Commonly Plastic Welding Techniques Used Now
Plastic welding is actually welding for the semi-finished plastic materials and is also described as a process to unite softened material surfaces with the use of heat, except for solvent welding. The welding of thermoplastics is also accomplished in 3 phases which include 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 the mechanism of heat generation at welding interface, welding methods for thermoplastics may be deemed as internal and external heating methods. In reality, there are countless of welding techniques that are being used for semi-plastic products which include the following:
Hot gas welding – this is also called as hot air welding which is a kind of plastic welding technique that is using heat. It utilizes a special heat gun that is called as hot air welder that is producing jet of hot air which softens both end parts to 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.
Air bubbles or voids in the rod will come up if the plastic welding rod has high porosity. The welding quality greatly diminished if this happens. 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 with the use of constantly heated sealing bar or die in order to apply h eat to a specific path or contact area to either seal or weld the thermoplastic together.
As a matter of fact, there are a number of applications that can be used for heat sealing like thermally activated adhesives and film, heat seal connectors or foil sealing. 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.