摘要 |
Apparatus for welding plastic workpieces together includes a heater block having first and second surfaces; a first heating element for radiating heat from the first surface; and a second heating element for radiating heat from the second surface; wherein the first and second heating elements being separately controlled for temperature. Temperature sensors are provided for detecting temperature of the workpieces at the weld sites. The heating elements preferably are laid out in a non-planar manner such as a parabolic, convex or other curved or angled configuration so as to focus, direct or otherwise concentrate the radiated heat toward the weld site on the workpiece. The invention is particularly suited for welding a part made of a melt processable material such as PFA to a part made of a non-melt processable material such as modified PTFE. |