blästrad

Blästrad is a term used in Swedish to describe a surface that has undergone abrasive blasting, commonly referred to in English as sandblasting. The process propels an abrasive medium at high velocity onto a surface, with the aim of cleaning, removing contaminants, creating a uniform texture, or etching the material for improved adhesion of coatings or subsequent processing.

Blästring can be performed with various media and methods. Dry blasting uses dry abrasive particles, while wet blasting incorporates liquids to reduce dust. Common media include sand (historical), glass beads, garnet, aluminum oxide, slag, steel grit or shot, and ceramic particulates. The choice of media, pressure, stand-off distance, and blasting time determines the surface roughness and whether the goal is cleaning, etching, or texturing. The resulting texture is typically described by roughness measurements (Ra) and the type of finish (matte, satin, or excavated).

Typical applications include preparing metal parts and structures for painting or coatings, cleaning and restoring castings, architectural or decorative metalwork, concrete surfaces, and glass or stone elements. Blästrad surfaces improve coating adhesion, remove rust, scale, or old coatings, and can create a consistent, non-reflective appearance.

Safety and standards are important considerations. Blasting generates dust and noise and may pose hazards from silica dust or embedded particles, so appropriate containment, ventilation, enclosures, and personal protective equipment are required. Standards and guidelines (such as ISO surface-preparation standards or region-specific SSPC/ISO norms) help define acceptable cleanliness, roughness, and surface condition after blasting.