Fully automated paper strength tester increases product consistency and reduces waste
 

ABB, one of the leading power and automation technology groups, is helping paper manufacturers assess uniform strength across the entire reel width of a wide range of paper and board grades, quickly, accurately and simply via its L&W ZD Tensile Tester.

The tester overcomes the time-consuming, complex and manual approach of the traditional Scott Bond method that takes fewer measurements leading to unreliable results.

The tester’s accuracy means paper makers can now achieve a more consistent final product quality and reduce wastage.

The tester measures internal bond strength values – or Z-direction (ZDT) tensile forces – using a simple, automated method. The paper sample to be tested is placed on the device’s feeding table and the operator presses the start button. Tape is automatically applied on both sides of the sample. Steel platens are pressed against the taped paper/board sample. The platens then pull the paper apart and the force needed to split the sample is recorded. The sample is automatically fed to the next measurement position. The results are displayed in tabular form or as graphics and can be output using the built-in printer. Measurement of a 1.5m strip in 10 positions takes only six minutes. The system operates in accordance with ISO 15754, SCAN P 80 and TAPPI T 541 standards.

By testing the internal bond strength, paper makers can avoid low or unevenly distributed bonds that cause material splitting in an offset press with sticky printing ink.

The tester also ensures that, when creasing or scoring boxboard, the material delaminates to the right degree, thereby avoiding poor folding lines or cracks in the outer layer, leading to waste. Too high internal bond strength impedes the creasing of the boxboard which leads to material wastage and excessive energy use.

In heat-set web offset printing of highly coated paper, a good internal bond strength is critical to avoid blistering occurring as moisture escapes during the heating process. The tester can identify when this is likely to occur.

The tester comes with a colour touch screen with intuitive menus, large accessible buttons and a protective surface for easy cleaning. In addition to printing via the built-in printer, the system offers the functionality to export data via Ethernet or to print on a network device instead.