NZ506496A - Maximising value of sawn timber by measuring modulus of elasticity by stress wave analysis - Google Patents

Maximising value of sawn timber by measuring modulus of elasticity by stress wave analysis

Info

Publication number
NZ506496A
NZ506496A NZ50649600A NZ50649600A NZ506496A NZ 506496 A NZ506496 A NZ 506496A NZ 50649600 A NZ50649600 A NZ 50649600A NZ 50649600 A NZ50649600 A NZ 50649600A NZ 506496 A NZ506496 A NZ 506496A
Authority
NZ
New Zealand
Prior art keywords
board
elasticity
value
measured
stress wave
Prior art date
Application number
NZ50649600A
Inventor
William D Snyder
Elmer Christensen
Stanley L Floyd
Larry H Jones
Calvin K Kendall
Billy B Pearce
Everette Shaw
Michael J Yancey
Original Assignee
Weyerhaeuser Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=23499442&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=NZ506496(A) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Weyerhaeuser Co filed Critical Weyerhaeuser Co
Publication of NZ506496A publication Critical patent/NZ506496A/en

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Landscapes

  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)

Abstract

The modulus of elasticity (MOE) of a board is determined by striking one end of the board with a pneumatic hammer, and measuring the velocity of the resultant stress waves. This stress wave velocity (SWV) can be used to determine the MOE, which can then be used by a computerized lumber breakdown unit to maximize the value of timber cut from the board. The SWV is measured by a signal acquisition unit 22 that is moved up against one end of a board 50. The distance moved is measured, together with the distance to the other end of the board measured by laser 24. This enables the length of the board to be determined so that the SWV can be measured with the aid of accelerometer in the signal acquisition unit 22 which is moved in to contact with the end of the log.
NZ50649600A 1999-08-24 2000-08-22 Maximising value of sawn timber by measuring modulus of elasticity by stress wave analysis NZ506496A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US37997499A 1999-08-24 1999-08-24

Publications (1)

Publication Number Publication Date
NZ506496A true NZ506496A (en) 2002-08-28

Family

ID=23499442

Family Applications (1)

Application Number Title Priority Date Filing Date
NZ50649600A NZ506496A (en) 1999-08-24 2000-08-22 Maximising value of sawn timber by measuring modulus of elasticity by stress wave analysis

Country Status (2)

Country Link
CA (1) CA2316046C (en)
NZ (1) NZ506496A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7017413B2 (en) * 2004-03-31 2006-03-28 Weyerhaeuser Company Methods for quantitatively determining lengthwise shrinkage in wood products

Also Published As

Publication number Publication date
CA2316046C (en) 2006-01-24
CA2316046A1 (en) 2001-02-24

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Effective date: 20130719

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