A novel system is described for manufacturing fully automatically pressure units (1) having a high pressure container (2) with a bottom part (3) and a closure (7) with a pressure control device (6), which pressure units (1) are to be mounted in a fluid container (5). In a production line (100) with a first station (110) the bottom part (3) and the closure (7) are mounted automatically to the high pressure container (2). In a second station (130) the bottom part 3) and the closure (7) are welded into the high pressure container (2), and in a third station (160) the containers (50) and the pressure units (1) are pre-assembled. In a fourth station (170) the pressure units (1) are welded into the containers (50).