Over-drying

It is presumed that the crown and loading at the presses are correct and consequently, moisture is even into the dryers.
1. Maintain a close check on the reel and instruments.
— traversing moisture and basis weight gauges should be installed.
— if moisture profile is poor, the conditions causing the poor profile must be removed.
2. Provide automatic dryer control.
— it is human nature to keep out of trouble and if the machine will not permit even drying, then the operator will dry down until a good reel can be built. In this case, automatic control will give no improvement.
— modem automatic systems control drying by controlling the air supplied to the pocket ventilation system.
3. Maintain correct volume, humidity, and temperature of supply air for ventilation.
— exhaust at the recommended humidity and ensure that ventilation system is working as designed.
— ensure that system is in balance with no excessive air currents up sides of hood.
— do not use hood to exhaust machine room.
4. Ensure that felt air is evenly distributed and that dryer felt tensions are even.
5. A good pocket ventilation system coupled with an efficient economizer will improve the operation and capacity while providing warm water for critical shower applications.
6. Install and maintain an adequate steam supply and condensate removal system.
7. Over-drying increases sheet brittleness and leads to calender cuts, etc.