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1、BRITISH STANDARD BS EN 924:1995 Adhesives Solvent-borne and solvent-free adhesives Determination of flashpoint The European Standard EN 924:1994 has the status of a British Standard Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 06:25:38 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 924:1
2、995 This British Standard, having been prepared under the direction of the Sector Board for Materials and Chemicals, was published under the authority of the Standards Board and comes into effect on 15 April 1995 BSI 02-1999 The following BSI references relate to the work on this standard: Committee
3、 reference STI/52 Draft for comment 92/58004 DC ISBN 0 580 23940 3 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee STI/52, Adhesives, upon which the following bodies were represented: British Adhesives and Sealants Britis
4、h Plastics Federation British Steel Industry Centre for Adhesive Technology Chemical Industries Association Contract Flooring Association Department of the Environment (Building Research Establishment) Department of Trade and Industry (National Physical Laboratory) European Resin Manufacturers Assoc
5、iation Federation of the Electronics Industry Institute of Materials Ministry of Defence Society of Motor Manufacturers and Traders Timber Research and Development Association University of Bristol Welding Institute Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun
6、sheffieldun, na, Tue Nov 07 06:25:38 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 924:1995 BSI 02-1999i Contents Page Committees responsibleInside front cover National forewordii Foreword2 0Introduction3 1Scope3 2Normative references3 3Definition3 4Principle3 5Apparatus3 6Sampling and sample tre
7、atment5 7Procedure5 8Tests for referee purposes6 9Calculation6 10Precision6 11Test report6 Annex A (informative) BibliographyInside back cover Figure 1 Closed cup with fitted stirrer (see 5.1) immersed in the bath4 Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 06:25:38 GMT+00:00 2006, Uncon
8、trolled Copy, (c) BSI BS EN 924:1995 ii BSI 02-1999 National foreword This British Standard has been prepared by Technical Committee STI/52 and is the English language version of EN 924:1994 Adhesives Solvent-borne and solvent-free adhesives Determination of flashpoint, published by the European Com
9、mittee for Standardization (CEN). EN 924 was produced as a result of international discussion in which the United Kingdom participated. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application.
10、 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, pages i and ii, the EN title page, pages 2 to 6, an inside back cover and a back cover. This standard has been updated (see co
11、pyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 06:25:38 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 924 Novembe
12、r 1994 ICS 83.180 Descriptors: Adhesives, solvents, organic compounds, volatile matter, tests, determination, flash point English version Adhesives Solvent-borne and solvent-free adhesives Determination of flashpoint Adhsifs Adhsifs base de solvant et exempts de solvant Dtermination du point dclair
13、Klebstoffe Lsemittelhaltige und lsemittelfreie Klebstoffe Bestimmung des Flammpunktes This European Standard was approved by CEN on 1994-11-24. 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 n
14、ational standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in
15、 any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, I
16、celand, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1994 Copyright reserved
17、to CEN members Ref. No. EN 924:1994 E Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 06:25:38 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 924:1994 BSI 02-1999 2 Foreword This European Standard has been prepared by the Technical Committee CEN/TC 193, Adhesives, the secretariat of which is h
18、eld by AFNOR. 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 May 1995, and conflicting national standards shall be withdrawn at the latest by May 1995. The Annex A is informative and contains a b
19、ibliography. According to the CEN/CENELEC Internal Regulations, 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, Switzerland and Unite
20、d Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 06:25:38 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 924:1994 BSI 02-19993 0 Introduction This European Standard describes one method for the determination of the flashpoint of adhesives containing volatile organic compounds. It is
21、generally equivalent to ISO 1523 Paints, varnishes, petroleum and related products Determination of flashpoint Closed cup equilibrium method. By the procedure specified in this European Standard, differences between test apparatus of various standard designs are minimized by ensuring that the test i
22、s carried out only when the product under test and the air/vapour mixture above it in the test vessel are approximately in temperature equilibrium. 1 Scope This European Standard specifies a method for determining the flashpoint of adhesives containing volatile organic compounds and makes allowance
23、for deviations from standard atmospheric pressure. It applies to solvent-borne and solvent-free adhesives but not to water-borne adhesives containing less than 10 % of solvents. NOTECare should be taken in the interpretation of results obtained from solvent mixtures containing halogenated hydrocarbo
24、ns as such mixtures can give anomalous results (see Annex A). 2 Normative references This European Standard incorporates by dated or undated references, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed here
25、after. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. EN 10661), Adhesives Sampling. EN 1
26、0671), Adhesives Examination and preparation of samples for testing. 3 Definition For the purposes of this standard, the following definition applies. flashpoint (closed cup) minimum temperature to which a product, confined in a closed cup, must be heated for the vapours emitted to ignite momentaril
27、y in the presence of a flame, when operating under standardized conditions NOTEIn this European Standard, the flashpoint is corrected to an atmospheric pressure of 101,3 kPa. 4 Principle The test portion is heated in a suitably designed closed cup by immersing it to the required level in a suitable
28、bath. The temperature of the bath is slowly raised at such a rate that the difference in temperature between the liquid in the bath and the test portion in the cup never exceeds 2 C, and the heating procedure ensures that the temperature of the test portion does not rise more quickly than about 0,5
29、C in 1,5 min (see note 1). During the heating-up period, ignition trials are carried out at intervals of not less than 1,5 min (see note 2). The lowest temperature at which a flash occurs is noted and from this and a duplicate determination the flashpoint of the test product is calculated, corrected
30、 to the standard atmospheric pressure of 101,3 kPa. NOTE 1To ensure that the test is carried out under approximately equilibrium conditions, a slow rate of heating is necessary because of the low thermal conductivity of some products and also because heat transfer by convection is hindered by the hi
31、gh viscosity of many products. Uniformity of temperature throughout the product under test may be assisted by use of a stirring device, which is not operated during an ignition trial. NOTE 2A minimum time interval of 1,5 min is necessary to ensure that a saturation concentration of vapour in the air
32、 space above the test portion is re-established after each ignition trial. 5 Apparatus 5.1 Test cup. A closed cup with an internal level indicator (see Figure 1). Examples of suitable closed cups include Abel, Abel-Pensky and Pensky-Martens. If the adhesive is liable to be affected by the cup materi
33、al, usually copper, an alternative more appropriate cup material, e.g. stainless steel, shall be used. The cup may be fitted with a stirrer to improve uniformity of temperature. If a stirrer originally fitted to the test cup is removed, the aperture in the cover shall be securely plugged before star
34、ting the test. Essentially, the test cup shall be fitted with a cover which carries an opening slide and an ignition device which is inserted to a prescribed level into one of the openings in the cover when a test is made. 1) In course of preparation. Licensed Copy: sheffieldun sheffieldun, na, Tue
35、Nov 07 06:25:38 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 924:1994 4 BSI 02-1999 The equipment is such that an ignition trial can be performed by opening the slide, inserting and removing the nozzle of the ignition device, and closing the slide again, within a period of (2,5 0,5) s. A mechanical
36、ly driven device for opening the slide and applying the ignition device to the air vapour mixture in the cup is permissible and the source of flame for the ignition device may be any suitable flammable gas. Alternatively, an electrical ignition device can be used instead of a flame. 5.2 Bath, contai
37、ning a suitable liquid, capable of being adjusted to the required temperature (see 7.2.1.2) and of adequate heat capacity to meet the requirements of 7.2.3.6. A bath fitted with a stirrer and thermostat of suitable range is convenient. Other procedures for heating the closed cup may be used if the r
38、ate of heating complies with the requirements given in clause 4. 5.3 Thermometers. The test cup (5.1) shall be fitted with a thermometer of appropriate range and dimension that, when immersed in the test portion, measures its temperature with an error no greater than 0,5 C. A thermometer having a gr
39、aduation at each 0,5 C is recommended. The bath (5.2) shall be fitted with a thermometer of equal precision. When required, the accuracy of the thermometers shall be checked against a reference standard by an authorized laboratory using the stipulated immersion. 5.4 Support, for holding the test cup
40、 in the bath (5.2) so that the cover and upper edge are horizontal. The cup is immersed in direct contact with the liquid in the bath in such a position that the level of the test portion in the cup is the same as that of the liquid in the bath (see Figure 1). Figure 1 Closed cup with fitted stirrer
41、 (see 5.1) immersed in the bath. (The stirrer for the bath is not shown.) Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 06:25:38 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 924:1994 BSI 02-19995 6 Sampling and sample treatment 6.1 Take a representative sample of the product to be tested a
42、s described in EN 1066 and examine and prepare it for testing as described in EN 1067. Samples shall not be stored in plastics (polyethylene, polypropylene, etc.) bottles. 6.2 Because of the possibility of loss of volatile constituents, cool the sample container to at least 10 C below the expected f
43、lashpoint before opening it to remove the test portion. The sample shall receive only the minimum mixing treatment to ensure uniformity. Immediately after removal of the test portion, tightly close the sample container to ensure that loss of volatile components from the container is minimized. If th
44、is is not carried out, the product sample shall be deemed unsuitable for further testing. 7 Procedure 7.1 Preliminary test Determine the approximate flashpoint of the sample by one or more preliminary tests. This determines the starting temperature for the definitive test, which shall be (5 1) C bel
45、ow the expected value. 7.2 Definitive test 7.2.1 Preparation of apparatus 7.2.1.1 Set up the apparatus in a draught-free position, e.g. in a hood, and preferably in subdued light. 7.2.1.2 Adjust the temperature of the liquid in the bath (5.2) to (5 1) C below the approximate flashpoint as determined
46、 according to 7.1. 7.2.1.3 Carefully clean and dry the test cup (5.1), its cover and thermometer (5.3). Bring them to approximately the same temperature as the bath in 7.2.1.2. 7.2.2 Test portion 7.2.2.1 Obtain and prepare the test portion in accordance with clause 6, and ensure that at all times du
47、ring this preparation its temperature is at least 10 C below the expected flashpoint temperature. 7.2.2.2 Fill the cup with the test portion until the internal level indicator just disappears under the surface of the liquid. Take care to avoid both the formation of bubbles and contact between the sa
48、mple and the cup wall above the level indicator. If either of these conditions occurs to a significant extent, empty the cup, prepare it again according to 7.2.1.3, and fill it with a fresh test portion. 7.2.3 Determination 7.2.3.1 Immediately after filling the cup, place the cover and thermometer i
49、n position. Support the cup in the bath so that the cover is horizontal and the cup is immersed in direct contact with liquid in the bath and with the surface of the test portion at the same level as that of the liquid in the bath. Confirm that the bath is at the required temperature as defined in 7.2.1.2. 7.2.3.2 Light the flame of the gas ignition device (if used) and adjust it to an approximately spherical shape of diameter (3.5 0,5) mm. 7.2.3.3 As soon as the test portion has attained the same temperature as th
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