At the end of this module, you will be able to:
- Define the terms "paper," "board," "furnish," "broke," and "white water"
- Identify the effect of each section of the paper machine on the sheet being produced
- Identify the processes associated with each section of the paper machine
- Describe the different types of forming sections, including Fourdrinier, cylinder, paperboard, and twin wire
- Describe the dryer sections on multi-cylinder and Yankee machines
The following key questions are answered in this module:
What is typically contained in a papermaking ""furnish""?
"Furnish" refers to the suspension of fibers, fillers, and chemical additives in water that is used to produce a sheet of paper or board. Furnish components vary according to the desired sheet properties for different paper grades.
What is the function of the headbox on a paper or board machine?
The headbox distributes the furnish evenly onto a continuously moving fine mesh screen (also referred to as a "forming fabric" or "wire") at one end of the machine.
Why is it important to remove as much water as possible at the ""wet end"" of a paper or board machine?
It is desirable to remove as much water as possible at the wet end (which consists of the forming section and press section), because the removal of water by mechanical means costs less than the removal of water by evaporation, which is used in the next section - the dryer section.
What is the purpose of the white water system on a paper or board machine?
The white water system collects much of the water that is removed from the sheet on the machine and makes it available for re-use as dilution water and shower water
Below is a transcript of the video sample provided for this module:
Paper and board are made by the same basic process. First, a suitable furnish is prepared and stored in the machine chest. "Furnish" refers to the suspension of fibers, fillers and additives in water that is used to produce the sheet.
Furnish components vary according to the desired sheet properties, and they differ for different paper grades. The furnish is pumped to the paper machine at a controlled consistency and flow rate in order to produce a sheet of the desired basis weight at the current machine speed.
The two steps just described take place in the stock preparation and stock approach systems, which are covered in separate training modules. This module will describe what happens next in the paper or boardmaking process.
Use the additional resources and links below to learn more about this topic: