The valve sack experts: W&H offers more than just machines

The market for industrial packaging is full of different valve sack concepts for paper, woven plastics and plastic films. There are a number of reasons for this, such as different applications, availability of the respective materials, or even regional differences, sometimes with historical root causes. Since A.M. Bates first introduced the valve sack concept back in the 1920s, Windmöller & Hölscher has been a reliable partner for the sack and bagging industry. Based in the Westphalian town of Lengerich, the German family-owned company offers a machine solution for every concept, as well as support with sack development and concept evaluation. And with its new AD proFilm MP film valve sack, W&H is taking another step.

The AD proFilm MP sack is manufactured on the AD PLASTIC 2 valve bottomer. The machine, launched in 2015, is unusual in that it uses hot air to seal the sacks. This means that it does not require adhesives, which can be the source of significant production costs and technical process limitations.

When the company was developing the new AD proFilm MP film valve sack, it chose to focus on two key factors: high moisture protection (MP = moisture proof), and extending the product’s shelf life. It achieved this through the use of its innovative Breathing Chamber Technology – a ventilation chamber along the longitudinal seam of the sack. “This technology means that effective ventilation and high moisture protection are no longer mutually exclusive", explains Uwe Köhn, Head of Processing Products at Windmöller & Hölscher.

Valve sacks have the important benefit of being able to be filled on nozzle packers, which ensure a high filling output. But although paper, woven plastics and plastic film sacks all have this one factor in common, each material has its own specific advantages. Paper valve sacks are a comparatively cost-effective form of packaging made from a renewable source. Windmöller & Hölscher is the market leader in the field of paper sack systems, with a market share of more than 90%. Woven plastic valve sacks are very lightweight and tear-resistant, which is particularly useful if the sacks are to be used in tougher environments. Film valve sacks, on the other hand, provide excellent moisture protection and advertising on them is more effective as they hold print so well, a factor which is key, particularly in the field of premium packaging.

W&H offers machine solutions tailored to each of the three concepts, and so can always provide the ideal machine for any sack application. And the company’s services do not stop at the machine. It offers a complete package that includes everything from formula development and drop tests to comprehensive advice and support, so the customer can be sure that they are making the right investment decision for their packaging needs.