LY/T 1738-2020 in English

ChinaStandards.net is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.

This standard is developed in accordance with the rules given in GB/T 1.1-2009.

This standard is a revision of LY/T 1738-2008 Plywood for solid wood composite flooring. The following main technical changes have been made with respect to LY/T 1738-2008:

——The definition of no-added formaldehyde plywood for parquet is added;

——The classification is modified.

——The requirements for specification and dimension deviation are modified;

——The requirements for pin knots, live knots, abnormal structure of wood and other defects in the appearance quality are deleted;

——The bonding strength requirement in the physical and chemical properties is deleted;

——The inspection method and requirements of formaldehyde emission are modified;

——The size and quantity of dimensional stability test pieces;

——The schematic diagram for specimen sawing is added;

——The sampling plan for appearance quality inspection and specification and dimension deviation inspection is added;

——The identification, packaging and transportation requirements are modified.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.

This standard was proposed by and is under the jurisdiction of SAC/TC 198 National Technical Committee on Wood-based Panels of Standardization Administration of China.

The previous edition of this standard is as follows:

——LY/T 1738-2008.


Plywood for parquet

1 Scope

This standard specifies the classification, requirements, inspection methods, inspection rules, and identification, packaging, transportation and storage of plywood for parquet.

This standard is applicable to plywood for parquet.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 2828.1-2012 Sampling procedures for inspection by attributes - Part 1: Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection
GB/T 9846-2015 Plywood for general use
GB/T 17657-2013 Test methods of evaluating the properties of wood-based panels and surface decorated wood-based panels
GB/T 18103-2013 Engineered wood flooring
GB/T 18259-2018 Terminology for wood-based panels and their surface decoration
GB 18580 Indoor decorating and refurbishing materials - Limit of formaldehyde emission of wood-based panels and finishing products
GB/T 19367-2009 Wood-based panels - Determination of dimensions of panels

3 Terms and definitions

For the purposes of this document, the terms and definitions given in GB/T 18259-2018 and the following apply.

3.1
plywood for parquet
plywood for parquet made by veneer assembly and gluing

3.2
no-added formaldehyde plywood for parquet
plywood for parquet without adding any adhesive or auxiliary agent containing formaldehyde component in the preparation process

 
4 Classification

4.1 By the type of adhesive:

a) no-added formaldehyde plywood for parquet;

b) added formaldehyde plywood for parquet.

4.2 By the service environment:

a) Type I plywood: used outdoors;

b) Type II plywood: used in humid conditions.

5 Requirements

5.1 Specification and dimension deviation

The specification and dimension deviation of plywood for parquet shall be in accordance with those specified in Table 1.

Table 1 Specification and dimension deviation of plywood for parquet
Item Requirement
Thickness deviation The difference between the average thickness da and the nominal thickness dn is 0mm~0.3mm;
The difference between the maximum dmax and the minimum dmin of the inner thickness of the plywood shall not be greater than 0.3mm.
Length deviation The absolute value of the difference between the nominal length ln and the average length la shall not be greater than 5mm, and negative deviation is not allowed.
Width deviation The absolute value of the difference between the nominal width wn and the average width wa shall not be greater than 3mm, and negative deviation is not allowed.
Verticality deviation ≤ 1mm/m
Edge straightness deviation ≤ 1mm/m
Warping degree ≤ 0.75%

5.2 Appearance quality

The appearance quality of plywood for parquet shall be in accordance with those specified in Table 2.

Foreword II
1 Scope
2 Normative references
3 Terms and definitions
4 Classification
5 Requirements
6 Inspection methods
7 Inspection rules
8 Identification, packaging, transportation and storage