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© ISO 2017 Conveyor belts — Transverse flexibility (troughability) — Test method Courroies transporteuses — Flexibilité transversale (aptitude à la mise en auge) — Méthode d’essai INTERNATIONAL STANDA[.]
INTERNATIONAL STANDARD ISO 703 Fourth edition 2017-01 Conveyor belts — Transverse flexibility (troughability) — Test method Courroies transporteuses — Flexibilité transversale (aptitude la mise en auge) — Méthode d’essai Reference number ISO 703:2017(E) © ISO 2017 ISO 703 : 017(E) COPYRIGHT PROTECTED DOCUMENT © ISO 2017, Published in Switzerland All rights reserved Unless otherwise specified, no part o f this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission Permission can be requested from either ISO at the address below or ISO’s member body in the country o f the requester ISO copyright o ffice Ch de Blandonnet • CP 401 CH-1214 Vernier, Geneva, Switzerland Tel +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org ii © ISO 2017 – All rights reserved ISO 703:2017(E) Contents Page Foreword iv Introduction v Scope Normative references Terms and definitions Symbols Principle Apparatus (see Figure 1) Test piece Procedure 10 7.1 7.2 Dimensions Conditioning Calculation and expression o f results Test report Bibliography © ISO 2017 – All rights reserved iii ISO 703:2017(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies) The work o f preparing International Standards is normally carried out through ISO technical committees Each member body interested in a subject for which a technical committee 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 o f electrotechnical standardization The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part In particular the different approval criteria needed for the di fferent types o f ISO documents should be noted This document was dra fted in accordance with the editorial rules of the ISO/IEC Directives, Part (see www.iso org/directives) Attention is drawn to the possibility that some o f the elements o f this document may be the subject o f patent rights ISO shall not be held responsible for identi fying any or all such patent rights Details o f any patent rights identified during the development o f the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso org/patents) Any trade name used in this document is in formation given for the convenience o f users and does not constitute an endorsement For an explanation on the meaning o f ISO specific terms and expressions related to formity assessment, as well as information about ISO’s adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html The committee responsible for this document is ISO/TC 41 Pulleys and belts (including veebelts), Subcommittee SC 3, Conveyor belts This fourth edition of ISO 703 cancels and replaces ISO 703:2007, of which it constitutes a minor revision iv © ISO 2017 – All rights reserved ISO 703:2017(E) Introduction A large number o f conveyor belts work in the shape o f a trough I f a conveyor belt is too sti ff transversely it does not rest on the central idler roller when unloaded Its balance is then unstable and it is subject to lateral travel, which may cause its destruction It is possible to make a section o f the conveyor belt take on the shape o f a trough under its own mass, by suspending the section by its edges However, this does not necessarily indicate what happens when the conveyor belt is not carrying a load The results obtained from the test method specified in this document will, however, allow an assessment to be made as to whether the troughing characteristics o f the conveyor belt are suitable for the intended application © ISO 2017 – All rights reserved v ISO 703:2017(E) INTERNATIONAL STANDARD Conveyor belts — Transverse flexibility (troughability) — Test method Scope T h i s c u ment s p e c i fie s a te s t me tho d conveyor b elt, e xpre s s e d a s a ratio , described in ISO 21183-1 NO TE for de term i n i ng the tra n s vers e flexibi l ity (troughabi l ity) o f a F/L T he me tho d i s no t s u itable or va l id for l ight conveyor b elts a s T he tra n s vers e “fle xibi l ity” de ter m i ne d b y the me tho d de s c r ib e d i n th i s c u ment i s o n l y i nd i re c tl y a s s o c i ate d with the i nvers e o f fle xu l mo du lu s a s s p e c i fie d i n I S O 178 N or e s it ta ke i nto co n s ideration the d i fference s i n “fle xibi l ity” a s e xh ib ite d b y th re e -p o i nt a nd strain and the thickness of the test piece fo u r-p oi nt b end i ng , wh ich ta ke s acco u nt o f the fle xu l Normative re ferences T he fol lowi ng c u ments are re ferre d to i n the tex t i n s uch a way th at s ome or a l l o f thei r content s titute s re qu i rements o f th i s c u ment For date d re ference s , on ly the e d ition cite d app l ie s For u ndate d re ference s , the late s t e d ition o f the re ference d c ument (i nclud i ng a ny amend ments) appl ie s ISO 583, Conveyor belts with a textile carcass — Total belt thickness and thickness of constitutive elements — Test methods ISO 7590, Steel cord conveyor belts — Methods for the determination of total thickness and cover thickness ISO 18573, Conveyor belts — Test atmospheres and conditioning periods Terms and definitions No term s and defi nition s a re l i s te d i n th i s c u ment ISO and IEC maintain terminological databases for use in standardization at the following addresses: — IEC Electropedia: available at http://www.electropedia org/ — ISO Online browsing platform: available at http://www.iso org/obp Symbols F ver tic a l defle c tion i n te s t pie ce corre c te d F1 ver tic a l defle c tion i n te s t pie ce, i n m i l l i me tre s (s e e L length o f tes t piece when laid flat, in mil limetres (equivalent to d thickness of the test piece, in millimetres (see Figure 2) for b elt th ickne s s , i n m i l l i me tre s Figures and 2) full width o f ins talled conveyor belt) Principle A test piece, consisting of a transverse section of belt of length, L , is suspended at both ends with the c arr yi ng face upp ermo s t, s o that the upp er e dge s o f the s e end s are i n the s a me hori z onta l p lane © ISO 2017 – All rights reserved ISO 703:2017(E) T he tra n s vers e flexibi l ity (trough abi l ity) i s de term i ne d b y me a s uri ng the ma xi mu m defle c tion, test piece under its own weight It is expressed as the ratio F/L F, of the Apparatus (see Figure 1) 6.1 Two rigid horizontal bars , greater than the test length, L co nveniently s up p o rted The uns up p o rted length o f the b ars s hall b e Two clamps , to be attached to the ends of the test piece, with suspension lugs for attachment to the suspending wires The construction of the clamps shall allow for a rigid bar or straightedge to be placed in contact with the belt, as shown in Figure f 6.2 , to es tab lis h the datum line neces s ary o r meas uring the deflectio n The clamp s s hall b e s u fficiently wide and rigid to maintain the width o f the tes t p ieces fro m 6.3 free curvature, and s hall exert no b ending mo ment which might influence the deflectio n o f the tes t p iece Four steel suspension wires , o f equal length, each with adj us tab le s tirrup s o n b o th ends fo r attachment to the horizontal bars and clamps The attachments to the horizontal bars and clamps should f f vertical during the test no t imp ede the 6.4 ree movement o the adj us tab le s tirrup s when maintaining the s us p ens io n wires in the Means o f measuring the deflection , F1 , to the nearest millimetre (see Figure 2) Dimensions in millimetres Key four steel suspension wires two rigid horizontal bars two clamps plumb line test piece rigid bar to establish datum line Figure — Typical apparatus for measuring transverse flexibility (troughability) © ISO 2017 – All rights reserved ISO 703:2017(E) Test piece 7.1 Dimensions The test piece shall conform to the following requirements: a) its form shall be a rectangular parallelepiped; b) its length, L , shall be the overall width o f the installed conveyor belt, when laid flat; c) its width, in the longitudinal direction of the belt, shall be (150 ± 2) mm; d) its thickness, d, shall be the overall thickness of the conveyor belt 7.2 Conditioning Condition the test pieces in accordance with ISO 18573, using atmosphere A, B or C, and then carry out the tests immediately a fter completion o f the conditioning period Procedure Immediately be fore the test, ensure that the clamps are free to swivel and not exert a bending force on the test piece Measure the flat length, L , of the test piece in millimetres Measure the thickness, d, of the test piece, in millimetres, in accordance with ISO 583 or ISO 7590 Fit the test piece, carrying face uppermost, while in the flat position, into the suspended clamps Allow the test piece to fall under its own weight from the flat position into the troughed position Adjust the apparatus so that the suspending forces act vertically throughout the test period A fter min, measure the vertical deflection, F1 , of the measurement the dimension 0,5 d to give the value for F test piece (see Figure 2) and add to this Key d thickness of test piece F1 vertical deflection datum line Figure — Determination o f deflection, F1 © ISO 2017 – All rights reserved ISO 703:2017(E) Calculation and expression o f results Calculate the value of F from Formula (1): F = F1 + 0,5 d (1) Express the results of the measurements in the form of F/L 10 Test report The test report shall contain the following information: a) reference to this document, i.e ISO 703; b) identi fic ation o f the conveyor b elt te s te d; c) d) e) f) g) the test length, L (see Clause 4); the thickness of the test piece, d (see 7.1); the conditioning atmosphere used (A, B or C); the value of ratio F/L; the date of the test © ISO 2017 – All rights reserved ISO 703:2017(E) Bibliography [1] [2] ISO 21183-1, Light conveyor belts — Part 1: Principal characteristics and applications ISO 178, Plastics — Determination of flexural properties © ISO 2017 – All rights reserved ISO 703:2017(E) ICS 53.040.20 Price based on pages © ISO 2017 – All rights reserved