BS EN 12607-2:2014 BS 2000-460-2:2014 BSI Standards Publication Bitumen and bituminous binders — Determination of the resistance to hardening under influence of heat and air Part 2: TFOT method BS EN 12607-2:2014 BRITISH STANDARD National foreword This British Standard is the UK implementation of EN 12607-2:2014 It supersedes BS EN 12607-2:2007 which is withdrawn The UK participation in its preparation was entrusted to Technical Committee PTI/13, Petroleum Testing and Terminology A list of organizations represented on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 application © The British Standards Institution 2014 Published by BSI Standards Limited 2014 ISBN 978 580 77117 ICS 75.140; 91.100.50 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 Committee on 30 November 2014 BS 2000 Series Energy Institute, under the brand of IP, publishes and sells all Parts of BS 2000, and all BS EN and BS ISO petroleum test methods that would be part of BS 2000, both in its annual publication “IP Standard Test Methods for analysis and testing of petroleum and related products, and British Standard 2000 Parts” and individually Amendments/corrigenda issued since publication Date Text affected EN 12607-2 EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM November 2014 ICS 75.140; 91.100.50 Supersedes EN 12607-2:2007 English Version Bitumen and bituminous binders - Determination of the resistance to hardening under influence of heat and air - Part 2: TFOT method Bitumes et liants bitumineux - Détermination de la résistance au durcissement sous l'effet de la chaleur et de l'air - Partie 2: Méthode TFOT Bitumen und bitumenhaltige Bindemittel - Bestimmung der Beständigkeit gegen Verhärtung unter Einfluss von Wärme und Luft - Teil 2: TFOT-Verfahren This European Standard was approved by CEN on 16 August 2014 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 application to the CEN-CENELEC Management Centre 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 CEN-CENELEC Management Centre has the same status as the official versions CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels © 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members Ref No EN 12607-2:2014 E BS EN 12607-2:2014 EN 12607-2:2014 (E) Contents Page Foreword Scope Normative references Principle 4 Apparatus .5 Sampling 6 Procedure .7 Calculation Expression of results Precision 10 Test report Annex A (informative) Characteristics of thermometers 10 Bibliography 11 BS EN 12607-2:2014 EN 12607-2:2014 (E) Foreword This document (EN 12607-2:2014) has been prepared by Technical Committee CEN/TC 336 “Bituminous binders”, the secretariat of which is held 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 2015 and conflicting national standards shall be withdrawn at the latest by May 2015 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 not be held responsible for identifying any or all such patent rights This document supersedes EN 12607-2:2007 This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association In comparison with EN 12607-2:2007, the following significant changes have been made: — changed/added wording of the Warning in the Scope; — EN 12595, Bitumen and bituminous binders — Determination of kinematic viscosity has been added to Clause 2; — the reference to mercury thermometer has been deleted (see subclause 4.2) and Annex A is informative EN 12607 consists of the following parts under the general title “Bitumen and bituminous binders – Determination of the resistance to hardening under the influence of heat and air”: — Part 1: RTFOT method; — Part 2: TFOT method; — Part 3: RFT method The scope of this standard has been enlarged by adding oxidized bitumens and hard industrial bitumens that are not used for paving applications The reason is to facilitate that EN 13303, Bitumen and bituminous binders – Determination of the loss of mass after heating of industrial bitumen can be replaced in product standards by EN 12607-2 at the next revision of EN 13303 It is to be noted that this – if so decided – will change the property from loss in mass into change in mass in EN 13304, Bitumen and bituminous binders – Framework for specification of oxidized bitumens and in EN 13305, Bitumen and bituminous binders – Framework for specification of hard industrial bitumens According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom BS EN 12607-2:2014 EN 12607-2:2014 (E) Scope This part of EN 12607 specifies a method for measuring the combined effects of heat and air on a film of bitumen or bituminous binder, simulating the hardening which most bituminous binders undergo during mixing in an asphalt mixing plant The method is suitable for other bituminous binders than paving grade bitumen, but the reference temperature might give excessive hardening that does not resemble real conditions during mixing at the plant The method may not represent the hardening that occurs during mixing of warm mix binders Additionally, this part of EN 12607 specifies a method for the determination of the change in mass of oxidized bitumens and hard industrial bitumens after heating The method is used to detect volatile components The method is referred to as TFOT, i.e Thin Film Oven Test WARNING — Use of this European Standard can involve hazardous materials, operations and equipment This European Standard does not purport to address all of the safety problems associated with its use It is the responsibility of the user of this European Standard to identify the hazards and assess the risks involved in performing this test method and to implement sufficient control measures to protect individual operators (and the environment) This includes appropriate safety and health practices and determination of the applicability of regulatory limitations prior to use If there is a likelihood of volatile components being present in a binder, this procedure should not be used It should not be used for cut-back bitumen or bituminous emulsions before these products have been stabilized, e.g in accordance with EN 13074-2 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 amendments) applies EN 58, Bitumen and bituminous binders - Sampling bituminous binders EN 1425, Bitumen and bituminous binders - Characterization of perceptible properties EN 12594, Bitumen and bituminous binders - Preparation of test samples EN 12595, Bitumen and bituminous binders - Determination of kinematic viscosity Principle A film of bituminous binder is heated in an oven at a specified temperature for a given period of time For bituminous binders for paving applications, the effects of heat and air are determined based on the change in mass (expressed as a percentage) and on the change in the bituminous binder's properties such as kinematic viscosity according to EN 12595, before and after the period in the oven For bituminous binders for industrial applications, the combined effects of heat and air and loss of volatiles are determined based on the change in mass (expressed as a percentage) This will be the value from this conditioning method that will be utilized in EN 13304 and EN 13305 as loss in mass (change in sign) NOTE Penetration according to EN 1426 and softening point according to EN 1427 can be measured on harder grades before and after oven treatment at 163 °C BS EN 12607-2:2014 EN 12607-2:2014 (E) Apparatus Usual laboratory apparatus and glassware, together with the following: 4.1 Oven, electrically heated and conforming to the performance requirements indicated in Table for operating temperatures up to 180 °C The oven shall be rectangular with a minimum interior height, width and depth of 330 mm The front door shall be hinged and tightly fitted, and have a clear opening of the same height and width as the interior of the oven The window on the door shall be at least 100 mm by 100 mm, with two sheets of glass separated by an air space The window shall permit an unobstructed view of the interior of the oven so that the control thermometer, located as specified in 6.1 may be read without opening the door NOTE The oven can alternatively be provided with an inner glass door through which the thermometer can be read upon opening the outer door momentarily The oven shall be ventilated by convection currents of air; the oven shall have air inlets and outlets evacuating hot gases meeting the requirements of Table NOTE met These inlets and outlets can be of different size and arrangement provided the requirements in Table are Table — Performance requirements for Thin Film Oven Characteristics Requirements Deviation from a specified test temperature throughout the testing chamber during a 24 h period for the differential between ambient and test temperature, when more than 50 °C, maximum, % of differential Time constant, maximum, s 720 Rate of ventilation of testing chamber, air changes per h, minimum 10 NOTE These performance requirements are extracted from ASTM E145, type IB (gravity convection ventilated oven) The oven shall be provided with a metal circular shelf with a minimum diameter of 250 mm The shelf shall provide a flat surface to support the containers without blocking all air circulation through the shelf when the containers are in place The shelf shall be suspended by a vertical shaft and centred with respect to the horizontal interior of the oven The shelf shall be mechanically driven to rotate at the rate of (5,5 ± 1,0) r/min The shelf shall be vertically located as close to the centre of the oven as allowed by the requirements of 6.1 regarding thermometer placement Minimum size ovens allow the use of two containers Larger ovens, having proportionally larger shelves to accommodate a greater number of containers can be suitable Under no circumstances should more than one shelf, properly centred, be used in an oven 4.2 Temperature measuring device A temperature measuring device (combining sensor and reading unit) shall — have a range from at least 110 °C to 170 °C, — be readable to 0,1 °C or less and, — have an accuracy of 0,5 °C or better BS EN 12607-2:2014 EN 12607-2:2014 (E) Sensors based on platinum resistance thermometers have been found suitable but other principles are also allowed The thermal response time of the sensor shall be comparable with the former used reference (see informative Annex A) The temperature measuring device shall be calibrated regularly A solid stem mercury thermometer (which used to be the former reference thermometer as described in Annex A) is also allowed if national regulations permit its use When measuring and controlling nominally constant temperatures as in this test method, the thermal response time can be rather high (e.g slow response to a change in temperature) Care shall be taken to consider this aspect since low thermal response times of the sensor can indicate greater cyclic variations than the bituminous material in practise 4.3 Container, (in which the sample of bituminous binder is subjected to the test), cylindrical pan (140 ± 1) mm in inside diameter and (9,5 ± 0,5) mm deep with a flat bottom, stainless steel or aluminium, with a thickness of (0,6 ± 0,1) mm to (1,0 ± 0,1) mm NOTE 50 ml of sample in this container will give a film thickness of approximately 3,2 mm NOTE Containers have a tendency to become warped or bent with use Although a small amount of warping does not significantly affect results, it is advisable to eliminate damaged pans 4.4 Balance, accurate to ± 10 mg, readable to mg Sampling 5.1 General Make sure that the laboratory sample is homogeneous and is not contaminated according to EN 1425 Take all necessary safety precautions and ensure that the test sample is representative of the laboratory sample from which it is taken (see EN 58) The laboratory sample shall be taken in accordance with EN 58 5.2 Test sample preparation Prepare the test sample in accordance with EN 12594 Remove a sufficient quantity of the laboratory sample to perform tests to establish the characteristics to be measured on the bituminous binder before and after the RTFOT hardening test If necessary, use a warmed knife and transfer it to a suitable container according to EN 12594 The sample shall be free of water Heat the sample in an oven in its container with a loosely fitted cover to a fluid condition not exceeding 10 °C below the test temperature for the minimum time necessary, to ensure that the sample is completely fluid Homogenize the sample by stirring If special bituminous binders, modified binders or bituminous binders with a high softening point are tested, it may be necessary to prepare the sample at a higher temperature In this case, heat the sample as described above and in accordance with EN 12594 For polymer modified bitumens, the temperature may not exceed 200 °C, irrespective of the softening point 5.3 Initial characteristics Determine the initial characteristics of the bituminous binder using an appropriate test method, according to the grade in question, e.g the kinematic viscosity at 60 °C (EN 12595), ν1 BS EN 12607-2:2014 EN 12607-2:2014 (E) Procedure 6.1 Test conditions Ensure that the oven (4.1) is level so that the shelf rotates on a horizontal plane with a maximum tilt during rotation of not more than 3° from the horizontal Determine the temperature of the oven with the specified thermometer (4.2) in a vertical position at a point equidistant from the centre and the outer edge of the shelf and the bottom of the thermometer bulb approximately mm above the top of the shelf For bituminous binders for paving applications, the reference temperature of the test is (120 ± 1) °C, corresponding to the mixing temperature of soft paving grade bitumens NOTE grades However, it is possible to perform the test at other temperatures, e.g (163 ± 1) °C for harder paving bitumen For bituminous binders for industrial applications, the reference temperature of the test is (163 ± 1) °C 6.2 Determination Weigh separately containers (4.3) to the nearest mg (m0) Pour (50,0 ± 0,5) g of the sample into each of two or more of the containers Allow the samples to cool to room temperature for approximately 30 min, and weigh them separately to the nearest mg (m1) With the oven at the test temperature ± °C, rapidly place the containers with the sample on the circular shelf, close the oven, and commence rotating the shelf Maintain the sample in the oven for h from the time the test temperature reaches °C below the test temperature Ensure that the total time that a sample is in the oven is not more than h 15 At the end of the heating period, remove the samples from the oven Cool to room temperature for approximately 30 min, weigh to the nearest mg (m2), and calculate the change in mass of the bituminous binder in each container Do not test different samples in the same oven at the same time When a complete test cannot be completed on the same day, weigh the residues and store them overnight before reheating After weighing the samples, place them back on the shelf in the oven at the test temperature Close the oven and rotate the shelf for 15 Remove the samples and transfer the material from each pan into a 250 ml container preheated to the test temperature Stir the combined residues thoroughly, heating the container if necessary 6.3 Measurement of properties Measure the properties chosen in 5.3 (e.g the kinematic viscosity of the residue at 60 °C (EN 12595), ν2) within 72 h Avoid reheating the sample more than once NOTE Excessively reheating the sample can influence the test results obtained Calculation Calculate the change in physical properties or characteristics after the hardening procedure as follows: BS EN 12607-2:2014 EN 12607-2:2014 (E) Δν, ratio of kinematic viscosities at 60 °C Δm, percentage of change in mass = = 100 × ν2 ν1 (1) (m2 − m1 ) (m1 − m0 ) (2) where ν1 is the kinematic viscosity of the sample before hardening, in millimetres squared per second; ν2 is the kinematic viscosity of the residue, in millimetres squared per second; m0 is the mass of the empty container, in grams; m1 is the mass of the container with the sample before the test, in grams; m2 is the mass of the container with the sample after the test, in grams Expression of results Express a loss in mass as a negative percentage change and a gain in mass as a positive percentage change The results of the percentage change in mass for two containers are considered valid if the difference of the two measurements is equal to or less than 0,05 % mass fraction absolute Express the percentage change in mass as the average of a minimum valid determinations to the nearest 0,01 % If the value of a physical property is measured on the sample after TFOT, e.g kinematic viscosity, express the ratio of viscosities to the nearest 0,1 Report the values of initial properties and residue properties Precision 9.1 Repeatability The difference between two test results, obtained by the same operator, with the same apparatus, under constant operating conditions on identical test material would, in the long run, in the normal and correct operation of the test method, exceed the values given in Table in only one case in twenty 9.2 Reproducibility The difference between two single and independent results obtained by different operators working in different laboratories on identical test material would, in the long run, in the normal and correct operation of the test method, exceed the values given in Table in only one case in twenty BS EN 12607-2:2014 EN 12607-2:2014 (E) Table — Precision Characteristics Repeatability, r Reproducibility, R ≤ 0,1 % mass fraction absolute 0,02 % mass fraction 0,14 % mass fraction > 0,1 % mass fraction absolute 8,0 % of mean 38 % of mean % of mean 16 % of mean Change in mass TFOT 120 °C a Ratio of dynamic viscosity at 60 °C TFOT 120 °C a Ratio < 1,5 These precision data are not automatically applicable to modified bitumen and industrial bitumen For modified bitumen they should only be used for guidance until criteria data are available a These figures are based on an analysis of data from sixteen laboratories on three samples of soft paving grade bitumens with a viscosity ratio < 1,5 10 Test report The test report shall contain at least the following information: a) type and complete identification of the sample under test; b) reference to this part of EN 12607; c) test temperature; d) results obtained (see Clause 8); e) any deviation, by agreement or otherwise, from the procedure specified; f) date of the test BS EN 12607-2:2014 EN 12607-2:2014 (E) Annex A (informative) Characteristics of thermometers Table A.1 — Characteristics of thermometers Characteristics Units Test temperatures 120 °C 163 °C °C 114 to 130 155 to 170 Subdivision °C 0,5 0,5 Long lines at each °C 1 Numbers at °C 115, 120, 125, 130 155, 160, 165, 170 Maximum scale error °C 0,5 0,5 total total Temperature range Scale marks Immersion Expansion chamber permits heating to °C 200 200 Total length mm 150 to 160 150 to 160 Stem outside diameter mm 5,5 to 7,0 5,5 to 7,0 Bulb length mm 10 to 15 10 to 15 Bulb outside diameter mm 5,0 to stem diameter 5,0 to stem diameter Bottom of bulb to line at °C 114 155 Distance mm 50 to 60 50 to 60 Length of scale mm 40 to 60 40 to 60 mm 30 30 Scale location Maximum distance of contraction chamber to the top NOTE 10 The thermometer ASTM 13C/IP47C has been found suitable for the test temperature at 163 °C BS EN 12607-2:2014 EN 12607-2:2014 (E) Bibliography [1] EN 1426, Bitumen and bituminous binders - Determination of needle penetration [2] EN 1427, Bitumen and bituminous binders - Determination of the softening point - Ring and Ball method [3] EN 13074-2, Bitumen and bituminous binders - Recovery of binder from bituminous emulsion or cutback or fluxed bituminous binders - Part 2: Stabilisation after recovery by evaporation [4] EN 13304, Bitumen and bituminous binders - Framework for specification of oxidised bitumens [5] EN 13305, Bitumen and bituminous binders - Framework for specification of hard industrial bitumens [6] ASTM E145-94 (2001), Standard Specifications for Gravity Convection and Forced-Ventilation Oven [7] ASTM D1754-97 (2002), Standard Test Method for Effect of Heat and Air on Asphaltic Materials (ThinFilm Oven Test) 11 This page deliberately left blank This page deliberately left blank NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW British Standards Institution (BSI) BSI is the national body responsible for preparing British Standards and other standards-related publications, information and services BSI is incorporated by Royal Charter British Standards and other standardization products are published by BSI Standards Limited About us Revisions We bring together business, industry, government, consumers, innovators and others to shape their combined experience and expertise into standards -based solutions Our British Standards and other publications are updated by amendment or revision The knowledge embodied in our standards has been carefully assembled in a dependable format and refined through our open consultation process Organizations of all sizes and across all sectors choose standards to help them achieve their goals Information on standards We can provide you with the knowledge that your organization needs to succeed Find out more about British Standards by visiting our website at bsigroup.com/standards or contacting our Customer Services team or Knowledge Centre Buying standards You can buy and download PDF versions of BSI publications, including British and adopted European and international standards, through our website at bsigroup.com/shop, where hard copies can also be purchased If you need international and foreign standards from other Standards Development Organizations, hard copies can be ordered from our Customer Services team Subscriptions Our range of subscription services are designed to make using standards easier for you For further information on our subscription products go to bsigroup.com/subscriptions With British Standards Online (BSOL) you’ll have instant access to over 55,000 British and adopted European and international standards from your desktop It’s available 24/7 and is refreshed daily so you’ll always be up to date You can keep in touch with standards developments and receive substantial discounts on the purchase price of standards, both in single copy and subscription format, by becoming a BSI Subscribing Member PLUS is an updating service exclusive to BSI Subscribing Members You will automatically receive the latest hard copy of your standards when they’re revised or replaced To find out more about becoming a BSI Subscribing Member and the benefits of membership, please visit bsigroup.com/shop With a Multi-User Network Licence (MUNL) you are able to host standards publications on your intranet Licences can cover as few or as many users as you wish With updates supplied as soon as they’re available, you can be sure your documentation is current For further information, email bsmusales@bsigroup.com BSI Group Headquarters 389 Chiswick High Road London W4 4AL UK We continually improve the quality of our products and services to benefit your business If you find an inaccuracy or ambiguity within a British Standard or other BSI publication please inform the Knowledge Centre Copyright All the data, software and documentation set out in all British Standards and other BSI publications are the property of and copyrighted by BSI, or some person or entity that owns copyright in the information used (such as the international standardization bodies) and has formally licensed such information to BSI for commercial publication and use Except as permitted under the Copyright, Designs and Patents Act 1988 no extract may be reproduced, stored in a retrieval system or transmitted in any form or by any means – electronic, photocopying, recording or otherwise – without prior written permission from BSI Details and advice can be obtained from the Copyright & Licensing Department Useful Contacts: Customer Services Tel: +44 845 086 9001 Email (orders): orders@bsigroup.com Email (enquiries): cservices@bsigroup.com Subscriptions Tel: +44 845 086 9001 Email: subscriptions@bsigroup.com Knowledge Centre Tel: +44 20 8996 7004 Email: knowledgecentre@bsigroup.com Copyright & Licensing Tel: +44 20 8996 7070 Email: copyright@bsigroup.com