sample and can manufacture the required tool in-house.
Yes. As the manufacturer, we provide high-volume and repeat deliveries for distributors and production facilities.

STANDARD SIZES

Know the size? Choose a standard cap in our online shop.

If you are unsure, request a sample or send us a drawing.

Visit the online shop Or request a custom solution →