Skip to main content
SpringerLink
Log in

Effect of speed on the accuracy of stress-grading machines for lumber

  • Published:
Wood Science and Technology Aims and scope Submit manuscript

Summary

A computer simulation model is developed for predicting modulus of elasticity (E) of uniform lumber measured at high speed by stress-grading machines of the constant-deflection type. Simulations carried out with the model showed that speed had no significant effect on the average E measured along the lumber but largely affected E values measured at individual locations. Tests conducted at 15, 150 and 315 m/min with two machines employing different supports conditions confirmed model predictions. Ability of the grading machines to identify local E values at high speed could be improved by proper filtering of the load signal recorded by the machine.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Hoyle, R. J., Jr. 1961: A nondestructive test for stiffness of structural lumber. Forest Prod. J. 11: 251–254

    Google Scholar 

  • Hoyle, R. J., Jr. 1968: Background to machine stress grading. Forest Prod. J. 18 (4): 87–97

    Google Scholar 

  • Kaliteevskii, R. E.; Ogurtsov, V. V. 1975: Effect of the speed of longitudinal lumber movement on stress-grading parameters. Lesnoi Zhurnal 5: 134–138 (In Russian)

    Google Scholar 

  • Logan, J. D. 1978: Machine stress rating. Proceedings of the 4th Nondestructive Testing of Wood symposium. Vancouver, WA., pp. 285–303

  • Mote, C. D., Jr. 1965: Some dynamic characteristics of band saws. Forest Prod. J. 15 (1): 37–41

    Google Scholar 

  • Mote, C. D., Jr. 1968: Dynamic stability of an axially moving band. J. of the Franklin Institute 285: 329–346

    Google Scholar 

  • Pellerin, R. F. 1976: Non-destructive evaluation of wood and wood products. Proceedings from IUFRO Wood Engineering Group meeting, Denmark/Norway, Paper 19

  • Pelster, S. 1963: The Stress O-Matic stress rating system. Proceedings of the symposium on Nondestructive Testing of wood. Forest Prod. Lab., Madison, WI

    Google Scholar 

  • Reddy, J. N. 1984: An introduction to the finite element method. New York: McGraw-Hill

    Google Scholar 

  • Samson, M. 1985: Finite element model for predicting modulus of elasticity of lumber measured by stress-grading machines. Wood a. Fiber Sc. 17: 490–503

    Google Scholar 

  • Samson, M. 1986: Predicted and actual performance of two laboratory stress-grading machines employing different support conditions. Wood a. Fiber Sc. 18: 478–489

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Quebec, Canada

    M. Samson

Authors
  1. M. Samson
    View author publications

    You can also search for this author in PubMed Google Scholar

Additional information

Experimental data analysed in this paper were collected when the author was a Research Scientist at Forintek Canada Corp., 6620 N.W. Marine Dr., Vancouver, B.C., Canada, V6T 1X2. The author is grateful to H. Fraser and L. S. Olson from Forintek for their assistance in perfoming the experiments. Financial support of the Natural Sciences and Engineering Research Council of Canada is gratefully achnowledged.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Samson, M. Effect of speed on the accuracy of stress-grading machines for lumber. Wood Sci. Technol. 21, 281–292 (1987). https://doi.org/10.1007/BF00351400

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00351400

Keywords

Search

Navigation