Gas inflatable barrier sack manufacture involves manufacture of inner and outer tubular sack parts in reinforced flexible plastic, coating inner sack with plastic and inserting into outer sack before joining together

摘要

An outer sack part comprising a flexible plastic tube with reinforcement of flexible material is produced. Simultaneously or immediately afterwards a tubular inner sack part(6) is produced in a similar or different plastic with flexible reinforcement(8). The inner sack part is then completely covered internally and/or externally with a flexible plastic coating. After insertion of the coated inner sack part into the outer sack part both parts are joined together with a gastight seal. The tubular inner sack part(6) is drawn from a reel(9) and fed continuously to a coating or laminating station(10). Following coating or lamination the inner sack part is turned inside out and coaxially inserted into the outer sack. Coating may alternatively be applied to both the inner and outer sides of the inner sack. Coating or lamination thickness is 10-26 microns. An independent claim is included for an inflatable barrier sack comprising two tubular sack parts of flexible plastic, one inside the other. The inner sack has a continuous, smooth walled coating or lamination of flexible plastic on its inner side.