Patent ID: 8647457

Claim:
A method of manufacturing rubber lined composite pressure vessels, the method including the steps of: providing a mold ( 1 ) with a ring ( 13 ); providing a rubber sheet ( 2 ) with an annular flange ( 21 ) in the mold ( 1 ) so that an annular flange ( 21 ) of the rubber sheet ( 2 ) is located on the ring ( 13 ); providing tapes ( 22 ) for attaching the annular flange ( 21 ) to the ring ( 13 ); inserting a metal socket ( 23 ) in an aperture defined in the rubber sheet ( 2 ); providing a metal cap ( 24 ) for covering the metal socket ( 23 ); providing a vacuum bag ( 3 ) for enclosing the rubber sheet ( 2 ) and the mold ( 1 ); heating, pressing and therefore vulcanizing the rubber sheet ( 2 ); removing the vacuum sheet and the metal cap ( 24 ), thus providing a semi-product of the rubber liner; inserting a rod ( 4 ) in the semi-product ( 2 a ); providing a sand mold ( 41 ) in the semi-product ( 2 a ) by filling sand ( 41 ) in the semi-product ( 2 a ), making the sand ( 41 ) compact, and drying the sand ( 41 ); removing the rod ( 4 ); cutting the annular flange ( 21 ); assembling the semi-product ( 2 a ) against a second semi-product ( 2 a ); providing rubber solvent on portions of each of the two semi-products ( 2 a ) that are located against each other; providing a rubber band ( 5 ) on the rubber solvent so that the two semi-products ( 2 a ) are joined together forming a semi-products assembly ( 2 b ); inserting a mandrel ( 6 ) in the semi-products assembly ( 2 b ); winding a filament ( 61 ) on the semi-products assembly ( 2 b ); heating and hence vulcanizing the rubber band ( 5 ) and curing the filament ( 61 ); then removing the mandrel, and dissolving the sand mold ( 41 ) in water and hence removing the sand mold ( 41 ).