Abstract: A web of interconnected plastic bags with gusset folds. Each bag is provided with first fold part seals (8, 9, 10, 11) and with second fold part seals (13, 14, 15, 16). Additional seals (36) extend parallel to fold edges of the foil and are connected with subsequent first and second fold part seals. The additional seals (30) are in the region between inner (4, 4a) and other (2, 3 and 2a, 3a) fold edges.

Abstract: A web of interconnected plastic bags with gusset folds. Each bag is provided with first fold part seals (8, 9, 10, 11) and with second fold part seals (13, 14, 15, 16). Additional seals (36) extend parallel to fold edges of the foil and are connected with subsequent first and second fold part seals. The additional seals (30) are in the region between inner (4, 4a) and outer (2, 3 and 2a, 3a) fold edges.

Abstract: A web of interconnected plastic bags produced by providing a tubular foil of plastic material with gusset folds with bottom fold part seals at both sides of the tubular foil. Each fold part seal connects a gusset fold part with an opposite part of the outer foil layers. Immediately after having moved the tubular foil over a predetermined distance the tubular foil is provided with a first transverse bottom seal by heatsealing opposite first fold part seals and outer foil layers to each other.

Abstract: The raised edge part of a deep-drawn plastic cover is printed by pressing a carrier of a resilient deformable material, carrying a coloring composition, against the raised edge part.An apparatus for manufacturing the plastic cover comprises a deformable carrier for carrying a coloring composition. The carrier is integral with a cylindrical part connected with a first cylinder. Two concentric cylinders, positioned around the first cylinder at either side thereof, deform annular parts of resilient material and press these annular parts against the raised edge part when, on the one hand, the first cylinder and, on the other hand, the two concentric cylinders are moved with respect to each other.The coloring composition may also be carried by a layer-shaped carrier material.

Abstract: A socket of a thermoplastic pipe is provided with an internal groove by subjecting the tube to an upsetting action and simultaneously inflating the tube by an inner pressure. Subsequently a moulding ring is expanded and the tube is shrunk onto the expanded ring by cooling. Before shrinkage the inner diameter of the bottom of the groove is at least equal and preferably greater than the outer diameter of the moulding ring in expanded form.