Plastics, of which there are many different types, are one of the most durable materials imaginable. Many of them are on par with or even better than materials such as steel, concrete and iron. In order for plastic products to retain the same durability and strength when multiple parts are combined, they must be joined together in the best possible way.
There are several techniques for plastic welding, including:
- Hot air welding
- Extruder welding
- Sleeve welding
- Electrofusion welding
- Butt welding
When welding plastics for tubs, tanks or other containers and for various industrial plastic structures, hot air or extruder welding are often used. These types of welding are also suitable for welding large pipe structures.
When welding small pipe structures, sleeve, butt or electrofusion welding are often used.
Plastic is welded using the best techniques and equipment, to ensure the best possible welds for the various plastics types and structures.
It is important to consider the plastic material being used when welding plastic, as this has an impact on the welding process.
For the production of plastic structures that have to be able to hold various liquids or other materials, such as pipes, tubs and other containers, it is recommended that plastic welding be used. Plastic welding is also recommended for the manufacture of plastic structures exposed to loads, as the weld creates an extremely strong joint.
When welding components made of thermoplastic materials, it is the thermoplastic properties of the material that make welding possible. During welding, the plastic material is heated until the thermoplastic state is reached. In the thermoplastic state, the molecules in the plastic are liquid, and can be made to join together by applying the right pressure. After cooling, the two plastic components will be welded together with a strong bond, and can be used for the given application.
Gluing plastic is a more complex task in terms of creating a clean and durable bond. This is because it is difficult to achieve a smooth glue joint for most plastics, especially for small gluing surfaces. So it is harder to achieve the same strength and durability that welding offers. It is not impossible to glue several types of plastics, but some plastics are more suited to gluing than others. It also depends very much on what the structure is to be used for.
The plastic types most suitable for gluing are PMMA (acrylic) and PC (polycarbonate). PMMA can be glued in such a way that the joints and thus the resulting structure are essentially as strong as the plastic itself. Thorough preparation is required when gluing plastic structures, because the plastic surfaces to be glued must be completely clean and free off dirt, grease and the like, to ensure the best adhesion.
Plastic gluing is often done using glue products containing a solvent that acts on the plastic. The plastic parts are then pressed together, so that they become joined in a single structure once the glue has hardened.