End boss (2,9) arranged in an opening of a
composite pressure vessel comprising an inner fluid tight liner (3) and an outer reinforced
polymer layer (1), which end boss comprises a short
pipe section (2) and a lid (9), the lid is arranged at an upper end of the
pipe section (2) that extends outwards from the vessel, the
pipe section (2) is arranged through the opening of the vessel and extends to a lower end where an outwardly extending
flange on the pipe section is arranged between the outer reinforced
polymer layer (1) and the inner liner (3) in the vessel,distinguished in thatthe inner liner (3) extends upwards through the opening of the pipe section to said lid,on the inside of the inner liner, in a distance nearest to the lid, a sealing surface is arranged, the sealing surface lies against the inner liner and has at least one gas tight seal
interfacing against the inner liner as the sealing surface is integrated with the lid or is a sleeve or a pipe section which is sealingly fastened to the lid, andon the outside of the inner liner, in a groove nearest to the lid and pipe section, around the upper end of the pipe section, a pre-tensioning device is arranged (4, 8, 10, 16), which regardless of the pressure in the vessel presses the inner liner (3) against said sealing surface and the at least one gas tight seal (6).
Composite pressure vessel with such end boss.