《BS-684-1.7-1976.pdf》由会员分享，可在线阅读，更多相关《BS-684-1.7-1976.pdf（8页珍藏版）》请在三一文库上搜索。
1、BRITISH STANDARD CONFIRMED APRIL 1993 BS 684-1.7: 1976 Methods of analysis of Fats and fatty oils Part 1: Physical methods Section 1.7: Determination of surface-drying time IMPORTANT NOTE. It is essential that this Section be read in conjunction with the information in the “General introduction” to
2、BS 684, which is published separately. UDC 665.1.014:543:667.612.82 Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 13:15:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 684-1.7:1976 This British Standard, having been prepared under the direction of the Oils and Fats Standards Committee, was
3、 published under the authority of the Executive Board on 29 October 1976 BSI 11-1999 The following BSI references relate to the work on this standard: Committee reference OFC/24 Draft for comment 74/50396 DC ISBN 0 580 09135 X A British Standard does not purport to include all the necessary provisio
4、ns of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 and 2 and a
5、 back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No.Date of issueComments Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06
6、 13:15:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 684-1.7:1976 BSI 11-1999i Contents Page 1Scope1 2References1 3Definitions1 4Principle1 5Apparatus1 6Sampling and preparation of sample for analysis1 7Procedure1 8Expression of results2 9Test report2 Licensed Copy: sheffieldun sheffieldun, na, W
7、ed Dec 06 13:15:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ii blank Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 13:15:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 684-1.7:1976 BSI 11-19991 1 Scope This Section describes a method for determining the surface-drying characteristics of
8、 a film of oil and is similar to that described in BS 3900-C2. The method may be carried out either as a “go/no go” test by determining the surface-drying state after a specified time to assess compliance with a particular requirement, or by determining the surface-drying state at suitable intervals
9、 until the surface-drying time is obtained. 2 References The following standards publications are referred to in this Section: BS 245, White spirit. BS 410, Test sieves. BS 458, Xylenes. BS 1796, Methods for the use of British Standard fine-mesh test sieves. BS 3900, Methods of test for paints Part
10、C2: Surface-drying time (ballotini method). 3 Definitions For the purposes of this Section of BS 684 the following definitions apply. 3.1 surface-drying state general term describing the state of the surface of a film of oil, i.e. whether “surface-dry” or not 3.2 surface-dry surface-drying state of
11、a film of oil when ballotini can be lightly brushed away without damaging the surface of the film 3.3 surface-drying time period of time between that at which a film of oil is applied to a prepared test panel, and that at which the film is assessed as just surface-dry by the procedure described in c
12、lause 7 4 Principle Ballotini are poured on the film under specified conditions, then brushed away and the film examined visually. 5 Apparatus The following items of apparatus are required (see also BS 684: General introduction). 5.1 Test panel, of polished plate glass approximately 100 mm 150 mm. 5
13、.2 Ballotini (transparent solid glass spheres), graded so that none passes a sieve of nominal aperture 125 4m, all pass a sieve of nominal aperture 335 4m, and at least 75 % (m/m) pass a sieve of nominal aperture 250 4m but are retained on a sieve of nominal aperture 180 4m. (The test sieves used sh
14、all comply with BS 410 and the testing shall be carried out in accordance with BS 1796.) 5.3 Camel-hair brush 5.4 Stopwatch or stopclock 6 Sampling and preparation of sample for analysis See BS 684: General introduction. 7 Procedure 7.1 Preparation of test panel. Prepare the test panel by one of the
15、 following methods. 7.1.1 Solvent wash. Wash the panel three times with an excess of a suitable solvent. (e.g. white spirit complying with BS 245 or xylene complying with BS 458) using a clean piece of cloth soaked in the solvent. Allow the clean panel to dry either by evaporation of the solvent or
16、by lightly wiping with a clean linen cloth, if necessary warming very slightly to remove traces of condensed moisture. 7.1.2 Detergent wash. Wash the panel thoroughly in aqueous non-ionic detergent solution and then rinse thoroughly with distilled water. Dry by wiping with a clean linen cloth, if ne
17、cessary warming very slightly to remove traces of condensed moisture. 7.2 Application. Brush the oil on to the surface of a prepared test panel (5.1). 7.3 Drying. Place the panel in a vertical position in a well ventilated room at a temperature of 16 C to 21 C and a relative humidity of 60 % to 70 %
18、 so that the surface of the panel is illuminated by diffused daylight for at least 6 h during each day of the drying period. In order to avoid interference through deposition of moisture on the oil film, take care that throughout the drying process the temperature of the room is above the dew point.
19、 NOTEThe temperatures stated are applicable to temperate climates. In the case of a test carried out in tropical or subtropical climates (or on material intended to be used in tropical or subtropical climates), any higher temperatures up to 35 C may be substituted. The actual temperature and humidit
20、y at which the test is to be carried out should be the subject of agreement between purchaser and vendor. Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 13:15:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 684-1.7:1976 2 BSI 11-1999 7.4 Assessment of surface-drying time after a specified t
21、ime. On completion of the specified period of drying, place the test panel in a horizontal position. Pour approximately 0.5 g of ballotini (5.2) from a height of 150 mm on to the surface of the film. NOTEIt is convenient to pour the ballotini down a glass tube of appropriate length and with an inter
22、nal diameter of approximately 25 mm, in order to avoid undue spreading of the ballotini and thus to enable further tests to be made, if necessary, on other areas of the same panel. CAUTION. Ballotini split on to the floor can constitute a hazard. After 1 min hold the panel at an angle of 20 to the h
23、orizontal, brush lightly with the camel-hair brush (5.3) and examine the film using normal corrected vision. The film is surface-dry if all the ballotini can be brushed away without damage to the surface of the film. 7.5 Determination of surface-drying time. Prepare a number of similarly coated test
24、 panels as described in 7.2 and allow to dry as described in 7.3. At appropriate intervals, starting shortly before the oil film is expected to be surface-dry and using a different panel for each test (or an untouched area of the same panel if the tube described in the note to 7.4 is used), carry ou
25、t the test as described in 7.4 until the test shows the coating to be surface-dry. 8 Expression of results 8.1 Assessment of surface-drying time after a specified time. Express the result as “surface-dry” or “not surface-dry” as appropriate after a drying period of x, where x is the drying period (i
26、n hours) used in the test procedure. 8.2 Determination of surface-drying time. Record the time taken for the oil film to become just surface-dry. 9 Test report See the general instructions and recommendations given in BS 684: General introduction, and state the temperature and humidity if different
27、from those specified (see note to 7.3). Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 13:15:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI blank Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 13:15:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 684-1.7: 1976 BSI 389 Chiswick High R
28、oad London W4 4AL BSI British Standards Institution BSI is the independent national body responsible for preparing British Standards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions British Standards are updated by amendme
29、nt or revision. Users of British Standards should make sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve the quality of our products and services. We would be grateful if anyone finding an inaccuracy or ambiguity while using this British Standard woul
30、d inform the Secretary of the technical committee responsible, the identity of which can be found on the inside front cover. Tel: 020 8996 9000. Fax: 020 8996 7400. BSI offers members an individual updating service called PLUS which ensures that subscribers automatically receive the latest editions
31、of standards. Buying standards Orders for all BSI, international and foreign standards publications should be addressed to Customer Services. Tel: 020 8996 9001. Fax: 020 8996 7001. In response to orders for international standards, it is BSI policy to supply the BSI implementation of those that hav
32、e been published as British Standards, unless otherwise requested. Information on standards BSI provides a wide range of information on national, European and international standards through its Library and its Technical Help to Exporters Service. Various BSI electronic information services are also
33、 available which give details on all its products and services. Contact the Information Centre. Tel: 020 8996 7111. Fax: 020 8996 7048. Subscribing members of BSI are kept up to date with standards developments and receive substantial discounts on the purchase price of standards. For details of thes
34、e and other benefits contact Membership Administration. Tel: 020 8996 7002. Fax: 020 8996 7001. Copyright Copyright subsists in all BSI publications. BSI also holds the copyright, in the UK, of the publications of the international standardization bodies. Except as permitted under the Copyright, Des
35、igns 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. This does not preclude the free use, in the course of implementing the standard,
36、 of necessary details such as symbols, and size, type or grade designations. If these details are to be used for any other purpose than implementation then the prior written permission of BSI must be obtained. If permission is granted, the terms may include royalty payments or a licensing agreement. Details and advice can be obtained from the Copyright Manager. Tel: 020 8996 7070. Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 13:15:41 GMT+00:00 2006, Uncontrolled Copy, (c) BSI