Here are the three major classifications of methods that are employed when assembling plastic components:
- In cases where the materials used are not compatible and a permanent method must be used, adhesives are ideal. There are various kinds of adhesives available in the market; each can be used for different applications. For best results, consult the manufacturer of adhesives and seek out advice for the right product for a specific application. Keep in mind to know the cost of the product and if it requires any tool when dispensed. Parts applied with adhesives must also be clamp together for a time until the adhesive is dry.
- This category includes screws, press fit, snap fit and rivets. This option is widely used if the assembled product requires to be disassembled sooner or later. This is efficient for applications with low volume.
- Friction and heat. This is done on compatible materials and the effect is permanent.
- Ultrasonic assembly. This technique is widely used because it is cost-effective. The advantages of using this method is that it is done fast, setup time is minimum, there is no consumables, capital equipment used are low cost and it can be easily integrated into an automatic system. The ultrasonic assembly is composed of a converter, horn, power supple, booster and actuator. This works by sending mechanical force and vibration to the components. The part where the components mate creates heat which melts the plastic thus resulting in a strong bond.
- Vibration welding. This method is done by applying linear motion to the mating part. The motion applied is under force and must be a reciprocal. One advantage of this technique is that the cycle time is short. This process can be used an almost all thermoplastics.
- Spin welding. This is used to assemble two parts made of thermoplastics which then create a molecular bond. The component joint of the two thermoplastic must be circular in order for spin welding to work.
- Hot plate welding. One big advantage of this method is that welding can be done on any part shape. The curvature must equal the heat inserted and then the method can work. Additional advantage is that the weld created is homogeneous and very solid.
- Laser welding. This joining process is ideal because it gives clean results and the process is gentle. This is used in materials that have complex geometries or those that can’t be bonded using other methods.
- Thermal processing. This method is done by heating the tip and softens the plastic before molding it into a certain shape. If another material is to be inserted such as metal, the heated tip touches the metal instead which is used as a medium to transfer heat into the plastic, softening it before inserting the metal.