A fold-type piercer sealing system, comprising a sealing film (130) and a guarding apparatus (150), the sealing film (130) being connected to the guarding apparatus (150). The sealing film (130) comprises a proximal extremity opening (132), a distal extremity opening (133), and sealing walls (135) extending from the distal extremity opening (133) to the proximal extremity opening (132), the sealing walls (135) being provided with a proximal extremity surface and a distal extremity surface, and the distal extremity opening (133) being formed by a sealing lip (134). The guarding apparatus (150) comprises a proximal extremity (152), a distal extremity (154), and a columnar wall (159) extending from the distal extremity (154) to the proximal extremity (152). The sealing walls (135) comprise multiple folds (140). The folds (140) are externally tangential to the sealing lip (134) and extend transversely outwards. Each fold (140) comprises a fold peak (142), a fold trough (144), and a fold wall (143) extending from the fold peak (142) to the fold trough (144). Also, the folds (140) surround the sealing lip (134) in an overall disk-shaped arrangement. The columnar wall (159) of the guarding apparatus (150) comprises folds (160) identical in number to and matching in shape and size with the sealing walls (135). The present system reduces curve accumulation and winding of the guarding apparatus (150) and the sealing film (130), thus reducing the frictional resistance when flipped inwards.Un système détanchéité pour perceur pliable, comprenant un film détanchéité (130) et un appareil de protection (150). Le film détanchéité (130) est connecté à lappareil de protection (150) et comprend une ouverture à lextrémité proximale (132), une ouverture à lextrémité distale (133), et des parois détanchéité (135) sétendant de louverture de lextrémité distale (133) à louverture de lextrémité proximale (132). Les parois détanchéité (135) sont pourvues dune surface à lextrémité proximale et
