Multisystem sack closing machines

In the food industry there is increasing demand for different types of sack packaging with the aim of catering for client-specific requirements. In particular, it is a well-known fact that some consumers prefer paper sacks, while others prefer plastic sacks. Because contamination aspects impose serious limitations on the extent to which valve sacks, where switching between paper and plastic sacks is very simple, can be used for food, the problem of changing sack material relates primarily to the open-mouth sack. Since there is often only one bagging machine in a factory, or great flexibility is required when there are more than one, it must be possible for one machine to fill different types of sacks. As a rule this does not pose any problems for the filling operation itself, but it does for closing, since the sack closure and the machine required for it are usually determined by the sack type. Sewing machines have long been used to close a broad spectrum of sack types, but today the requirement is usually for higher-grade closures, making it necessary to ensure availability of the machines needed for the purpose, some of which are highly specialised. For space and cost reasons, combined sack closing machines for two or more types of closure are desirable. In the past this has rarely been put into practice.

MEYPACK, formerly Doboy, has always made machines for all known closure types, so it was logical to combine different closure systems on a single machine frame. The following are some examples:

For many years the S-CH/A-SOT has formed part of the machine programme. This machine seals plastic sacks continuously and can optionally sew paper sacks with overtape.

Similar to this machine, and also in the programme for many years, is the S-CH/D 95 for PE-film and PP woven-fabric sacks.

A sack closing machine was built for a customer in Taiwan that creates a dust-tight or hermetic seal for five different types of sack. Plastic sacks with a film thickness of up to 250 mm are hermetically sealed. The sacks of paper coated woven fabrics which are so popular in Asia, with or without paper or PE inner sack, are stitched and sealed with a PE-coated overtape to produce a dust-tight closure. This machine can also close sacks made of paper/aluminium/PE laminate. A special challenge lies in the fact that the machine also has to close gusseted sacks. In spite of the variety of possible closures and a throughput of 400 sacks per hour, the machine is very compact, with an overall length of 3600 mm.

Another project was the construction of an FTS-BD for a European customer. This machine seals plastic sacks in a continuous process and closes paper sacks using the popular FTS system (fold over twice and secure with sealing tape), enabling it to dispense with stitching systems and their higher maintenance requirements.

The latest multisystem machine is the S-CH/W special, which attracted a lot of attention when it was first presented. As well as sealing plastic sacks, this machine can also seal paper bags with an inner coating after a changeover time of only 20 minutes. A machine of this kind has already been delivered to a customer in France. A special feature of this machine is that instead of the usual conveyor chains it is equipped with toothed belts, which eliminate the need for lubrication.

Since MEYPACK makes machines for all sack closing systems, it can cater for clients' specific wishes for other system combinations.