Wet End Edge Trimming

At the beginning of the forming section of a paper or board machine, deckles and curling boards keep the stock on the wire until it has sufficiently dewatered and solidified. At the other end of the former, the trim squirts trim off the edges of the sheet before it transfers to the press section. This establishes the sheet width all the way to the reel. The deckles and trim squirts must be set up correctly, and the trim squirt nozzles and water supply system must be regularly monitored to ensure the cleanliness of the edge cuts and trouble-free sheet transfer into the press section.

•Define sheet "formation" •Explain why wet end edge trimming is important on a paper or board machine •Identify and describe the functions of deckle boards, trim squirts, and wire cleaning showers •Identify the trim squirt system parameters that are important to monitor during production •Identify and describe the equipment (showers) used to remove the trimmed edges from the wire