1、March 2008DEUTSCHE NORM English price group 8No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 81.080!$MP|“1424589www.di
2、n.deDDIN EN 993-11Methods of test for dense shaped refractory products Part 11: Determination of resistance to thermal shockEnglish version of DIN EN 993-11:2008-03Prfverfahren fr dichte geformte feuerfeste Erzeugnisse Teil 11: Bestimmung der TemperaturwechselbestndigkeitEnglische Fassung DIN EN 993
3、11:2008-03SupersedesDIN CEN/TS 993-11:2003-11www.beuth.deDocument comprises 13 pagesDIN EN 993-11:2008-03 2 National foreword This standard has been prepared by Technical Committee CEN/TC 187 “Refractory products and materials” (Secretariat: BSI, United Kingdom). The responsible German body involve
4、d in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Technical Committee NA 062-02-57 AA Ungeformte, dichte geformte und wrmedmmende feuerfeste Erzeugnisse und Werkstoffe. Amendments This standard differs from DIN CEN/TS 993-11:2003-11 as follows: a) S
5、ubclause 7.1.3 relating to the heating capacity of the furnace has been deleted. b) Clause 9 “Test report” has been revised. c) The standard has been editorially revised. Previous editions DIN 51068-2: 1980-05 DIN V ENV 993-11: 1997-11 DIN CEN/TS 993-11: 2003-11 EUROPEAN STANDARD NORME EUROPENNE EUR
6、OPISCHE NORM EN 993-11 December 2007 ICS 81.080 Supersedes CEN/TS 993-11:2003 English Version Methods of test for dense shaped refractory products - Part 11: Determination of resistance to thermal shock Mthodes dessai pour produits rfractaires faonns denses - Partie 11: Dtermination de la rsistance
7、au choc thermique Prfverfahren fr dichte geformte feuerfeste Erzeugnisse - Teil 11: Bestimmung der TemperaturwechselbestndigkeitThis European Standard was approved by CEN on 15 November 2007. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for
8、 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 Management Centre or to any CEN member. This European Standard exists in three officia
9、l 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 Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, B
10、elgium, 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. EUROPEAN COMMITTEE F
11、OR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 993-11:2007: EEN 993-11:2007 (E) 2 Content
12、s Page Foreword3 Introduction .5 1 Scope 6 2 Normative references 6 3 Terms and definitions .6 4 Principle6 4.1 Method A.6 4.2 Method B.6 5 Apparatus .7 6 Test pieces .7 6.1 Number of test pieces .7 6.2 Preparation of test pieces.7 7 Procedure .8 7.1 Heating8 7.2 Cooling8 7.3 Measurement8 8 Expressi
13、on of results 9 8.1 Method A.9 8.2 Method B.9 9 Test report 9 Bibliography 11 DIN EN 993-11:2008-03 EN 993-11:2007 (E) 3 Foreword This document (EN 993-11:2007) has been prepared by Technical Committee CEN/TC 187 “Refractory products and materials”, the secretariat of which is held by BSI. This Euro
14、pean Standard shall be given the status of a national standard, either by publication 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. This document supersedes CEN/TS 993-11:2003. EN 993 Methods of t
15、est for dense shaped refractory products consists of 20 Parts: Part 1: Determination of bulk density, apparent porosity and true porosity Part 2: Determination of true density Part 3: Test methods for carbon-containing refractories Part 4: Determination of permeability to gases Part 5: Determination
16、 of cold crushing strength Part 6: Determination of modulus of rupture at ambient temperature Part 7: Determination of modulus of rupture at elevated temperatures Part 8: Determination of refractoriness-under-load Part 9: Determination of creep in compression Part 10: Determination of permanent chan
17、ge in dimensions on heating Part 11: Determination of resistance to thermal shock Part 12: Determination of pyrometric cone equivalent (refractoriness) Part 13: Specification for pyrometric reference cones for laboratory use Part 14: Determination of thermal conductivity by the hot-wire (cross-array
18、) method Part 15: Determination of thermal conductivity by the hot-wire (parallel) method Part 16: Determination of resistance to sulfuric acid Part 17: Determination of bulk density of granular materials by the mercury method with vacuum Part 18: Determination of bulk density of granular materials
19、by the water method with vacuum Part 19: Determination of thermal expansion by a differential method Part 20: Determination of resistance to abrasion at ambient temperature DIN EN 993-11:2008-03 EN 993-11:2007 (E) 4 According to the CEN/CENELEC Internal Regulations, the national standards organizati
20、ons of the following countries are bound to implement this European Standard: 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
21、 Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. DIN EN 993-11:2008-03 EN 993-11:2007 (E) 5 Introduction Thermal shock of refractory materials used in furnaces is influenced by three main factors: brick dimensions; heating/cooling conditions; material properties. Thermal shoc
22、k tests are usually intended to test material properties. This is done by standardizing brick dimensions and heating conditions through which a relative order of the quality of different types of bricks can be established. However, in case of thermal shock, this can lead to complications in the fiel
23、d of engineering. The major complication is that, depending on the type of heating conditions, various material properties are involved. This can be best illustrated on the basis of thermal stress parameters, which are a measure for critical crack initiation. Table 1 Type of heating condition Hot fa
24、ce condition Stress parameter Example sudden temperature jump / filling of metallurgical vessels constant heat flow into brick . / Furnace preheating constant heating rate /(. cp) . / Controlled preheating where maximum allowable deformation; coefficient of expansion; thermal conductivity; bulk dens
25、ity; cpspecific heat. DIN EN 993-11:2008-03 EN 993-11:2007 (E) 6 1 Scope This European Standard describes two alternative methods for determining the resistance to thermal shock of dense shaped refractory materials by an air quenching method, which proved to give the most reliable results when compa
26、red with the behaviour of refractories in furnace linings. Method B can also be applied to unshaped refractory 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 undate
27、d references, the latest edition of the referenced document (including any amendments) applies. EN 993-6, Methods of test for dense shaped refractory products - Part 6: Determination of modulus of rupture at ambient temperature 3 Terms and definitions For the purposes of this European Standard, the
28、following terms and definitions apply. 3.1 thermal-shock resistance resistance of refractory shapes to damage caused by sudden temperature changes between 950 C and room temperature caused by air blowing 3.2 measure of thermal-shock resistance for method A the number of quench cycles withstood under
29、 the test conditions, and for method B the residual cold modulus of rupture (MOR) and residual sonic velocity after 5 quench cycles under the conditions of the test 4 Principle 4.1 Method A The test piece is homogeneously heated to 950 C in an electric furnace then removed, placed on a steel plate a
30、nd exposed to blowing air. After quenching, the test piece is subjected to a stress of 0,3 MPa in a bending machine. This cycle is repeated until failure of the test piece occurs. The resistance to thermal shock is defined by the number of cycles withstood by the test piece before breaking. 4.2 Meth
31、od B The test piece is homogeneously heated to 950 C in an electric furnace then removed, placed on a steel plate and exposed to blowing air. After quenching this is repeated 4 times. After cooling down, the residual cold MOR and the residual sonic velocity are determined. The resistance to thermal
32、shock is defined by the percentage residual MOR and residual sonic velocity related to the MOR and sonic velocity of non-quenched test pieces. DIN EN 993-11:2008-03 EN 993-11:2007 (E) 7 NOTE Sonic resonance frequency can also be measured but can give different results. For both method A and method B
33、 other quenching temperatures may be agreed upon by the parties concerned and shall be noted in the test report. 5 Apparatus 5.1 Electrically heated furnace, capable of maintaining a temperature of 950 C 25 C. 5.2 Thermocouple, for use at temperatures in excess of 1 000 C. 5.3 Drying oven. 5.4 Heat
34、ing cabinet, for preheating at 250 C to 300 C. 5.5 Blowing device, with a 8 mm diameter nozzle of 5 mm length. 5.6 Equipment for measuring the cold MOR in accordance with EN 993-6. 5.7 Steel plate, 400 mm x 250 mm x 20 mm, with pins to locate the test piece under the air-blast; depending on the dime
35、nsions of the test-piece, the pins are located in such a manner that the air jet blows at the intersection of the diagonals of the test-piece on cooling. 5.8 Equipment for measuring the sonic velocity NOTE Equipment for measuring the sonic velocity in refractories is commercially available and shoul
36、d be used in accordance with the manufacturers instructions. 5.9 Insulated iron tongs for handling the test piece after heating 6 Test pieces 6.1 Number of test pieces 6.1.1 Method A Unless a different number of test pieces has been agreed upon, one test piece shall be taken from each item. 6.1.2 Me
37、thod B Unless a different number of test pieces has been agreed upon, four test pieces shall be used. Two test pieces are used for the determination of the cold MOR before testing, MORn. The other two test pieces are used for the thermal shock test. For all four test pieces, determine the sonic velo
38、city, SVn, axially in length of the test pieces before testing. 6.2 Preparation of test pieces 6.2.1 Shape For method A the test pieces shall have the dimensions of a quarter-standard brick, i.e. 114 mm x 64 mm x 64 mm. For method B the test pieces shall have the dimensions of a half-standard brick,
39、 i.e. 230 mm x 64 mm x 54 mm. DIN EN 993-11:2008-03 EN 993-11:2007 (E) 8 They shall be sawn or ground from bricks. NOTE The use of other shapes may be agreed by the parties, but the results will not be directly comparable with those obtained using the test pieces stated above. The test pieces shall
40、be prepared with care so that the brick texture is not damaged. The location within the bricks from which the test pieces are to be taken shall be agreed upon. 6.2.2 Drying of the test pieces Dry the test pieces at 110 C 5 C to constant mass. Constant mass is obtained when the change in mass after t
41、wo successive periods of 1 h drying, is not more than 0,1 %. Protect the test pieces from moisture before testing. 7 Procedure 7.1 Heating 7.1.1 Place the test pieces on one of their long faces, i.e. for method B on a 230 mm x 64 mm face, into a heating cabinet pre-heated to 250 C and 300 C and keep
42、 them at this temperature for at least 4 h. 7.1.2 Put the test pieces into the furnace at 950 C 25 C. The temperature of the furnace is measured with a thermocouple positioned over the centre of the basal area of the furnace approximately 20 mm above the test pieces. Immediately after the door of th
43、e furnace has been closed, the temperature should not be less than 750 C. Keep the samples in the furnace until they are evenly heated. 7.2 Cooling Remove a test piece as quickly as possible from the furnace using insulated iron tongs and place its long face on the steel plate, taking care that the
44、nozzle of the air-blowing device and the centre of the upper face are aligned, with the help of the locating pins. The distance between the nozzle and the test piece shall be 100 mm. Blow compressed air on the test piece for five minutes, ensuring that the pressure immediately before the nozzle is c
45、onstant and equal to 0,1 MPa 0,01 MPa. Be sure that the compressed air is at room temperature and does not contain moisture likely to concentrate in droplets. Always expose the same face of the test piece to the blast. NOTE If conditions remain in accordance with 7.1 and 7.2, more than one test-piec
46、e can be simultaneously or successively tested. Should it be necessary to interrupt the test, the test pieces shall be maintained in the heating cabinet at 250 C to 300 C after the last quenching. When testing is resumed, the test pieces shall be placed immediately in the furnace at 950 C 25 C. 7.3
47、Measurement 7.3.1 Method A 7.3.1.1 After quenching, the test piece is submitted to a bending strength of 0,3 MPa 0,05 MPa gradually and without shock. 7.3.1.2 The distance between supports shall be 100 mm. The thrust column and the supports shall have a radius of 5 mm. NOTE If the test piece breaks,
48、 the test is completed. DIN EN 993-11:2008-03 EN 993-11:2007 (E) 9 7.3.1.3 If the test piece withstands the bending stress, place it again into the furnace at 950 C and start the same cycle. Continue the test until the test piece breaks in the bending test or breaks up into two or more pieces under
49、the cooling blast. The test shall be ended when the test piece has withstood 30 quenchings. 7.3.2 Method B 7.3.2.1 General After 5 quenchings, the following measurements and determinations have to be applied: 7.3.2.2 After cooling down to ambient temperature, again measure the sonic velocity, SVquenched. NOTE It can be interesting to study the behaviour of the sonic velocity in function of cycles. In this case the test pieces are cooled down to ambient temperatures after each cycle before the meas
