Posted to News on 1st Jul 2007, 15:09
Web tensioning helps optimise papermaking
Two web tension systems from Vishay Systems are being used by Paprican in a papermaking machine that the organisation operates with a view to optimising the papermaking process.
Vishay Intertechnology has successfully installed two web tension systems at the pilot papermaking machine operated by Paprican (Pulp and Paper Research Institute of Canada). Each of the two web tension systems includes two Vishay Systems model HTU transducers and one model LCt-104 signal conditioner/transmitter. The pilot papermaking machine, located in Pointe-Claire, Quebec, Canada, is used to test and develop new papermaking processes.
The equipment was installed as part of an agreement with Paprican. Although the agreement covers an initial three-year period, the Vishay Systems equipment could remain in place for 25-30 years, depending on the ongoing performance of the equipment and the papermaking machine.
Each of the model HTU web tension transducers has a dual-axis design that measures horizontal and vertical forces, which enables the measurement of resultant force in any direction. It handles capacities from 2000 to 20,000 pounds (9kN to 89kN), is functional to 250degF (121degC), is sealed to meet IP67 requirements, and has a low profile that enables direct load cell replacement. More information is available at www.vishay.com/doc?12192.
Each of the model LCt-104 multi-zone web tension transmitters can handle inputs from two HTUs, or one tension zone, to ensure maximum operating speeds without felt breakage. Each zone is measured with 750,000-count resolution and produces a corresponding high-resolution output of 4-20 mA. The model LCt-104 web tension transmitter features 100 per cent digital calibration with no dead-weight loading and no strapping required. Interface options include Allen-Bradley Remote I/O, Modbus, DeviceNet and Profibus. More information is available at www.vishay.com/doc?12151.
The equipment measures and controls the tension in the forming section of the Paprican papermaking machine (the forming section is where paper pulp is jetted onto a continuous fabric belt). The papermaking machine has multiple belts that are pressed together to extract water from the pulp. The Paprican machine is used to test and develop new papermaking processes. Good measurement and control is critical in the forming section.
Many sensor technologies will not survive in this harsh environment, yet the Vishay Systems equipment will allow Paprican to control web tension and, ultimately, optimise the papermaking process.
About Paprican
Paprican, the Pulp and Paper Research Institute of Canada, is a leading not-for-profit research and technology institute that provides valuable technology transfer and cost-competitive research addressing both the short-term and strategic needs of its members. It has been in business for more than 80 years, with its research programs driven by the high-priority technical issues of the industry - such as product quality and value, cost-competitiveness, environment, and sustainability.
Paprican also offers results-oriented services to members and partners, as well as customers from various industries. Internationally recognised for excellence, Paprican operates laboratories in Quebec and British Columbia, and is well positioned to offer services to the global pulp and paper industry. Paprican is part of FPInnovations.
