Abstract: A forming shoulder for an HFFS machine comprises a pair of side wires 3a and 3b each comprising an upper limb 11 joined to a lower limb 14 at an elbow 12 and each supported near a respective end of a support bar 16. The width of the tube, defined by side walls where the tube passes inwardly of the two lower limbs 14 and by a floor (defined by the marginal portions of the film 10) and a ceiling (defined by the central portion 10a of the film spanning the gap between the two elbows 12), is adjustable by re-positioning of the side wires 3a and 3b on the support bar 16 and the height of the tube is adjustable by replacement of one pair of side wires by a different pair having an alternative geometry.

Abstract: A machine for packaging articles in continuous tubular material, which may be formed by rolling the marginal edges of a flat web around a succession of the product articles to bring the marginal edges into contact and then sealing them continuously to complete the tube, comprises a pair of transverse sealing jaws 14 and 15 which each include a hemi-cylindrical chamber 24 having gas-pervious walls 16 and defining a cylindrical space 25 initially centrally divided by the film between two successive product articles 1.The film extending diametrically across the space 25 is first of all severed and then suction is applied to the gas-pervious walls 16 to draw the film into contact with the walls 16. To the righthand side of the space 25 is a double impulse sealing system 18, 19 centrally divided by a knife 21 which separates a righthand pack 28 from the film in the space 25, and to the lefthand side of that space 25 is a further double impulse sealing system 18, 20, again with a knife 22 to effect separation.

Abstract: A vacuumizing and sealing operation on a package comprises initially reducing the external pressure on the package, before sealing of the package, to a value at which the flexible film covering of the package is capable of ballooning, and ensuring heating of the flexible film of the package, preferably while an intermediate pressure is maintained (at which intermediate pressure ballooning could just be sustained without excessive evacuation to reduce the thermal capacity of the circulating air). Finally the pressure inside and outside is reduced still further before re-pressurizing.

Abstract: A vacuumizing and sealing operation on a package comprises initially reducing the external pressure on the package, before sealing of the package, to a value at which the flexible film covering of the package is capable of ballooning, and ensuring heating of the flexible film of the package, preferably while an intermediate pressure is maintained (at which intermediate pressure ballooning could just be sustained without excessive evacuation to reduce the thermal capacity of the circulating air). Finally the pressure inside and outside is reduced still further before re-pressurizing.

Abstract: A pouch for containing wine or other oxygen-sensitive liquid is formed from superposed layers of plastic film having welds to define a rectangular pouch with a straight-sided or shallowly tapering passage communicating a main container portion of the pouch with the exterior of the pouch. When the pouch is full, this passage is sealed off by a further weld which is removed by the consumer to allow the consumer to insert a separate valve into the pouch for dispensing of the liquid.

Abstract: A shrink tunnel for use in shrink packaging of articles with shrinkable films comprises a gaseous return flow, having a working section along which gas passes from an inlet to an outlet in a substantially rectilinier direction, and a return section around which the gas is recirculated for heat and velocity boosting prior to the next cycle through the working section.