Key Questions
The following key questions are answered in this module:
What is the main advantage of a shoe press over roll press?
With the increased nip width, the dwell time (the amount of time that the sheet is exposed to the nip pressure) is up to 10 times longer
On which grades are shoe presses used?
Shoe presses were initially used on machines producing heavier weight grades, like board and corrugating medium. They are now used effectively in making printing, writing, and tissue, as well as container board and carton board, grades.
What are shoe press sleeves made out of?
Most shoe press sleeves are made from a woven substrate with a coating of polyurethane, which may be grooved, blind drilled, or smooth.
What are the functions of the hydraulic fluid in a typical shoe press?
The hydraulic fluid is used to pressurize the shoe loading pistons, provide lubrication for the shoe-to-sleeve interface, and provide cooling.
Does the entire shoe press rotate during press operation?
No. The roll journals, heads, and sleeve rotate around the stationary support beam and press shoe assembly.