|
||||||||||||||||||||
4. Determine Drying RH Settings
|
||||||||||||||||||||
28mm (4/4") white oak. |
|
Temperature set point |
45 C or 115 F |
Current MC% in the core |
21% |
Oak belongs to specie group |
4 |
Suggested drying gradient for |
1.5 to 2.0 |
Drying gradient |
1.7 Example. |
Calculated EMC% of the air |
12.4 EMC% |
Use EMC graphto determine |
approx. 72% RH |
The relative humidity setting should be. |
72% |
If the MC% of the wood is above 28% you must use 28% in your calculation. When drying lumber, the shrinkage starts around 28%, this is the reason why MC% above 28% is considered 28% for purposes of calculating the RH settings. We are trying to prevent the excess shrinkage of the shell (in comparison to the core) to be stretched beyond the breaking point when surface checking starts.
Kiln-direct believes this is the best method to determine the relative humidity or depression schedule for species and thicknesses that you cannot find good and accurate existing data. Using this method does require a thorough understanding of kiln theory and very close attention during the first drying cycles to insure that drying defect and other degrade becomes excessive.
We hope this information meets with your expectation and approval. We always welcome your opinions and suggestions. You can email us at techsupport@kiln-direct.com. Thank you for your continued interest.
New Wood waste heat system for your kiln and warehouse - See test pictures.
New SlimLine Heat recovery systems added to our product line - See Online Store.
September 9th-11th: Lake State Logging Congress and Equipment Expo - Green Bay, WI - come visit us at our booth.
September 17th-18th: Kentucky Wood Expo 2010 - Madisonville, KY - come visit us at our booth.
October 1st-3rd: Paul Bunyan Show - Cambridge, OH - come visit us at our booth.
Copyright 2002-2010 Kiln-direct.com
All rights reserved
Powered by SalesKite