Fabrication of expandable polystyrene plastic ignition containers

Claim 1

A method for fabrication of an expandable polystyrene plastic ignition container, said container having the weight, density, and strength requirements to function in a high length to diameter rocket flight motor and to remain intact until all parts of a contained ignitor charge is ignited and which said expandable polystyrene plastic ignition container subsequently breaks up into small pieces to that plugging of the nozzle of said rocket flight motor does not occur, said method comprising completing the method steps set forth under parts A, B, and C stages as follows: Part A, pre-expanding stage consisting of: (i) selecting a first predetermined quantity of a heat expandable polystyrene in the form of minute unexpanded beads; (ii) placing said predetermined quantity of heat expandable beads in boiling water; (iii) expanding said beads to approximately three times their original size; (iv) draining off excess water; Part B, blending stage consisting of: (i) selecting a second predetermined quantity of a heat expandable polystyrene in the form of minute beads; (ii) combining said first predetermined quantity of a heat expandable polystyrene in said pre-expanded form with said second predetermined quantity of a heat expandable polystyrene and mixing thoroughly to yield a twinned polystyrene beads blend consisting of about 4.5 parts by weight of said pre-expanded polystyrene beads and of about 10 parts by weight of said heat expandable polystyrene in the form of minute beads; and, Part C, molding and heat forming stage consisting of: (i) adding a predetermined quantity of said blend of twinned polystyrene beads into a casting mold of a predetermined shape for said ignitor casting container component; (ii) placing said mold containing said twinned polystyrene beads into a steam chamber; (iii) admitting steam to said steam chamber to pressurize to 250° F. with 15 psig steam; (iv) retaining said mold containing said twinned polystyrene beads under said pressurized steam for about three miutes; (v) removing said mold from said steam chamber; (vi) placing said mold containing said twinned polystyrene beads in an expanded stage into cold water for about one minute; and (vii) removing polystyrene plastic ignitor casing container from said mold.

Claim 2

A method for fabrication of an expandable polystyrene plastic ignition container, said container having the weight, density, and strength requirements to function in a high length to diameter rocket flight motor and to remain intact until all parts of a contained ignitor charge is ignited and which said expandable polystyrene plastic ignition container subsequently breaks up into small pieces to that plugging of the nozzle of said rocket flight motor does not occur, said method comprising completing the method steps set forth under parts A, B, and C stages as follows: Part A, pre-expanding stage consisting of: (i) selecting a first predetermined quantity of a heat expandable polystyrene in the form of minute unexpanded beads; (ii) placing said predetermined quantity of heat expandable beads in boiling water; (iii) expanding said beads to approximately three times their original size; (iv) draining off excess water; Part B, blending stage consisting of: (i) selecting a second predetermined quantity of a heat expandable polystyrene in the form of minute beads; (ii) combining said first predetermined quantity of a heat expandable polystyrene in said pre-expanded form with said second predetermined quantity of a heat expandable polystyrene and mixing thoroughly to yield a twinned polystyrene beads blend consisting of about 4.5 parts by weight of said pre-expanded polystyrene beads and of about 10 parts by weight of said heat expandable polystyrene in the form of minute beads; and, Part C, molding and heat forming stage consisting of: (i) adding a predetermined quantity of said blend of twinned polystyrene beads into a casting mold of a predetermined shape for said ignitor casting container component; (ii) placing said mold containing said twinned polystyrene beads into a steam chamber; (iii) admitting steam to said steam chamber to pressurize to 250° F. with 15 psig steam; (iv) retaining said mold containing said twinned polystyrene beads under said pressurized steam for about three miutes; (v) removing said mold from said steam chamber; (vi) placing said mold containing said twinned polystyrene beads in an expanded stage into cold water for about one minute; and (vii) removing polystyrene plastic ignitor casing container from said mold.