Abstract: An improved method and apparatus for shielding inert gas from seeping out of metal pipes in a welding application wherein a high-temperature resistant purge strap is placed around the weld gap and the pipe ends. Advantageously, the purge strap is equipped with a window to allow the welder access to the pipe ends. Dams may be inserted into each pipe near the end to be welded, the purge strap placed about the pipes covering the end of each, and inert gas pumped into the pipes, displacing the air within the pipes. A weld bead is laid into the gap and the purge strap is shifted around the circumference of the pipes to allow completion of the weld. The purge strap device is also disclosed.