Lösningsmedelssvetsning

Lösningsmedelssvetsning, also known as solvent welding or solvent cementing, is a method used to join thermoplastic materials, particularly those with a similar chemical composition. It is not a true welding process in the sense of melting and fusing the base materials with heat. Instead, it relies on the use of a solvent to temporarily soften or dissolve the surfaces of the plastic parts being joined.

The process involves applying a solvent, often a liquid or gel, to the surfaces of the two pieces of plastic that are to be joined. This solvent penetrates the plastic, causing it to swell and become pliable. Once the surfaces are sufficiently softened, they are pressed together. The solvent then evaporates, allowing the plastic to re-harden and form a bond. The effectiveness of the bond depends on the compatibility between the solvent and the plastic, as well as the diffusion of the solvent and subsequent re-solidification of the polymer chains.

Commonly joined materials include PVC, ABS, acrylic, and polystyrene. Lösningsmedelssvetsning is widely used in plumbing for joining PVC pipes, in the manufacturing of plastic models, and in various assembly operations where a strong, watertight, or airtight bond is required without the need for high temperatures or specialized equipment. Proper ventilation is important due to the volatile nature of many solvents used. The choice of solvent is critical; it must be able to dissolve the specific plastic without causing excessive degradation or making it too brittle.