Harro Hoefliger recently were faced with the challenge of building a machine to double bag trays of prefilled syringes (PFS).
The machine operates in sterile and receives incoming trays of assembled syringes to be double bagged for aseptic filling at another site. Stacks of presterilised bags were taken and automatically opened by the machine with vacuum and specially designed opening forks. The tray of syringes was then inserted and the end of the bag pulled tight and crease free for sealing with cGMP design of impulse welding tools.
As premade bags off the reel have no defined shape or position, particular care had to be taken throughout the process when handling to ensure the complete process, both the bags and the syringe trays, were under control at all times with no possibility of snagging. Considerable special design went into the control and guiding of the bag edges and the syringe tray infeed. Total seal integrity was of course a given.
An elegant solution to double bagging was found. The single bagged syringe tray was then retracted and a second bag pulled, the tray pushed into the second bag and this bag too was sealed.