Types of Plastic Welding Techniques Used Today
Actually, plastic welding is welding semi-finished plastic materials and described as the process of uniting softened material surfaces by using heat, except for solvent welding. Welding thermoplastics can be accomplished in 3 different stages and these are surface preparation, application of pressure and heat and lastly, cooling.
There are various welding methods that have been introduced and developed for joining semi finished plastic materials. Depending on mechanism of heat generation at welding interface, the welding methods for the thermoplastics could be considered as internal and external heating methods. There are now many welding techniques used for semi-plastic products whether you believe it or not and these include:
Hot gas welding – this welding technique is making use of heat which is why it is also called as hot air welding. This is making use of a special heat gun that’s called as hot air welder that produces a jet of hot air; this as a result softens the end parts that should be joined and plastic filler rod.
In fabricating and manufacturing smaller items such as plumbing fittings, heat exchangers, chemical tanks and water tanks, hot air/gas welding is used.
Welding rod – plastic welding rod is also called as thermoplastic welding rod which is a rod with a triangular or circular cross section that is used for binding 2 pieces of plastic together. They are available in different colors to be able to match the base color of material.
Air bubbles or voids in the rod will come up if the plastic welding rod has high porosity. At all cost, this should be avoided as it is decreasing the welding quality. Having said that, the best quality of plastic welding rods are the ones that have zero porosity or called as voidless.
Heat sealing – in this process, it is sealing one thermoplastic to another similar to thermoplastic with the use of pressure and heat. Direct contact method for heat sealing using constantly heated sealing bar or die to apply heat to specific path or contact area to weld or seal the thermoplastics together.
Believe it or not, there are many different functions for heat sealing such as thermally activated adhesives as well as film, foil sealing or heat seal connectors. Joining the PCBs to LCDs in countless of consumer electronics is the most popular application for the process of heat sealing but it can be used as well in telecommunications and medical devices. Heat sealing of products is using thermal adhesives to be able to hold clear display screens to consumer electronic products, for other sealed thermo plastic devices or assemblies in which ultrasonic or heat staking welding is not a viable option as a result of part design requirements or other assembly consideration.