1、BRITISH STANDARDBS EN ISO 8307:2007Flexible cellular polymeric materials Determination of resilience by ball reboundThe European Standard EN ISO 8307:2007 has the status of a British StandardICS 83.100g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g4
2、0g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 8307:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 January 2008 BSI 2008ISBN 978 0 580 55326 4National forewordThis Britis
3、h Standard is the UK implementation of EN ISO 8307:2007. It supersedes BS EN ISO 8307:1998 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee PRI/24, Testing of rigid and flexible cellular materials.A list of organizations represented on this committee c
4、an be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corrigenda issued since pu
5、blicationDate CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 8307December 2007ICS 83.100 Supersedes EN ISO 8307:1997 English VersionFlexible cellular polymeric materials - Determination of resilienceby ball rebound (ISO 8307:2007)Matriaux polymres alvolaires souples - Dterminationde l
6、a rsilience par rebondissement dune bille (ISO8307:2007)Weich-elastische polymere Schaumstoffe - Bestimmungder Kugel-Rckprallelastizitt (ISO 8307:2007)This European Standard was approved by CEN on 24 November 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipul
7、ate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exis
8、ts in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodi
9、es of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPE
10、AN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 8307:2007: E3 Foreword This d
11、ocument (EN ISO 8307:2007) has been prepared by Technical Committee ISO/TC 45 “Rubber and rubber products“ in collaboration with Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by NBN. This European Standard shall be given the status of a national standard, either by publi
12、cation of an identical text or by endorsement, at the latest by June 2008, and conflicting national standards shall be withdrawn at the latest by June 2008. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall
13、not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 8307:1997. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgar
14、ia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text o
15、f ISO 8307:2007 has been approved by CEN as a EN ISO 8307:2007 without any modification. BS EN ISO 8307:2007Reference numberISO 8307:2007(E)INTERNATIONAL STANDARD ISO8307Second edition2007-12-15Flexible cellular polymeric materials Determination of resilience by ball rebound Matriaux polymres alvola
16、ires souples Dtermination de la rsilience par rebondissement dune bille BS EN ISO 8307:2007ii iiiContents Page Foreword iv 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 1 4 Principle. 1 5 Apparatus 1 5.1 General. 1 5.2 Apparatus with manual reading 2 5.3 Apparatus with automatic re
17、ading 3 6 Test pieces 3 7 Number of test pieces 3 8 Test conditions . 3 9 Procedure 4 9.1 Preflex conditioning . 4 9.2 Test method. 4 10 Expression of results . 4 11 Precision 4 12 Test report . 4 Annex A (informative) Example of electronic measurement procedure. 6 BS EN ISO 8307:2007iv Foreword ISO
18、 (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical com
19、mittee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrot
20、echnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the mem
21、ber bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identify
22、ing any or all such patent rights. ISO 8307 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 4, Products (other than hoses). This second edition cancels and replaces the first edition (ISO 8307:1990), which has been technically revised. The main change is th
23、e inclusion of an automatic method, using an electronic sensor, of measuring the ball rebound height. BS EN ISO 8307:20071Flexible cellular polymeric materials Determination of resilience by ball rebound WARNING Persons using this International Standard should be familiar with normal laboratory prac
24、tice. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. 1 Scope This International Standard
25、 specifies a method for determining the resilience by ball rebound of flexible cellular polymeric materials. 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,
26、 the latest edition of the referenced document (including any amendments) applies. ISO 23529, Rubber General procedures for preparing and conditioning test pieces for physical test methods 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 open-
27、cell flexible cellular material flexible cellular material with less than 25 % of its cell volume closed 3.2 closed-cell flexible cellular material flexible cellular material with more than 25 % of its cell volume closed 4 Principle A steel ball is dropped on to a test piece from a specified height
28、and the height of rebound is measured. 5 Apparatus 5.1 General The ball rebound test apparatus (see Figure 1) shall consist of a 30 mm to 65 mm inside diameter vertical transparent tube, into which a 16 mm 0,5 mm diameter steel ball with a mass of 16,8 g 1,5 g is released by a magnet or other suitab
29、le device. The steel ball shall be released so that it falls without rotation and is BS EN ISO 8307:20072 effectively centred. The height of the drop shall be 500 mm 0,5 mm. Since it is most convenient to note the position of the top of the ball on rebound, the top of the ball shall be 516 mm above
30、the surface of the test piece. Thus, “zero” rebound shall be the diameter of the ball above the specimen surface. Measurement errors can arise if the tube is not held in a vertical position, and measurements may be invalid due to contact of the rebounding ball and the inner surface of the tube. It i
31、s therefore important to use a spirit level or similar device to ensure that the tube is mounted at right angles to the rigid baseplate, and that the baseplate itself is horizontal. Dimensions in millimetres Key 1 magnet or other suitable device 2 steel ball 3 transparent tube 4 test piece 5 rigid b
32、aseplate Figure 1 Diagrammatic arrangement of test apparatus 5.2 Apparatus with manual reading The scale on the back of the tube shall be graduated directly in per cent as follows: every 5 % (25 mm) a complete circle shall be scribed and at every 1 % a 120 arc shall be scribed on the tube. The compl
33、ete circles are an essential part of the apparatus, since they are used to eliminate parallax error. BS EN ISO 8307:200735.3 Apparatus with automatic reading A device capable of determining the rebound height of the steel ball by electronic means can also be used, as long as it has been demonstrated
34、 to give the same results as the manual-reading apparatus. The rebound height can be calculated from, for example, the rebound velocity or the time interval between the first and second contacts of the ball with the foam surface (see Annex A). The apparatus can be equipped with any such device provi
35、ded it is capable of determining the rebound height to a precision of 1 % of the total drop height (i.e. 5 mm). For this type of apparatus, the tube does not require graduations. 6 Test pieces 6.1 The test pieces shall have plane, parallel top and bottom surfaces. 6.2 The test pieces shall consist o
36、f the entire product sample or a suitable portion of it, except that in no case shall the thickness be less than 50 mm or the area less than 100 mm 100 mm. Test pieces less than 50 mm thick shall be plied up, without the use of cement, to a minimum of 50 mm. For moulded products, the top skin shall
37、be removed. NOTE The minimum test piece thickness of 50 mm may not be sufficient for very soft materials: if spuriously high results are obtained, a thicker test piece can be used. Very low density materials may also cause problems due to rebound of the test piece itself. With multiple-ply test piec
38、es, slipping can occur between the plies. This problem can be overcome by using the largest possible area of test piece. 7 Number of test pieces Three test pieces per sample shall be tested. The three test pieces may be obtained by using separate items or different locations on a given item. 8 Test
39、conditions Material shall be tested not less than 72 h after manufacture, unless, at either 16 h or 48 h after manufacture, it can be demonstrated that the mean rebound resilience values obtained do not differ by more than 10 % from those obtained after 72 h. Testing is permitted at either 16 h or 4
40、8 h if, at the selected time, the above criterion has been satisfied. Prior to the test, the test pieces shall be conditioned undeflected and undistorted for at least 16 h in one of the following atmospheres as given in ISO 23529: 23 C 2 C, (50 5) % relative humidity; 27 C 2 C, (65 5) % relative hum
41、idity. This period can form the latter part of the period following manufacture. In the case of quality-control tests, test pieces can be taken a shorter time (down to a minimum of 12 h) after manufacture and testing carried out after conditioning for a shorter period (down to a minimum of 6 h) in o
42、ne of the atmospheres specified above. BS EN ISO 8307:20074 9 Procedure 9.1 Preflex conditioning Open-cell material as defined in 3.1 shall be subjected to preflex conditioning before testing. Preflex the test piece by compressing it twice to 75 % to 80 % of its original thickness at 0,4 mm/s to 6 m
43、m/s, then allow the test piece to recover for a period of 10 min 5 min. NOTE This preflex conditioning is not applicable to closed-cell material as defined in 3.2. 9.2 Test method 9.2.1 Carry out the test immediately after conditioning, preferably in the same atmosphere as was used to condition the
44、test pieces (see Clause 8). 9.2.2 Centre the test piece at the base of the tube (see Clause 5) and adjust the height of the tube so that zero rebound is 16 mm 0,5 mm above the surface of the test piece. Clamp the tube to make light contact with the test pieces without causing visible compression. 9.
45、2.3 Mount the steel ball on the release mechanism, then drop it and note the maximum rebound height to the nearest percentage point. If the ball strikes the tube on the drop or rebound, the value obtained is invalid. This condition is usually due to the tube not being vertical or to irregularities o
46、n the test piece surface. In order to minimize parallax error, the eye-level of the observer shall be such that the markings on the tube in the region where the percentage rebound value is read appear as straight lines. Trial drops are necessary in order to establish the correct eye-level. 9.2.4 At
47、least three rebound values in succession within 1 min shall be obtained on each of the three test pieces. 10 Expression of results For each test piece, determine the median of the three rebound height values. If any value deviates by more than 20 % (one-fifth) of the median value from the median, ma
48、ke two additional drops and determine the median for all five rebound height values. Using the median values obtained for the three test pieces, determine the overall median value as the rebound resilience value of the material. If automated measurement is employed, the results shall also be express
49、ed to the nearest integer. 11 Precision At the present time, precision data are not available for this test method. 12 Test report The test report shall include the following information: a) a reference to this International Standard; b) a description of the material tested, including whether open-cell or closed-cell as defined in Clause 3; c) the temperature and humidity at which the test piece was conditioned and tested; d) whether or not electronic measurement was used; BS EN ISO 8307:20075e) the rebound resilience
