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Pulp and Paper Playing a Crucial Role in Global Bioeconomy, Paper360º January/February 2022

Pulp and Paper Playing a Crucial Role in Global Bioeconomy, Paper360º January/February 2022

Should Maintenance Cost be Benchmarked?, Paper360º January/February 2022

Should Maintenance Cost be Benchmarked?, Paper360º January/February 2022

TAPPI Journal Summaries, Paper360º January/February 2022

TAPPI Journal Summaries, Paper360º January/February 2022

Turning Pulper Rejects into Valuable Fuel, Paper360º January/February 2022

Turning Pulper Rejects into Valuable Fuel, Paper360º January/February 2022

Web lateral instability caused by nonuniform paper properties, TAPPI Journal January 2022

ABSTRACT: Lateral or cross-machine direction (CD) web movement in printing or converting can cause problems such as misregistration, wrinkles, breaks, and folder issues. The role of paper properties in this problem was studied by measuring lateral web positions on commercial printing presses and on a pilot-scale roll testing facility (RTF). The findings clearly showed that CD profiles of machine direction (MD) tension were a key factor in web stability. Uneven tension profiles cause the web to move towards the low-tension side. Although extremely nonuniform tension profiles are visible as bagginess, more often, tension profiles must be detected by precision devices such as the RTF. Once detected, the profiles may be analyzed to determine the cause of web offset and weaving problems.Causes of tension profiles can originate from nonuniform paper properties. For example, by means of case studies, we show that an uneven moisture profile entering the dryer section can lead to a nonuniform tension profile and lateral web movement. Time-varying changes in basis weight or stiffness may also lead to oscillations in the web’s lateral position. These problems were corrected by identifying the root cause and making appropriate changes. In addition, we developed a mathematical model of lateral stability that explains the underlying mechanisms and can be used to understand and correct causes of lateral web instability.

The Future of Water for the Pulp and Paper Industry, Paper360º July/August 2022

The Paper360° 2022 TOP 50 POWER LIST, Paper360º July/August 2022

Efficiency is Key for High Capacities, Paper360º March/April 2022

Efficiency is Key for High Capacities, Paper360º March/April 2022

OSHA Updates: What’s in Store For 2022, Paper360º March/April 2022

OSHA Updates: What’s in Store For 2022, Paper360º March/April 2022

SETPOINT: Let’s Finally Talk About Bruno, Paper360º March/April 2022

SETPOINT: Let’s Finally Talk About Bruno, Paper360º March/April 2022