1、BSI Standards Publication BS ISO 6502:2016 Rubber Guide to the use of curemetersBS ISO 6502:2016 BRITISH STANDARD National foreword This British Standard is the UK implementation of ISO 6502:2016. It supersedes BS 903-A60.1:2000 which is withdrawn. The UK participation in its preparation was entrust
2、ed to Technical Committee PRI/22, Testing and analysis of rubber. A list of organizations represented on this committee can 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 applicat
3、ion. The British Standards Institution 2016. Published by BSI Standards Limited 2016 ISBN 978 0 580 89437 4 ICS 83.060 Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Commit
4、tee on 29 February 2016. Amendments/corrigenda issued since publication Date T e x t a f f e c t e dBS ISO 6502:2016 ISO 2016 Rubber Guide to the use of curemeters Caoutchouc Guide pour lemploi des rhomtres INTERNATIONAL STANDARD ISO 6502 Fourth edition 2016-01-15 Reference number ISO 6502:2016(E)BS
5、 ISO 6502:2016ISO 6502:2016(E)ii ISO 2016 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2016, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, in
6、cluding 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 ISOs member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerlan
7、d Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.orgBS ISO 6502:2016ISO 6502:2016(E)Foreword iv Introduction v 1 Scope . 1 2 Normative references 1 3 T erms and definitions . 1 4 Basic principles 2 5 Types of curemeter 4 6 Apparatus . 4 6.1 General . 4 6.2 Die cavity 4 6.3 Die c
8、losure 5 6.4 Moving member . 5 6.5 Movement 5 6.6 Stiffness measurement . 6 6.7 Heating and temperature control . 6 6.8 Calibration 6 7 Test piece 6 8 Vulcanization temperature 6 9 Conditioning 6 10 Test procedure 7 10.1 Preparation for the test . 7 10.2 Loading the curemeter . 7 11 Expression of re
9、sults 7 12 Test report . 8 Annex A (informative) Effect of thermal parameters on measured cure properties 16 Annex B (informative) Particular requirements for oscillating-disc curemeters 19 Annex C (informative) Particular requirements for rotorless curemeters .20 Bibliography .21 ISO 2016 All right
10、s reserved iii Contents PageBS ISO 6502:2016ISO 6502:2016(E) Foreword ISO (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 commi
11、ttees. 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 I
12、nternational Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
13、 different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. IS
14、O shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of 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 docu
15、ment is information given for the convenience of users and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trad
16、e (TBT) see the following URL: Foreword - Supplementary information The committee responsible for this document is ISO/TC45, Rubber and rubber products, Subcommittee SC 2, Testing and analysis. This fourth edition cancels and replaces the third edition (ISO 6502:1999), of which it constitutes a mino
17、r revision. The references have been updated.iv ISO 2016 All rights reservedBS ISO 6502:2016ISO 6502:2016(E) Introduction In this International Standard, it became clear that a number of different curemeters were available and that significant developments had taken place, especially with the rotorl
18、ess types. Rather than specify individual rotorless instruments, possibly restricting future developments, it was felt that a more general document was required. Accordingly, it was decided to provide guidance and assistance in the design and use of curemeters generally. ISO 2016 All rights reserved
19、 vBS ISO 6502:2016BS ISO 6502:2016Rubber Guide to the use of curemeters WARNING Persons using this International Standard should be familiar with normal laboratory practice. This International Standard does not purport to address all of the safety problems, if any, associated with its use. It is the
20、 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 provides guidance on the determination of vulcanization characteristics of rubber compounds by means of curemeters. 2
21、 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendm
22、ents) applies. ISO 1382, Rubber Vocabulary 3 T erms a nd definiti ons For the purposes of this document, the terms and definitions given in ISO 1382 and the following apply. 3.1 oscillating-disc curemeter ODC curemeter consisting of a biconical disc oscillated within a temperature-controlled die cav
23、ity containing the test piece Note 1 to entry: An oscillating-disc curemeter is also known as an oscillating disc rheometer (ODR). 3.2 rotorless curemeter RCM curemeter consisting of two dies forming a temperature-controlled cavity, one of which is moved relative to the other to apply a stress or st
24、rain to the test piece Note 1 to entry: A rotorless curemeter is also known as a moving die rheometer (MDR). Note 2 to entry: Types of rotorless curemeter are listed in Clause 5 and illustrated in Figure 3 to Figure 7. 3.3 marching-modulus cure type of vulcanization during which the modulus does not
25、 reach a maximum value but, after a rapid rise, continues to rise slowly at the vulcanization temperature 3.4 vulcanization characteristics characteristics which may be taken from a vulcanization curve Note 1 to entry: See Figure 1. Note 2 to entry: More explanations are given in Clause 4. INTERNATI
26、ONAL ST ANDARD ISO 6502:2016(E) ISO 2016 All rights reserved 1BS ISO 6502:2016ISO 6502:2016(E) 3.5 stiffness measure of the resistance offered by rubber to deformation Note 1 to entry: Force and torque have not been defined since they have a generally accepted scientific meaning. 4 Basic principles
27、The properties of a rubber compound change during the course of vulcanization, and the vulcanization characteristics can be determined by measuring properties as a function of time and temperature. Vulcanization characteristics are most commonly determined using instruments known as curemeters in wh
28、ich a cyclic stress or strain is applied to a test piece and the associated strain or force is measured. Normally, the test is carried out at a predetermined constant temperature and the measure of stiffness recorded continuously as a function of time. The stiffness of the rubber increases as vulcan
29、ization proceeds. Vulcanization is complete when the recorded stiffness rises to a plateau value or to a maximum and then declines (see Figure 1). In the latter case, the decrease in stiffness is caused by reversion. In cases where the recorded stiffness continues to rise (marching-modulus cure), vu
30、lcanization is deemed to be complete after a specified time. The time required to obtain a vulcanization curve is a function of the test temperature and the characteristics of the rubber compound. Curves analogous to Figure 1 are obtained for a curemeter in which strain is measured. The following vu
31、lcanization characteristics can be taken from the measure of stiffness against time curve (Figure 1): Minimum force or torque F Lor M L Force or torque at a specified time t F tor M t Scorch time (time to incipient cure) t sx Time to a percentage y of full cure from minimum force or torque t c (y) P
32、lateau force or torque F HFor M HF Maximum force or torque (reverting cure) F HRor M HR Force or torque value attained after a specified time (marching-modulus cure) F Hor M H The minimum force or torque F Lor M Lcharacterizes the stiffness of the unvulcanized compound at the curing temperature. The
33、 scorch time (time to incipient cure) t sxis a measure of the processing safety of the compound. The time t c (y) and the corresponding forces or torques give information on the progress of cure. The optimum cure is often taken as t c (90). The highest force or torque is a measure of the stiffness o
34、f the vulcanized rubber at the curing temperature. NOTE The term F denotes force and the term M denotes torque.2 ISO 2016 All rights reservedBS ISO 6502:2016ISO 6502:2016(E) 12 34 5 Shear force torque, F or M F L or M L F t or M t F HR or M HR t a) Vulcanization curve F or M = f(t) F or M x t sx t c
35、 (10) t c (50) t c (90) t HF = F F HF = M M L = F F HF = M M , y = 100 or y = 10 y = 50 y = 90 , y = 100 or b) Method of evaluation Key 1 sinusoidal curve 2 envelope curve 3 vulcanization curve with steady increase to F Hor M Hat time t eat end of test (marching-modulus cure) 4 vulcanization curve w
36、ith plateau at F HFor M HF(plateau cure) 5 vulcanization curve with maximum F HRor M HRat time t max(reverting cure) Figure 1 Typical vulcanization curve and method of evaluation ISO 2016 All rights reserved 3BS ISO 6502:2016ISO 6502:2016(E) 5 Types of curemeter Three types of curemeters have found
37、widespread use: oscillating-disc; reciprocating-paddle; rotorless. The reciprocating-paddle type was popular, but is now much less used and is not considered further in this International Standard. Rotorless curemeters can be subdivided into three forms: reciprocating (linear strain); oscillating (t
38、orsion) unsealed cavity; oscillating (torsion) sealed cavity. Oscillating types may have a biconical die, a flat-plate die or be of top-hat section. Other geometries are possible, for example with a vibrating probe or needle. The oscillating-disc curemeter has for many years been the most widely use
39、d type of instrument, recently the rotorless type of curemeter has increased greatly in popularity. The principal advantages of the rotorless type are that the specified temperature is reached in a shorter time after insertion of the test piece into the die cavity and there is better temperature dis
40、tribution in the test piece (see Annex A). 6 Apparatus 6.1 General A curemeter consists of two heated dies with means of closing them under a specified force to form a die cavity containing the test piece, a means of oscillating a rotor within the cavity, or alternatively oscillating or reciprocatin
41、g one of the dies relative to the other, and a means of measuring and recording the force or torque required to produce the relative movement, or the movement produced by a given applied force or torque. In addition, with sealed rotorless torsion systems, reaction torque on the stationary die opposi
42、te the moving die may be measured. The general arrangements for oscillating-disc and rotorless curemeters are shown in Figure 2 to Figure 7. 6.2 Die cavity The dies should be manufactured from a non-deforming material. The surface of the dies should minimize the effect of contamination and be hard s
43、o as to prevent wear. A minimum Rockwell hardness of 50 HRC, or equivalent, is recommended. The tolerances necessary on the dimensions of the dies will depend on the particular design, but as a general guide the dimensions of the cavity should be controlled to 0,2 %. The top and bottom surfaces of t
44、he cavity should have a pattern of grooves of dimensions sufficient to prevent slippage of the rubber test piece. Holes should be provided in both the upper and lower dies to accommodate temperature sensors. The positions of the sensors relative to the cavity should be controlled to ensure reproduci
45、ble response. In the case of oscillating-disc instruments, one die requires a central hole to allow insertion of the die stem. A seal of suitable low, constant friction should be provided in this hole to prevent material leaking from the cavity.4 ISO 2016 All rights reservedBS ISO 6502:2016ISO 6502:
46、2016(E) Suitable means should be employed by design of dies or otherwise to apply pressure to the test piece throughout the test to minimize slippage between the disc and the rubber. A positive pressure is also important to exclude air which might affect the cure of, for example, peroxide-cured rubb
47、ers and to prevent any tendency for the rubber to become porous. The dimensions of the die cavity may be checked by measuring the dimensions of the vulcanized test piece. For biconical-die rotorless curemeters, particular attention should be paid to the thin central portion, the thickness of which d
48、epends on the die gap. For oscillating-disc curemeters, the vulcanized test piece should be cut in half and checked to see that it is symmetrical. Any asymmetry indicates that the rotor height has been set incorrectly. The dimensions of the cavity and of the vulcanized test piece will not be identic
49、al because of the effect of mould shrinkage. 6.3 Die closure The dies are closed and held closed during the test by, for example, a pneumatic cylinder. A force of 11 kN 0,5 kN is recommended for oscillating-disc instruments with a mating-surface area between the dies of approximately 1 400 mm 2 . In unsealed rotorless instruments, the dies are not completely closed but a small clearance is left which should be between 0,05 mm and 0,2 mm. For sealed cavities, no gap should exist at the edges of the die cavity. The mi
