Ice as a Bending Medium for Wave-Guide and Tubing (Correspondence)

Bending waveguide and metal tubing is very often a difficult and time-consuming task. Low melting temperature alloys are at times difficult to remove from waveguide and tubing. The piece to be bent may be filled with water which is then frozen by dry ice, liquid nitrogen, or by a deep freeze. In some applications where the piece to be bent is integral with a larger system, a block of dry ice may be held against it to freeze only the portion of water around the section to be bent. The use of these low temperatures causes not only the water to freeze into quite small crystals (which act like a sand packing), but also prevents the ice from melting because of the pressure of bending.