Author: Tuomas Tiainen

How Product Variations Can Cause Winder Vibration

Laboratory setup of a Tapio Analyzer at Aalto University, showing the winding frame, caliper measurement system and multi-probe roundness measurement equipment.

How Product Variations can Cause Winder Vibration A winder–cutter is not an easy system to optimize. Changing web tensions, roll diameters, masses and rotational frequencies all interact, and the behaviour of the machine changes continuously during the winding cycle. This makes it challenging to avoid resonances and unwanted vibration. During the past year, the Tapio […]

Roll Hardness Profiles – What Can the Statistics Tell Us?

Example of device screen showing a roll hardness profile graph with major variations, including mean, standard deviation, coefficient of variation, minimum, maximum, and peak-to-peak hardness values.

Roll Hardness Profiles – What Can the Statistics Tell Us? Quality of rolls is not about appearance – it depends both on the rolled material and on how the roll has been wound. The hardness profile provides valuable insight into roll condition and helps detect faults that are often invisible to the eye or missed […]

Optimizing paper and board machine CD profiles with Tapio Analysis

Graph showing excess basis weight in cross-direction (CD) paper profile leading to fiber overuse and potential savings of approximately 7800 t/a.

Optimizing paper and board machine CD profiles with Tapio Analysis In modern paper production, achieving an efficient and accurate cross-direction (CD) profile is critical for product quality and production cost control. In typical production lines, online scanners provide the operators with the CD profile. However, online QCS (Quality Control System) scanners have inherent limitations: they […]

Locate problematic machine elements using Tapio MD Analysis

Diagram showing a web passing through rolls with quality variations and geometry errors, illustrating how machine direction frequency stays at 1 Hz even as velocity and wavelength change.

Locate problematic machine elements using Tapio MD Analysis In paper, board, and other continuous production processes where the product is formed by rolling or pressing, every rotation of any mechanical element affecting the web — such as a roll, felt, wire, or pump — leaves a repeating pattern related to quality variation on the final […]

Hidden defects in rolls: a closer look with Tapio RQP Live

A person in a high-visibility vest measuring the hardness of a large paper roll using the Tapio RQP Live handheld device.

Hidden defects in rolls: a closer look with Tapio RQP Live A paper, board or plastic roll may appear perfectly fine on the outside. The surface layers may seem to be uniform, smooth, and free of any obvious defects. However, beneath the outer layers, hidden issues can exist that compromise the performance and quality of […]

Hidden roll defects are costing you more than you think

A visual comparison showing a plastic roll that appears uniform, a wrinkled sheet when unrolled, and a hardness profile graph revealing defects along the CD position.

Every mill knows the frustration of a “bad” roll — unscheduled downtime, customer complaints, wasted materials, and production delays. But what if you could detect roll defects before they cause expensive problems? The good news: you can. And it starts with understanding roll hardness profiles.