﻿UNITED STATES DEPARTMENT OF AGRICULTURE 



DEPARTMENT BULLETIN No. 1136 



Washington, D. C. 



May 12, 1923 



KILN DRYING HANDBOOK 



ROLF THELEN, In Charge, Section of Timber Physics, Forest Products Laboratory, Forest Service 



CONTENTS 



Page 



Purpose 1 



Moisture in wood 1 



Genera I principles of drying wood 5 



Heatinthekiln 6 



Humidity in the kiln 14 



Air circulation! n the kiln 20 



Drying and drying stresses . . 23 



Drying schedules 31 



Kilntypes 45 



Pilingl umber for kiln drying S3 



Details of kiln operation 56 



Air seasoning 63 



WASHINGTON 



GOVERNMENT PRINTING OFFICE 



1923 



