The joining methods of resins are generally screw, bolt & nut, adhesive, and so on. However, from the viewpoint of the environmental issues, the method of screw and bolt & nut are taking too much time and energy to scrap and to separate resin(s) from plastics product.
Using adhesives brings about the problem of VOC (Volatile Organic Compounds). If the adhesive is dried, gas (the vaporized chemical material) will be generated. Moreover, if the adhesive is burned, the problem of toxic gas might occur.
Except for screw, bolt & nut, and adhesive, what are the joining methods of resins? They are the methods of thermal welding that are applied properties (Heating › Melting/Cooling ›H Hardening) of thermo plastics.
In a ward, it is likened to the phenomenon that 2 pieces of "Chocolate" changes to 1 piece of "Chocolate". First of all, the part that you would like to bond 2 pieces of "Chocolate" is dissolved with heating. Next, a hand overlaps each part. Finally, the part is waiting until the cooling is finished.
Also, you will be able to understand that the "Chocolate" melted by heating is carried out a function as an adhesive and is easy on the global environment.
By the way, the joining methods of resins are mainly the method of "Hot Plate Welding", "Vibration Welding", and "Ultrasonic Welding".
| HOT PLATE WELDING | |
| Principle |
First, each surface that
you would like to join 2 pieces of the thermo plastic(s) is directly
contacted with the heated hot plate in order to melt the plastic(s). Next, a hand overlaps the melted surfaces as soon as possible. Finally, the surface is waited until the cooling is finished. |
| Advantage |
Conformity materials (Most
of the thermo plastics can be used). Flexible design of welding shape (Shapes of the product and the welded section). |
| Disadvantage |
Surface appearance (Flash) Productivity (Cycle time) |
| Application | Tank, Pallet, Fan, Light |
| VIBRATION WELDING | |
| Principle |
First, each surface that
you would like to join 2 pieces of the thermo plastic(s) is vibrated on
the condition of the pressure and reciprocating motion. Finally, the frictional heat makes the plastic(s) melted and joined. |
| Advantage |
Productivity (Possible to
weld two or more parts). Reliability (Welding strength, Hermetic property). |
| Disadvantage |
Surface appearance. Vibration (E.g.: Adverse impact on the precision junction part(s). |
| Application | Tank, Fan |
| ULTRASONIC WELDING | |
| Principle |
First, each surface that
you would like to join 2 pieces of the thermo plastic(s) is vibrated on
the condition of the pressure and ultrasonic energy. Finally, the frictional heat makes the plastic(s) melted and joined. |
| Advantage |
Productivity (Welded
strength, Insert) Reliability (Welded strength, Hermetic property) |
| Disadvantage |
Surface appearance Vibration (E.g.: Adverse impact on the precision junction parts). Flexible design of welding shape (Shapes of the product and the welded section) Noise generated by the ultrasonic sound |
| Application | Lighter, Switch, Stationary, Toys, Automobile Parts, Electric Parts, Food Packaging |