Foam cutting knife for thermal insulation pipe

The utility model relates to the field of pipe cutting tools, and provides a thermal insulation pipe foam cutter which comprises a first buckling part and a second buckling part which are rotationally connected. The inner wall of the first buckling part and the inner wall of the second buckling part are matched to form a holding cavity which can contain the heat preservation pipe foam and is matched with the heat preservation pipe foam in shape, and the first buckling part and the second buckling part are matched to be used for completely holding or partially holding the heat preservation pipe foam. The inner wall of the first buckling part and/or the inner wall of the second buckling part are/is provided with a cutting piece used for cutting the thermal insulation pipe foam, and the cutting piece is provided with a tip end conveniently inserted into the thermal insulation pipe foam and a blade point used for cutting off the thermal insulation pipe foam, wherein the cutting direction of the blade point is the