News: Kilndrying.org passes 100,000 total viewsFrench Language Discussion


Author Topic: Causes of variability in hemlock  (Read 1418 times)

Offline MichaelM

  • Forum Expert
  • Kiln Drying Enthusiest
  • *****
  • Posts: 57
    • View Profile
Causes of variability in hemlock
« on: June 16, 2011, 09:41:29 AM »
Adin Berberovic at OSU completed a thesis last year in which the factors affecting hemlock drying were studied.  Mills often presort based on initial MC (or weight) but other work in the past suggests that the wettest heaviest boards going in are not the wettest boards coming out.  We were looking for some other measurable wood factor that causes boards to reach the final moisture content at different times.  Then, instead of sorting based on weight or initial moisture content, one could sort on expected drying time.

Dr. Berberovic dried matched samples at 220F and 180F.  Each board was continuously weighed during drying.  Basic density, initial moisture content, percentage of heartwood, position of heartwood within a board, ring count, rings from the pith, growth ring angle, and earlywood and latewood coverage on board faces were measured on each board.  At the lower temperature basic density, initial moisture content, heartwood percentage, and growth ring angle affected the drying rate.  At high temperature, only the initial moisture content affected the drying rate.   Modeling with both the drying rate and initial moisture contents suggests that sorting based on both specific gravity and initial moisture content reduces final moisture content variability better than sorting on any one criterion.

The complete thesis is available at http://ir.library.oregonstate.edu/xmlui/handle/1957/17702
A shorter publication will be out later this year.

Linkback: http://www.kilndrying.org/moisture-variability/4/causes-of-variability-in-hemlock/259/

Offline Neissa G

  • Administrator
  • Newbie
  • *****
  • Posts: 9
    • View Profile
Re: Causes of variability in hemlock
« Reply #1 on: October 14, 2013, 03:11:07 PM »
I just came across this study...very interesting.

Thanks for sharing!
NG


Share via facebook Share via furl Share via linkedin Share via reddit Share via twitter
 


Forum experts

MichaelM lmod MichaelM
Michael Milota Ph.D.
Professor
Oregon State University
READ BIO
PhilM lmod PhilM
Phil Mitchell Ph.D.
Forum Expert
North Carolina State University
READ BIO
PierreA lmod PierreA
Pierre Asselin ing.f.
Forum Expert
READ BIO
StavrosA lmod StavrosA
Stavros Avramidis Ph.D.
Professor
University of British Columbia
READ BIO
TimothyD lmod TimothyD
Timothy Duncan MBA
Engineering Manager
Wagner Meters
READ BIO

* Events


* Job Opportunities

topic Kiln Operator - McCormick, SC
[Job Postings]
admin
September 11, 2014, 08:32:04 AM
topic Kiln Supervisor - Plymouth, NC
[Job Postings]
admin
September 10, 2014, 03:05:57 PM
topic Boiler/Kiln Operator Trainee - Plummer, ID
[Job Postings]
admin
September 10, 2014, 02:43:18 PM