2018 International Forest Industries IFI Feb March 2018 Digital | Page 35

The sawmill THG works in tandem with the Edger BioVision system at Kiwi. The THG has significantly improved the accuracy of the grade output
Duncan reports that now both Edger
BioVision and THG systems are operating as
anticipated. “Overall the edger’s been a good
project for us, and it’s given us a good payback.
It’s still relatively early days, but we see the THG
giving us a good payback too.” And he related
that integration with the acoustic grader is
also working as expected. There is a software
upgrade that is due to be implemented on the
edger, that will incorporate new algorithms for
further improved grade accuracy. Duncan said
that overall the vision scanning projects were
very worthwhile investments.
One key reason for determining the grade
in the sawmill is the opportunity to accurately
identify the true value of the piece at an earlier
stage in the process. If you can sell it green,
you may be able to recoup a higher value and
not add cost through drying and planing. If you
believe it will make the SG8 grade, and go to the
expense of drying and planing it, then discover it
doesn’t make the grade, you’ve lost time, you’ve
lost value and you’ve added cost.
Challenges and opportunities
With any new technology but particularly true
with automated grading software, development
can be an ongoing process. Duncan described
one example. “On the edger we had specific
challenges around the knots that project
through the wane, and with blonde knots.
Additional development work was done by
USNR to detect those knots.” USNR’s Stephen
Wardrop, optimization technician, spent time
working at site with the Kiwi team to further
tune the systems for improved knot detection.
He continued, “Both systems presented
challenges, and I think that’s because of the
complexity of tuning the systems to what we
wanted to accomplish. Every site is unique, and
looking back on the projects now, I think they
went as well as they could have.”
Describing the future outlook for
the Masterton operation, given the new
technologies that have been implemented,
Duncan related, “This new scanning technology
opens up other opportunities for us to consider
in terms of grades or products which we haven’t
produced before, but may be able to now.
We can also refine our own grading rules to a
degree, which we couldn’t do before.”
Ongoing evolution
The vision scanning upgrades in the sawmill
puts the Masterton operation in an enviable
position to be able to capitalize on its improved
output. In 2018 Duncan revealed the mill is
upgrading its primary breakdown line with a
new log infeed and log handling equipment from
USNR.
USNR’s experience in vision scanning
includes over 110 installations of systems
worldwide. A significant number is in the
Australia / New Zealand region, with 20 systems
now operating. With this much experience, USNR
is a strong partner to consider when planning
your next project.
Kiwi Lumber is a privately owned New Zealand
company operating three modern sawmills
located in the North Island of New Zealand.
It’s three mills located at Putaruru, Dannevirke
and Masterton have a combined production of
120,000 m3 of sawn timber output per annum,
with the capacity to kiln dry and planer finish all
of it’s production.
The sawmills are strategically situated close
to the large commercial plantings in the Hawke’s
Bay/Wairarapa and the Central Plateau of the
North Island. These areas represent significant
commercially grown forests, which are well
serviced by professional contractors, harvesters
and forest managers to ensure that customers
have access to some of the best renewable
timber resources available.
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