GB/T 20241-2021Laminated veneer lumber (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1.Structure and Drafting Rules of Standardization Documents"

Drafting.

This document replaces GB/T 20241-2006 "Laminated Veneer Lumber", compared with GB/T 20241-2006, except for structural adjustment and editorial

In addition to the changes, the main technical changes are as follows.

a) Added terms and definitions such as secondary glued laminated veneer lumber, secondary glued shear strength, dry state, wet state, high humidity state, etc.

(See 3.5~3.9);

b) Added the classification according to the use environment and whether the secondary bonding (see 4.2, 4.3), and deleted the classification according to whether the flame retardant treatment (see.2006

Version 4.4);

c) Added the quality requirements for the inner veneer of non-structural laminated veneer lumber (see 5.1.3.2), and the veneer quality requirements of laminated veneer lumber for structural use

Requirements (see 5.2.3.2), the appearance quality requirements for non-structural laminated veneer lumber (see 5.1.4, 5.1.3 of the.2006 edition) are changed, and the

The appearance technical conditions of laminated veneer lumber for structural use (see 5.2.4 of the.2006 edition);

d) The specifications and deviation requirements are changed (see 5.1.5, 5.2.5, and 5.1.4 and 5.2.5 of the.2006 edition);

e) The performance requirements and inspection methods for formaldehyde emissions have been changed (see 5.1.6.3, 6.3.8, and 5.1.5.3 and 6.1.3.4 in the.2006 edition), and added

The formaldehyde emission performance requirements of laminated veneer lumber for structural use (see 5.2.6.7);

f) The performance requirements and inspection methods of the anti-insect treatment have been changed (see 5.1.6.4, 6.3.9, 5.2.6.3.5, 6.2.3.6 in the.2006 edition);

g) The 130E requirements for elastic modulus and static flexural strength have been added (see 5.2.6.4);

h) The performance requirements and inspection methods for cold water immersion peeling, boiling immersion peeling, and reduced pressure and pressure immersion peeling have been added (see 5.2.6.2 and

6.3.3.2, 6.3.3.3, 6.3.3.4);

i) The performance requirements and inspection methods for the horizontal compressive strength have been added (see 5.2.6.5, 6.3.6);

j) The performance requirements and inspection methods for the secondary bonding shear strength have been added (see 5.2.6.6, 6.3.7);

k) The anti-corrosion performance requirements and inspection methods of laminated veneer lumber for structural use have been added (see 5.2.6.8, 6.3.10).

This document is drafted with reference to ISO 18776.2008 "Specification for Laminated Veneer Lumber", and the degree of consistency is non-equivalent.

Certain contents of this document may involve patents. The issuing agency of this document is not responsible for identifying patents.

This document was proposed by the State Forestry and Grassland Administration.

This document is under the jurisdiction of the National Wood-based Panel Standardization Technical Committee (SAC/TC198).

Drafting organizations of this document. Research Institute of Wood Industry, Chinese Academy of Forestry, Nanjing Forestry University, Lulin Wood Industry (Linyi) Co., Ltd.,

Taizhou Kemian Wood Co., Ltd., Jiangsu Fuqing Wood Co., Ltd., Guannan Yindelong Wood Co., Ltd., National Wood-based Panels and Wood and Bamboo Quality

Quantity Supervision and Inspection Center, Zhejiang Academy of Forestry Sciences, Guangxi Guigang Hanbang Wood Industry Co., Ltd., Shuyang County Peony Wood Industry Co., Ltd.

1 Scope

This document specifies the terms and definitions, classification, requirements, test methods, inspection rules, as well as marking, packaging, transportation and

Storage etc.

This document applies to laminated veneer lumber for non-structural use and laminated veneer lumber for structural use.

2 Normative references

The content of the following documents constitutes an indispensable clause of this document through normative references in the text. Among them, dated quotations

Only the version corresponding to the date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to

This document.

GB/T 1939-2009 Wood horizontal grain compression test method

GB/T 2828.1-2012 Sampling inspection procedures by attributes Part 1.Batch inspection sampling searched by acceptance quality limit (AQL)

plan

GB/T 17657-2013 Test method for physical and chemical properties of wood-based panels and facing wood-based panels

GB/T 18259-2018 Artificial board and its surface decoration terms

GB/T 19367-2009 Determination of the size of wood-based panels

GB/T 26899-2011 Glulam for structural use

LY/T 2062-2012 insect-proof plywood

3 terms and definitions

The following terms and definitions defined in GB/T 18259-2018 apply to this document.

3.1

It is a square lumber made of multi-layer whole (or spliced) veneer glued along the grain direction as the main group blank.

[Source. GB/T 18259-2018, 3.5.1]

3.2

Laminated veneer lumber for non-load bearing purposes.

[Source. GB/T 18259-2018,3.5.4]

3.3

It has good water resistance, weather resistance and mechanical properties, and can be used as a laminated veneer material for load-bearing components.

[Source. GB/T 18259-2018,3.5.3]

3.4

Veneerendjointing

The processing process of splicing two or more veneers together along the grain in the length direction, including butt joint, mitre joint, finger joint and overlap joint, etc.