Thomas Edison. Thomas Alva Edison (February 11, 1847 â October 18, 1931) was an American inventor and businessman, who has been described as America's greatest inventor. He developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and the long-lasting, practical electric light bulb.
Pipe dope, or pipe joint compound, is a gooey compound used to seal the connection between threaded pipes and fittings. Because the threads in pipes and fittings still leave an air gap between the two surfaces, the gap must be filled to make it water tight (or gas tight for gas lines).
Perforated pipe plays an integral role in many applications of HDPE pipe. Generally, perforated pipe is used to. accelerate the removal of subsurface water in soils or to allow storm water to percolate into the soil. Currently, two. classifications of perforations are specified in the AASHTO material specifications for HDPE pipe: Class I, and Class II.