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 many different welding methods that are introduced and developed to join semi finished plastic materials. Welding methods for thermoplastics are actually considered as internal and external heating methods because it depends on the generated heat mechanism at the welding interface. There are now many welding techniques used for semi-plastic products whether you believe it or not and these include:
Hot gas welding – this is also called as hot air welding which is a kind of plastic welding technique that is using heat. 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.
Hot gas/air welding is very popular fabrication technique to manufacture smaller items similar to water tanks, chemical tanks, plumbing fittings and heat exchangers.
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. There are different colors for welding rods too so it can match the material’s base color.
High porosity in plastic welding rod will lead to air bubbles or also known as voids in the rod. This should be averted as it decreases the welding quality. For this reason, it is highly recommended to use plastic welding rods that have zero porosity or known to be voidless.
Heat sealing – for this process, it seals one thermoplastic to the other such as thermoplastic using 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.
There are various applications for heat sealing whether you believe it or not similar to foil sealing, heat seal connectors, thermally activated adhesives and film. 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 using thermal adhesives is to hold clear display screens to the consumer electronic products and also, for other sealed thermo plastic devices or assemblies where ultrasonic or heat staking welding isn’t an option because of part design requirements or any other assembly consideration.