GB/T 1941-2009Method of testing in hardness of wood (English PDF)

Foreword

This revised standard adopts the International Standard ISO 3350. 1975 "Wood static hardness measuring." this standard and ISO 3350. 1975 compared to the main technical content differences are as follows.

--- Modify 6.2, respectively, in each sample should be two chord plane, two-diameter surface and both end faces of each test time (1975 and Excerpts 6.2);

--- Modify 7.3, hardness of the sample moisture content of 12%, shall be type H12 = HW [1 + 0.03 (W-12)] Calculation (1975 and Excerpts of 7.3).

This standard replaces GB/T 1941-1991 "Test Methods for hardness of wood." this standard compared with GB/T 1941-1991, the main changes are as follows.

--- Amend Chapter 3, 4.2 and Fig 1,6.3,7.1 Hemispheric steel indenter (1991 Excerpts of 3,4.2 and 1,6.3 and 7 and FIG. 1);

--- 4.3 modify, wood moisture content determination equipment shall comply with GB/T 1931-2009 the provisions of Chapter 3 (1991 edition and 4.3);

--- Modify 6.2, respectively, in each sample should be two chord plane, two-diameter surface and both end faces of each test time (1991 and Excerpts 6.2);

--- Remove 6.3 "will load readings fill the Appendix A (Supplement) records in the table" (1991 edition and 6.3);

--- Modification 7.2, the test results of two string sample surface, two-diameter surface and both end surfaces depicting mean, as each side of the sample Hardness (1991 edition and 7.2);

--- Edit "8 test results recording and reporting", test results are reported in accordance with Appendix A fill; the test report according to GB/T 1928-2009

7.4 Content guidelines for preparation (1991 and Chapter 8 of this edition);

--- Increase in Appendix A test site, end load, load string side and radial load surface, remove moisture, face hardness, surface hardness and chord diameter Surface hardness (1991 edition and Appendix A).

Appendix A of this standard is a normative appendix.

This standard was proposed by the State Forestry Administration.

This standard by the National Standardization Technical Committee timber.

1 Scope

This standard specifies the determination of test equipment, samples, wood hardness testing procedures, the results of calculations and test results are recorded and reporting.

This standard applies to the small sample timber unblemished surface diameter, chord surface, measuring the end face of hardness.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement are based on research Whether the latest versions of these documents. For undated reference documents, the latest versions apply to this standard.

GB/T 1928-2009 General physical and mechanical test methods (ISO 3129. 1975, Wood-Samplingmethodsand generalrequirementsforphysicalandmechanicaltests, NEQ) GB/T 1929-2009 physical and mechanical test materials and test specimens sawing method (ISO 3129. 1975, Wood-Sampling methodsandgeneralrequirementsforphysicalandmechanicaltests, MOD) GB/T 1931-2009 Method for determination of moisture content of wood (ISO 3130. 1975, Wood-Determinationofmoisture contentforphysicalandmechanicaltests, MOD) Principle 3 Other rigid timber having a resistance pushed with hemispherical steel indenter predetermined radius in the static load under pressure into the timber to indicate their hardness.

4 Test Equipment

4.1 test machine, load measurement accuracy should be consistent with GB/T 1928-2009 Chapter 6 requirements.

4.2 Electric contact type hardness test apparatus comprising a radius of (5.64 ± 0.01) mm steel hemispherical indenter. Allows the use of having the same radius Hemispherical steel indenter other types of test equipment as shown in Figure 1.

Millimeters

1 --- hemispherical steel head;

2 --- adjustment screw (on contact);

3 --- having contact spring means;

4 --- sleeve.

1 electric contact type hardness test equipment