Plastics welding process includes crosslinking of the polymer molecules join the pieces. A filler material is used to fuse the workpieces. However, the joints form when the part cools below the melting temperature.
Thermosets cannot be welded after the crosslinking of molecules takes place.
Types Of Plastics Welding
Hot gas welding
Hot plate welding
Plastics Welding – Type 1 – Hot Plate Welding
This is a specific kind of plastics welding process. The heat generated from the hot plate helps in fusing the parts. This hot plate lies between the joining surfaces. The workpieces become soft and hot, and the plate is removed after a specific time interval. The workpieces are fused and pressed using high strength. However, the polymer crosslinking of molecules occur after the parts cool down. Hence, a solid joint takes place.
The hot plates use aluminum alloys as the base material. This plate uses electric heating elements along with thermocouple that helps in maintaining the temperature control of the surface.
Plastics Welding – Type 2 – Hot Gas Welding
The heat generated from the hot gas stream helps in welding. It is known as hot gas welding. Electric heating elements help to heat the gas, present inside the welding gun. The welding gun appropriately directs the gas towards the surfaces of the workpieces and a filler material rod. The filler rod material and the joint parts amalgamate at the edges. The polymer crosslinking of the molecules happens after the pieces cool down. Thus, it develops a powerful bond or joint.
A high level of operator skill is necessary for this manual process. Moreover, certain types of polymers demand oxidizing at high temperatures. Hence, hot nitrogen accomplishes the task of welding.
In the ultrasonic plastics welding process, the fusion of workpieces takes place with the application of pressure and high-frequency acoustic vibration or ultrasonic. A metal tool transmits ultrasonic vibration.
It takes only one second to complete a cycle. The acoustic vibration frequency ranges between 20 – 70 kHz. The amplitude of this vibration is near about 0.05 mm. However, the thickness of the fused pieces depends on the power generated from the ultrasonic generator.
In this process, two cylindrical parts get in touch with one another via friction pressure. One of the parts keeps rotating continuously. The resulted friction leads to heat generation at the ends and rotation stops after a specific interval of time. Axial pressure helps to fuse the molten lava after cooling.
In this process, workpieces vibrate at a specific amplitude and frequency. Both the parts rub against each other under particular pressure. As a result, it leads to friction and heat generation. The resulted heat helps in melting the polymer present in the joining area.
Moreover, this kind of welding is primary use in the domestic and automatic appliance industries.
Different types of plastics welding processes are available. However, the type of procedure that fits your requirements depends on several factors. Also, the kind of material you use and the output you want are the essential facts.