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1、BRITISH STANDARD BS 3473-1: 1991 ISO 695:1991 Chemical resistance of glass used in the production of laboratory glassware Part 1: Method for determination of resistance of glass to attack by a boiling aqueous solution of mixed alkali Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:11:03 GM
2、T+00:00 2006, Uncontrolled Copy, (c) BSI BS 3473-1:1991 This British Standard, having been prepared under the direction of the Laboratory Apparatus Standards Policy Committee, was published under the authority of the Standards Board and comes into effect on 31 July 1991 BSI 10-1999 First published 1
3、962 Second edition as Part 1, October 1982 Third edition July 1985 Fourth edition July 1991 The following BSI references relate to the work on this standard: Committee reference LBC/8 Draft for comment 89/56195 DC ISBN 0 580 19894 4 Committees responsible for this British Standard The preparation of
4、 this British Standard was entrusted by the Laboratory Apparatus Standards Policy Committee (LBC/-) to Technical Committee LBC/8, upon which the following bodies were represented: British Glass Manufacturers Confederation Society of Glass Technology Amendments issued since publication Amd. No.DateCo
5、mments Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:11:03 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3473-1:1991 BSI 10-1999i Contents Page Committees responsibleInside front cover National forewordii 1Scope1 2Normative references1 3Principle1 4Reagents1 5Apparatus1 6Preparation and
6、number of samples2 7Procedure2 8Expression of results3 9Precision3 10Test report3 Figure 1 Examples of suitable test vessels with a hemispherical and a flat base4 Table 1 Limit values in the alkali resistance test3 Publication(s) referred toInside back cover Licensed Copy: sheffieldun sheffieldun, n
7、a, Wed Nov 29 08:11:03 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3473-1:1991 ii BSI 10-1999 National foreword This Part of BS 3473 has been prepared under the direction of the Laboratory Apparatus Standards Policy Committee. It supersedes BS 3473-1:1985, which is withdrawn, and is identical with
8、 ISO 695:1991 “Glass Resistance to attack by a boiling aqueous solution of mixed alkali Method of test and classification”, published by the International Organization for Standardization (ISO). It has been prepared by subcommittee 5 of Technical Committee 48, Laboratory glassware and related appara
9、tus, with the active participation and approval of the UK. BS 3473 was first published in 1962 as a single publication which described procedures for determining the resistance of glass used in the production of laboratory glassware to attack by a boiling aqueous solution of mixed alkali, and to wat
10、er at 100 C and 121 C. To facilitate alignment with corresponding International Standards, the revision of BS 3473 was begun in 1981 with the publication of the first three Parts of what was then intended to be a six-Part standard. Part 6, which was to deal with classification, will not now be issue
11、d as it has been agreed internationally to include classification in the individual test methods. BS 3473 currently consists of the following Parts. Part 1: Method for determination of resistance of glass to attack by a boiling aqueous solution of mixed alkali; (Identical with ISO 695:1991) Part 2:
12、Method for determination of hydrolytic resistance of glass grains at 98 C; (Identical with ISO 719:1985) Part 3: Method for determination of hydrolytic resistance of glass grains at 121 C; (Identical with ISO 720:1985) Part 4: Methods for determination of hydrolytic resistance of the interior surfac
13、es of glass containers; Section 4.1 Determination by titration method and classification; (Identical with ISO 4802-1:1988) Section 4.2 Determination by flame photometry and classification; (Identical with ISO 4802-2:1988) Part 5: Method for determination of resistance of glass to attack by 6 mol/L h
14、ydrochloric acid at 100 C; (Identical with ISO 1776:1985) The procedures described in BS 3473 are recommended as being capable of yielding consistent results in the hands of independent workers in different laboratories and offer a means of assessing the chemical resistance of glass used in the prod
15、uction of laboratory ware when tested by the specified procedure. Because the term “laboratory glassware” covers a wide variety of articles to serve many different purposes and the glass types used include both borosilicate and soda-lime-silica glass, methods of test are required which are widely ap
16、plicable. Tests of fractured surfaces, such as the grain test described in Parts 2 and 3 give an assessment of the chemical behaviour of the body of the glass and can be applied to articles of laboratory glassware because they are usually used many times. Such tests have a more limited value for ass
17、essing the chemical resistance of glass articles which are to be used once only because the resistance depends more on the condition of the surface than on the body of the glass; BS 3473-4 relates to such applications. Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:11:03 GMT+00:00 2006, U
18、ncontrolled Copy, (c) BSI BS 3473-1:1991 BSI 10-1999 iii It should be realized that whilst these procedures can be used to assess the behaviour of glass under the stated conditions, and thus to select glasses for general laboratory purposes, they can only reveal or measure limited aspects of chemica
19、l behaviour. Where articles are designed for a specific purpose, it is essential that the performance of the glass should be evaluated in terms of precise service requirements by using simulative or functional tests. This revision introduces improvements to the test procedure and precision data deri
20、ved from an inter-laboratory study. A related British Standard to ISO 683-13:1986 is BS 970 “Specification for wrought steels for mechanical and allied engineering purposes” Part 1:1988 “General inspection and testing procedures and specific requirements for carbon, carbon manganese, alloy and stain
21、less steels.” CAUTION. Attention is drawn to the Health and Safety at Work etc. Act, 1974, and the need for ensuring that the method of test specified in this standard is carried out with suitable precautions. The procedure described in this standard method is intended to be carried out by qualified
22、 chemists or other suitably trained and/or supervised personnel. Normal safety precautions should be observed throughout the use of the method. Particular attention is drawn to the need to wear suitable eye-protectors during the preparation and handling of glass fragments; see BS 2092 “Specification
23、 for eye-protectors for industrial and non-industrial uses” for details of suitable types. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not
24、of itself confer immunity from legal obligations. Cross-references International Standard Corresponding British Standard BS 3473 Chemical resistance of glass used in the production of laboratory glassware ISO 719:1985 Part 2:1987 Method for determination of hydrolytic resistance of glass grains at 9
25、8 C (Identical) ISO 720:1985 Part 3:1987 Method for determination of hydrolytic resistance of glass grains at 121 C (Identical) ISO 3693:1987 BS 3978:1987 Specification for water for laboratory use (Identical) ISO 3819:1985 BS 6523:1984 Specification for glass beakers for laboratory use (Technically
26、 equivalent) ISO 4799:1978 BS 5922:1980 Specification for glass condensers for laboratory use (Identical) Summary of pages This document comprises a front cover, an inside front cover, pages i to iv, pages 1 to 4, an inside back cover and a back cover. This standard has been updated (see copyright d
27、ate) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:11:03 GMT+00:00 2006, Uncontrolled Copy, (c) BSI iv blank Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:11:03
28、GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3473-1:1991 BSI 10-19991 1 Scope This International Standard specifies a) a method for determining the resistance of glass to attack by a boiling aqueous solution of sodium carbonate and sodium hydroxide. The resistance is measured inversely by the loss
29、in mass per unit surface area of the glass; b) a classification of glass according to the alkali resistance determined by the method of this International Standard. NOTE 1The method of test according to this International Standard is also applicable for determining the alkali resistance of glass cer
30、amics. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based
31、on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 683-13:1986, Heat-treatable steels, alloy steels and free-cutt
32、ing steels Part 13: Wrought stainless steels. ISO 719:1985, Glass Hydrolytic resistance of glass grains at 98 C Method of test and classification. ISO 720:1985, Glass Hydrolytic resistance of glass grains at 121 C Method of test and classification. ISO 3696:1987, Water for analytical laboratory use
33、Specification and test methods. ISO 3819:1985, Laboratory glassware Beakers. ISO 4799:1978, Laboratory glassware Condensers. 3 Principle 3.1 Immersion of two sample pieces, each having a total surface area of 10 cm2 to 15 cm2 in a boiling aqueous solution of equal volumes of sodium carbonate, c(Na2C
34、O3) = 0,5 mol/l, and sodium hydroxide c(NaOH) = 1 mol/l, for 3 h. Calculation of the loss in mass per unit surface area of the glass. 4 Reagents During the test, unless otherwise stated, use only reagents of recognized analytical grade and only distilled water or water of equivalent purity (grade 3
35、water complying with the requirements of ISO 3696). 4.1 Acetone, CH3COCH3. 4.2 Hydrochloric acid, solution, c(HCl) 1 mol/l. 4.3 Hydrochloric acid, solution, c(HCl) 2 mol/l. 4.4 Hydrofluoric acid, c(HF) 22 mol/l (i.e. 400 g HF/l solution). 4.5 Sodium carbonate, solution, c(Na2CO3) = 0,5 mol/l 0,01 mo
36、l/l, freshly prepared for each test. 4.6 Sodium hydroxide, solution, c(NaOH) = 1 mol/l 0,02 mol/l, freshly prepared for each test. 5 Apparatus 5.1 Test vessel, of pure silver, alkali-resistant silver alloy or stainless steel type 151) complying with the requirements of ISO 683-13. A recommended test
37、 vessel, as shown in Figure 1, is cylindrical with a hemispherical or flat base and has a close-fitting lid. The lid has a wide neck and is equipped on the internal surface with four hooks from which to suspend the sample pieces. A gasket, made of a material which remains inert under the test condit
38、ions, shall be used to form a seal between the lid and the body of the test vessel. 5.2 Condenser, of the Allihn or Liebig-West type, complying with the requirements of ISO 4799 and made of glass of hydrolytic resistance grain class HGA 1 of ISO 7202) fitted to the neck of the lid through a bung of
39、suitable inert material which has previously been boiled for 60 min in water. 5.3 Balance, accurate to 0,1 mg. 5.4 Desiccator, containing a suitable drying agent. 5.5 Measuring instruments, suitable for measuring lengths and diameters to an accuracy of 1 %. 5.6 Drying oven, suitable for operation at
40、 a temperature of 110 C. 5.7 Beaker, 1 litre capacity, complying with the requirements of ISO 3819. 5.8 Silver wire 5.9 Tongs, tipped, if necessary, with a suitable material, e.g. plastics, silver, platinum. 1) The relevant constituents of steel type 15 are 18 % Cr, 10 % Ni, maximum 0,08 % C and an
41、addition of Ti. 2) Glass of hydrolytic resistance grain class ISO 719-HGB 1 adequately meets the requirements of class HGA 1 of ISO 72O. Licensed Copy: sheffieldun sheffieldun, na, Wed Nov 29 08:11:03 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 3473-1:1991 2 BSI 10-1999 5.10 Heating bath, fitted w
42、ith a thermostat and temperature controller capable of heating and maintaining the bath liquid, e.g. glycerol, at a temperature between 110 C and 112 C. The heating bath shall be supplied with a stirring device or a liquid circulator and be fitted with a lid or a supply of plastics balls to complete
43、ly cover the surface of the bath liquid. It shall be of sufficient capacity to allow each test vessel to be immersed in the bath liquid until the level of the liquid inside the test vessel is level with that in the heating bath and with a distance of about 60 mm all round the test vessel. These cond
44、itions shall also be fulfilled if several test vessels are simultaneously placed in the heating bath. The heating bath shall be supplied with temperature measuring devices, e.g. digital thermometers, to allow the bath liquid temperature to be measured over the range 110 C to 112 C. 6 Preparation and
45、 number of samples 6.1 Glass “as delivered” Cut the sample piece or sample pieces (hereinafter referred to as “sample”) from the glass into easily measurable shapes such as squares, rectangles or, from tubing, open-ended cylinders. Each sample shall have a total surface area, surfaces plus edges, of
46、 between 10 cm2 and 15 cm2. Remove any sharp angles, “hackles” or splinters by polishing the edges or bevelling the corners. Do not firepolish any part of the samples. This concerns only samples where the new cut surface area is not more than 20 % of the total surface area. Otherwise the sample shal
47、l be submitted to the etching procedure according to 6.2 and regarded as glass “as a material”. 6.2 Glass “as a material” Immerse the sample(s) completely in a mixture of 1 volume of hydrofluoric acid (4.4) and 9 volumes of hydrochloric acid (4.3). Allow the samples to stand at ambient temperature f
48、or 10 min. Holding the samples in position, pour out the mixture very carefully. Rinse the sample(s) five times with distilled water (see first paragraph of clause 4). 6.3 Number of samples For each test, both for glass “as delivered” or “as a material”, two samples shall be tested. 7 Procedure 7.1
49、Number of samples in a test vessel When “unknown” glasses are to be examined only two samples shall be tested at the same time. When glasses with a loss in mass per unit surface area not greater than 200 mg/dm2 are to be examined, up to four samples of two different types of glasses may be tested simultaneously. 7.2 Method Measure and calculate the total surface area of each sample, surfaces plus edges, to an accuracy of 2 % and record the value obtained. Wash each sample, using the tongs (5.9) to hold the glass