Plastic tubes (T1, T2) are welded by first placing the plastic tubes (T1, T2) across aligned tube slots in a pair of side by side tube holders (12, 14). The tubes (T1, T2) are clamped to create a fluid free area (40). The clamps (16, 18) in one of the tube holders (12 or 14) are shifted laterally away from the other tube holders (12 or 14) to increase the fluid free area (40) of each tube. A cold cutting device (60) cuts through the clamped tubes to create four stub ends. The four stub ends are heated/melted. The stub ends are realigned so that the one stub end in one holder (12 or 14) is aligned with the other stub end of the other tube holder (12 or 14) and the realigned stub ends are pressed into contact with each other to create a weld seam.
