Plastic tanks

Claim 1

A CONTAINER FOR FLUIDS COMPRISING A GLASS FIBER REINFORCED CLOSED HOLLOW PLASTIC SHELL HAVING AN ELONGATED TUBULAR PORTION TERMINATING IN A CIRCUMFERENTIAL PERIPHERY AT EACH END OF SAID TUBULAR PORTION AND END PORTIONS BEING CURVED TO DEFINE SAID SUBSTANTIALLY CLOSED HOLLOW SHELL, SAID SHELL COMPRISING A THERMOSETTING ISOPHTHALIC POLYESTER RESIN DISTRIBUTED THROUGHOUT THE SHELL IN PERMEATING RELATIONSHIP WITH A PLURALITY OF LAYERS OF REINFORCING GLASS FIBERS SHAPED TO THE FORM OF SAID TUBULAR PORTION AND SAID CURVED END PORTIONS AND INCLUDED IN SAID RESIN, THE OUTER PORTION OF SAID LAYERS CONSISTING OF HELICALLY-WOUND GLASS FILAMENT FORMING A HELICAL PATTERN, SAID FILAMENT EXTENDING AT AN ANGLE OF BETWEEN ABOUT 5* AND 90* WITH RESPECT TO THE LONGITUDINAL AXIS OF SAID SHELL, SAID TUBULAR PORTION INCLUDING A PLIRALITY OF INTEGRALLY FORMED REINFORCING RIBS, SAID RIBS DISPOSED OUTWARDLY FROM THE EXTEROIR OF SAID SHELL IN SPACED RELATIONSHIP ALONG THE LONGITUDINAL AXIS OF SAID TUBULAR PORTIONS, SAID CURVED ENDS INCLUDING A SANDWICH WITH AN INNER LAYER CONSISTING OF SAID SHELL, AN OUTER LAYER CONSISTING OF A THERMOSETTING ISOPHTHALIC POLYESTER GLASS FIBER-REINFORCED PLASTIC LAMINATE SPACED FROM SAID INNER LAYER TO ACCOMMODATE A CORE OF MATERIAL, SAID CORE OF MATERIAL BEING OF RELATIVELY LOW STRUCTURAL STRENGTH AND LAMINATED BETWEEN SAID INNER LAYER AND SAID OUTER LAYER TO FILL SAID SPACE AND FORM SAID CORE, SAID OUTER LAYER JOINED AT SAID PERIPHERY TO SAID REINFORCING RIBS ADJACENT THE CURVED ENDS.