Techniques for welding thermoplastic tubes

In a method of welding two thermoplastic tubes which are cut into sections with a cut end of one tube being aligned with a cut end of another tube and with the aligned cut ends being mounted in a holding device and being heated and then pressed together to become welded, the improvement comprising cutting the tubes before the tubes are mounted in the holding device, mounting the cut ends of the tubes in the holding device with the cut ends aligned, pressing the aligned cut ends against a cold wafer, heating the wafer to flatten the contacting surfaces of the cut ends, manipulating the holding device to withdraw the cut ends out of contact with the wafer, heating the wafer to radiantly melt the cut ends, withdrawing the wafer out of the path of movement of the cut ends, and pressing the melted cut ends into contact with each other to weld the cut ends together.