Lightweight cylinder construction

A hollow cylinder having an axis of rotation and comprising:

• (a) a hollow cylindrical member having radially inner and outer faces and formed of a plurality of interengaging modules each extending parallel to said axis of rotation of said cylinder and assembled in side-by-side relationship in a circular array, each said module having spaced wall portions which, in the assembled configuration of the cylinder, define at least part of said radially inner face of the modular cylinder and said radially outer face thereof;
• (b) end plates connected to ends of said modules;
• and
• (c) means for stressing the modules to have said wall portions defining the radially outer face of the modular cylinder stressed in compression and said wall portions defining the radially inner face of the modular cylinder stressed in tension.

A hollow cylinder having an axis of rotation and comprising:

• (a) a hollow cylindrical member having radially inner and outer faces and formed of a plurality of interengaging modules each extending parallel to said axis of rotation of said cylinder and assembled in side-by-side relationship in a circular array, each said module having spaced wall portions which, in the assembled configuration of the cylinder, define at least part of said radially inner face of the modular cylinder and said radially outer face thereof;
• (b) end plates connected to ends of said modules;
• and
• (c) at least one reinforcement ring as a tight fit within said hollow cylindrical member and engaging said radially inner face thereof at a location between the ends of each module.

A hollow cylinder having an axis of rotation and comprising:

• (a) a hollow cylindrical member having radially inner and outer faces and formed of a plurality of interengaging modules each extending parallel to said axis of rotation of said cylinder and assembled in side-by-side relationship in a circular array, each said module having spaced wall portions which, in the assembled configuration of the cylinder, define at least part of said radially inner face of the modular cylinder and said radially outer face thereof;
• (b) end plates connected to ends of said modules;
• and
• (c) means for stressing the modules to have said wall portions defining the radially outer face of the modular cylinder stressed in compression and said wall portions defining the radially inner face of the modular cylinder stressed in tension, wherein the means for stressing the modules comprise filler means to be inserted at a respective interface between adjacent modules, near said radially outer face of the modular cylinder to cooperate with said filler means of the other interfaces whereby insertion of the last said filler means places the entire cylinder under the desired stress.