Sandstrahlen

Sandstrahlen, or sandblasting, is a surface-treatment process in which abrasive particles are accelerated toward a surface to clean, roughen, or etch it. The method is used to remove rust, old paint, oxidation, and other contaminants, and to prepare surfaces for coatings or to create a textured finish. The abrasive is propelled by compressed air, a turbine, or water, and the technique can be applied in dry form or as wet blasting.

Media options vary: silica sand was historically common but is now restricted in many regions due to health risks from respirable crystalline silica. Safer alternatives include garnet, aluminum oxide, steel grit, glass beads, and slag. The choice depends on the material, desired finish, and risk considerations.

Equipment ranges from portable blast pots to large blasting cabinets. A typical setup includes a blast pot or cabinet, a nozzle, an air supply, and a containment system. The media type, nozzle size, and operating pressure dictate the aggressiveness and finish. Dry blasting generates dust; wet blasting combines liquid to suppress dust and can reduce heat generation.

Applications include cleaning and surface preparation of metal parts, ships, architectural elements, and concrete; roughening a surface to improve coating adhesion or creating decorative textures. Limitations include potential surface damage to heat-sensitive or brittle materials and the generation of waste containing removed coatings and media.

Safety and environmental controls are essential: protective clothing, eye and respiratory protection, proper ventilation or enclosed cabinets, and responsible disposal or recycling of blasting media.