BS EN 322-1993 Wood-based panels Determination of moisture content《木基板 水分含量测定》.pdf

1、BRITISH STANDARD BS EN 322:1993 Wood-based panels Determination of moisture content The European Standard EN 322:1993 has the status of a British Standard UDC 674.815:620.168.334BS EN322:1993 This British Standard, having been prepared under the directionof the Technical Sector Board for Building an

2、d Civil Engineering (B/-), was published under the authority ofthe Standards Board and comesintoeffect on 15 April 1993 BSI 07-1999 The following BSI references relate to the work on this standard: Committee reference B/541 Draft for comment 90/11135 DC ISBN 0 580 21057 X Cooperating organizations T

3、he European Committee for Standardization (CEN), under whose supervision this European Standard was prepared, comprises the national standards organizations of the following countries: Austria Oesterreichisches Normungsinstitut Belgium Institut belge de normalisation Denmark Dansk Standardiseringsra

4、ad Finland Suomen Standardisoimisliito, r.y. France Association franaise de normalisation Germany Deutsches Institut fr Normung e.V. Greece Hellenic Organization for Standardization Iceland Technological Institute of Iceland Ireland National Standards Authority of Ireland Italy Ente Nazionale Italia

5、no di Unificazione Luxembourg Inspection du Travail et des Mines Netherlands Nederlands Normalisatie-instituut Norway Norges Standardiseringsforbund Portugal Instituto Portugus da Qualidade Spain Asociacin Espaola de Normalizacin y Certificacin Sweden Standardiseringskommissionen i Sverige Switzerla

6、nd Association suisse de normalisation United Kingdom British Standards Institution Amendments issued since publication Amd. No. Date CommentsBS EN322:1993 BSI 07-1999 i Contents Page Cooperating organizations Inside front cover National foreword ii Foreword 2 Text of EN 322 3 National annex NA (inf

7、ormative) Committees responsible Inside back coverBS EN322:1993 ii BSI 07-1999 National foreword This British Standard has been prepared under the direction of the Technical Sector Board for Building and Civil Engineering and is the English language version of EN322:1993, Wood-based panels Determina

8、tion of moisture content, published by the European Committee for Standardization (CEN). EN 322 was produced as a result of international discussion in which the UK took an active part. The principle of the method is technically equivalent to A.5 of BS1142:1989 Specification for fibre building board

9、s and to clause 9 of BS5669 Particleboard Part 1:1989 Methods of sampling, conditioning and test, and to Appendix A of BS6556 Plywood Part5:1985 Specification for moisutre content, all of which will be withdrawn in due course. A British Standard does not purport to include all the necessary provisio

10、ns of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theEN title page, pag

11、es 2 to4, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 322 February 1993 UDC 674.815:62

12、0.168.334 Descriptors: Wooden boards, fibre boards, plywood, determination, humidity English version Wood-based panels Determination of moisture content Panneaux base de bois Dterminationdelhumidit Holzwerkstoffe BestimmungdesFeuchtegehaltes This European Standard was approved by CEN on 1992-12-15.

13、CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on a

14、pplication to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat h

15、as the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Sta

16、ndardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1993 Copyright reserved to CEN members Ref. No. EN 322:1993 EEN322:1993 BSI 07-1999 2 Foreword This European Standard was prepared by Working Group4 “Common test method

17、s” (Secretariat:United Kingdom) of Technical Committee CEN/TC112 “Wood-based panels” (Secretariat:Germany). The text is based on ISO9425:1989 which has been elaborated with European participation. This Standard is one of a series of standards specifying methods of test for determining dimensions and

18、 properties of wood-based panels. No existing European Standard is superseded. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by August1993, and conflicting national standards shall be withdrawn at

19、the latest by December1994. In accordance with the Common CEN/CENELEC Rules the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerla

20、nd and United Kingdom. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Principle 3 4 Apparatus 3 5 Test pieces 3 6 Procedure 3 7 Expression of results 3 8 Estimation of board moisture content 3 9 Test report 3 Annex A (informative) Bibliography 4EN322:1993 BSI 07-1999 3 1 Scope This Eu

21、ropean Standard specifies a method for determining the moisture content of test pieces of wood-based panels. Such result may be used to estimate the moisture content of wood-based panels according to EN 326-1. 2 Normative references This European Standard incorporates by dated or undated reference,

22、provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard, only when incorporated i

23、n it by amendment or revision. For undated references the latest edition of the publication referred to applies. EN 326-1, Wood-based panels Sampling, cutting and inspection Part 1: Sampling and cutting of test pieces and expression of test results 1) . 3 Principle Determination, by weighing, of the

24、 loss of mass of each test piece between its state at the time of sampling and its state after drying to constant mass at(103 2) C, and calculation of this loss of mass as a percentage of the mass of the test piece after drying; these results are used to estimate the moisture content of whole boards

25、. 4 Apparatus 4.1 Balance Balance, scale interval0,01g. 4.2 Drying oven Ventilated drying oven, capable of being controlled at(103 2) C. 4.3 Desiccator Silica gel containing a desiccant, to maintain the air as close as possible to the absolutely dry condition. 5 Test pieces 5.1 Sampling and cutting

26、Sampling and cutting of the test pieces shall be carried out in accordance with EN326-1. Test pieces shall cover the full thickness of the board. 5.2 Dimensions The test piece shall have a minimum initial mass of20g:shape and size are unimportant. The test pieces shall be free from loose splinters a

27、nd sawdust. 6 Procedure 6.1 Weighing before drying Weigh each test piece in the as-sampled state to an accuracy of0,01g. This initial weighing shall be carried out immediately after sampling or where this is impossible, precautions shall be taken to avoid changes in the moisture content of the test

28、piece after sampling. 6.2 Drying Place the test pieces in the drying oven(4.2) at a temperature of(103 2) C until constant mass has been reached. Constant mass is considered to be reached when the results of two successive weighing operations, carried out at an interval of6h, do not differ by more t

29、han0,1% of the mass of the test piece. 6.3 Weighing after drying After the test pieces have been cooled to approximately room temperature in the desiccator(4.3), weigh each test piece to an accuracy of0,01g, rapidly enough to avoid an increase in moisture content greater than0,1%. 7 Expression of re

30、sults Calculate the moisture content H of each test piece, as a percentage by mass to the nearest0,1%, in accordance with the following formula: where 8 Estimation of board moisture content The moisture content of a board shall be obtained by calculating the arithmetic mean of the moisture contents

31、of all the test pieces taken from the same board and shall be expressed as a percentage to one decimal place. 9 Test report As described in EN326-1. 1) At present at the draft stage m H is the initial mass of the test piece, ingrams m 0 is the mass of the test piece after drying, ingrams H m H m 0 m

32、 0 -100 =EN322:1993 4 BSI 07-1999 Annex A (informative) Bibliography EN 309, Particleboards Definition and classification. EN 313-1, Plywood Classification and terminology Part 1: Classification. EN 316, Wood fibreboards Definitions, classification and symbols. EN 633, Cement-bonded particleboards D

33、efinition and classification 2) . ISO 9425, Wood-based panels Determination of moisture content. 2) At present at the draft stageBS EN322:1993 BSI 07-1999 National annex NA (informative) Committees responsible The United Kingdom participation in the preparation of this European Standard was entruste

34、d by the Technical Sector Board for Building and Civil Engineering (B/-) to Technical Committee B/541, upon which the following bodies were represented: American Plywood Association Association of British Plywood and Veneer Manufacturers British Woodworking Federation Chartered Institute of Building

35、 Co-ordinator for Timber and Timber Products Council of the Forest Industries of British Columbia Department of the Environment (Timber Division Building Research Establishment) Fibre Building Board Organisation (FIDOR) Finnish Plywood International Flat Roofing Contractors Advisory Board Forestry C

36、ommission Furniture Industry Research Association Institution of Structural Engineers National Federation of Roofing Contractors National House-building Council National Panel Products Association Royal Institute of British Architects Timber Research and Development Association Timber Trade Federati

37、on United Kingdom and Ireland Particleboard Association Coopted memberBSEN 322:1993 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the inter

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