Silicone caps protect welded studs, whether threaded or unthreaded, during painting, powder-coating and curing processes, preventing paint from obstructing threads or other critical areas.
Silicone protective caps for short-cycle welding are fitted over studs after welding to protect external threads, internal threads and connectors during painting or powder coating.
They withstand continuous temperatures of up to 210 °C and short peaks of up to 300 °C, can be reused for hundreds of cycles, and are made to order according to the stud dimensions. Three main types are available: caps for threaded or unthreaded studs (external protection), caps for internally threaded studs (internal protection), and caps for Faston connectors (earth terminals).
1. What are silicone protective caps for short-cycle welding?
Silicone caps are temporary, reusable protectors fitted over short-cycle welded studs (types PS, IS or US) before surface-finishing processes such as wet painting, powder coating (electrostatic painting), or baking and curing.
Their main purpose is to prevent paint, powder or residue from obstructing or damaging critical mechanical areas, including external threads, internally threaded holes and Faston-type electrical connectors.
After the finishing process, the caps are removed and can be reused many times, making them an economical and sustainable accessory.
2. Technical properties of the material
| Property | Value / specification |
|---|---|
| Material | High-quality vulcanised silicone |
| Maximum continuous temperature | ≤ 210 °C |
| Peak temperature (short duration) | ≤ 300 °C |
| Reusable | Yes (hundreds of cycles) |
| Chemical resistance | Good resistance to paints, solvents and oils |
| Elasticity | High (adapts to different tolerances) |
3. Types of silicone cap
3.1. Cap for threaded studs (type PS) and unthreaded studs (type US)
Shape: Closed cylindrical cap with thin but durable walls.
Function: Completely covers the external thread or the shank of an unthreaded stud.
Typical use: Protecting studs that will remain exposed or receive nuts after painting.
3.2. Cap for internally threaded studs (type IS)
Shape: Small solid plug inserted into the threaded hole.
Function: Seals the hole and prevents paint from entering the internal thread.
Typical use: Hollow studs or threaded female fasteners that will subsequently receive another component.
3.3. Cap for earth terminals (single and double Faston)
Shape: A hood that encloses a female Faston connector (6.3 mm) or double connector.
Function: Protects the internal metal tabs and prevents paint from electrically insulating the connector.
Typical use: Earth connections on vehicle bodies, domestic appliances and electrical cabinets.