Optimising Paper Machine Felt Change Schedules
نویسنده
چکیده
To make paper, machines spray wet pulp on a moving screen and extract the water from it by squeezing it between rollers, before drying it using heat and rolling it on reels as finished product. The water extracted in the squeezing process is removed by a continuous roll of fabric called a felt. There are typically three felts on a paper machine. Felts wear out over time, and therefore must be replaced, either at a planned machine shutdown or at some other time when the machine fails randomly. All machine stoppages incur a downtime cost. This paper presents a stochastic dynamic programming model for determining a felt replacement policy that minimises the expected felt cost and cost of downtime.
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