Our blowpipes don’t get hot for a number of reasons. Mostly, the pipes are only briefly exposed to heat themselves when gathering. When re-heating, the glass is heated and not the pipe. Glass is an excellent insulator, and does not conduct heat into the pipe. Today, our pipes are made of stainless steel which also helps, since stainless is a poor conductor of heat. In addition, pipes are long enough that the glassmaker can always hold the pipe safely.