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In hot gas welding of thermoplastics, what is the difference between 'speed welding' and 'hand welding'?


Frequently Asked Questions

Speed welding of thermoplastics involves the use of a hot air welding torch supplying a smooth flow of hot gas to the joint prep and a filler rod of the same material as the plastic to be welded. The temperature of the hot gas is specific to the material to be welded. The filler rod is fed into the joint via a specially designed nozzle with the toe of the nozzle applying a constant pressure to fuse the rod to the pre-heated parent material with a constant travel speed and torch angle.

Hand welding sometimes known as slow hand or pendulum welding, is where the filler rod is introduced into the joint by hand rather than through a nozzle, with the pressure being applied directly with the hand. The welding torch with a straight nozzle attached, is moved in a pendulum motion up the weld rod and down a small area of the weld prep with the filler rod being pushed into the pre-heated thermoplastic joint. The speed of travel combined with the pressure on the filler rod will produce a weld.

Further information

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