Calendering hole Packing, also known as Cannon Packing, as early as 1949 in the United Kingdom, is made of many thin stainless steel metal sheet with holes rolled, but the punching does not remove the metal, and make it protrude, become a rough surface, which is beneficial to the wetting of liquid on the Packing surface. It is not like filler wire mesh type coil must be repeatedly before distillation flooding make its wetting, is a kind of efficient packing used in laboratory, mechanical strength is larger, the theoretical plate number is higher, especially suitable for the test in the laboratory column experiment, and mixed loading of large industrial tower packing, so it is of high mass transfer performance, belonging to one of the efficient tower packing.