Patent ID: 7097803

Claim:
A process of making a corrugated tubular net material, comprising the steps of: preparing a tubular net material with an adequate length; heating and softening the tubular net material by a heating element; thereafter, passing the soften tubular net material without any internal support element therein through two press rollers, the press rollers spaced apart a fixed distance to permit entry of the tubular net material and rotated in relative direction so that the softened net material is flattened from a height greater than that of the fixed distance by the two press rollers to that within the fixed distance; thereafter, passing said flattened tubular net material into a separate vessel so that the flattened tubular net material is squeezed in the vessel by itself to form a plurality of bends; and releasing the bent tubular net material from the vessel such that the corrugated tubular net material is thus obtained.