How to Weld Plastic

Welding is not something that is only dedicated to welding heavy metal joining such as stainless steel or aluminum. Therefore if you are working on such a project working with core knowledge is important.

Plastic welding is a popular process that is used to soften the thermoplastic using heat to make a strong weld. However there is a proper way to do that and if you are a newbie welder, we shall take a deep note on how to weld plastic

How to Weld Plastic Step-By-Step

Plastic is welded using the heat that is directed by a welder. However, the application of the heat depends on what type of plastic is being used. To know its step-by-step process here is what you need to do!

Clean the plastic and setup place

Whichever malarial you weld, cleaning it thoroughly before you start welding is not only important to prevent damage but also helps in the strong weld.

For plastic welding, you can use a liquid solvent to clean the plastic for stains, and oiliness from the surface. In setting up the workspace, you should wear a protective kit and make sure you know the plastic-type such as Polypropylene, Polyvinyl Chloride, and Polyethylene.

Attach the plastic

For joining the plastic, preheating is a must to make the material soft enough. Preheating for 2- 3minutes would be enough but each plastic type has its heating or melting point. Therefore, always set the welder temperature as per the material that you intend to weld.

Mostly the suggested temperature ranges are ranges from 200°C to 300 °C or 390°F to 570°F. Tack-weld the plastic end for security and you can also use a plier to trim down the end of the plastic after tack-welding.

Let the Plastic Cool

After preheating and tack-welding, wait for about 5 minutes to cool down the plastic at room temperature. For smoother consistency and leveled joints use the 12-grit sandpaper. Now the ready drill starts, welding the plastic.

Other Ways of Welding

Welding the plastic, there are many ways. And some of the common and easy ways are as follows

Ultrasonic Welding: in this welding process the heat is used for joining the thermoplastic that is directed from a high-frequency acoustic vibration which is done by the conversion of high-frequency electrical energy into high-frequency mechanical motion.

Radio Frequency Welding: This type of welding for plastic features high-frequency electrical energy or radio waves and it takes only 2-5 seconds to complete the process.

Hot Air Welding: Hot air welding for plastic is also known as gas welding. The gas is directed when the air is in the electrically heated welder gun.

Laser Welding: In laser weld, the laser beam is pressed for the joining line to solidify the plastic. It takes about 3 to 5 seconds. In this welding process, two parts of the weld are compressed to each other.

Vibration Welding: In vibration welding, friction is used to initiate heat to weld the plastic. The parts that you need to weld are then rubbed against each other and then the uninterrupted vibrating produces heat. This heat melts down the thermoplastic to make the welded fuse and this whole process takes only 1-5 seconds.



So that was it about how to weld the plastic. We hope you have fully understood the process and if you still have any doubt, it is better to take the help from an expert welder and practice the steps on a test workpiece before you actually start welding on a professional piece.


About Samantha Joel

Meet Samantha, a Certified Welding Educator (CWE) and Certified Resistance Welding Technician (CRWT) from the American Welding Institute. She loves Welding Stuff, and apart from being a professional in welding jobs, it's her hobby too. She's working part-time blogger and reviews welding equipment here.