Abstract: A valve bag having an upper bottom with a valve and a lower bottom symmetrically folded in a manner where the bottoms lie atop the central bag portion in a side-by-side and parallel manner is provided.

Abstract: Apparatus for folding paper sacks to a Z shape about transverse fold lines comprises scoring wheels for defining the fold lines, folding blades and folding means consisting of folding bars for turning the sacks about the folding blades. A first double belt conveyor clampingly engages each sack near its base or filling aperture and conveys it continuously through the folding means. Two parallel shafts mounted in the machine frame in a vertical plane transverse to the conveying direction each carry two spaced co-operating scoring wheels which provide the passing sacks with scoring in opposite senses. A second double belt conveyor provided parallel to the first engages the sacks at the opposite end, has a length equal to the scoring and holds each sack while passing through the scoring wheels. A third double belt conveyor adjoining the second and parallel to the first clamps each sack between the first double belt conveyor and the scoring facing same during folding about this scoring.

Abstract: Apparatus to seal the valve of a valve bag with adhesive and of the kind where bag arrives from bagging machine standing up or somewhat reclining. The apparatus comprises adhesive sprayer (9) over which and fitted thereto a shield (23) with bow-shaped cross-section and rounded front is mounted so that the fronts of shield (23) and sprayer (9) are flush over and under each other, or so that the shield (23) protrudes in front of sprayer (9). The assembly comprising shield (23) and sprayer (9) is suspended or has organs to move it in a way that the assembly during insertion into the valve (6) describes a bow-shaped motion (A) in the vertical middle of the bag valve and so that the assembly lifts up the valve (6) when inserted. The adhesive sprayer (9) is designed to apply adhesive onto the lower inside of the bag valve (6).According to one special embodiment the adhesive sprayer can turn or rotate round its own axis in order to apply a consistent strip of adhesive.

Abstract: Before piling or stacking the bags, the intermediate part (1) of the bag lying between the reinforced or thickened top and/or bottom part (2,3) is folded so as to create a layer having a thickness corresponding to the thickness of the top and/or bottom parts (2,3) where these are folded flat against the bag or sack. Consequently, the bags can be stacked in great numbers without upsetting the stack or distorting the shape of it.