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1、BRITISH STANDARD BS 5536:1988 Recommendations for Preparation of technical drawings for microfilming UDC 778.14:744.4 Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:59:20 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5536:1988 This British Standard, having been prepared under the directio
2、n of the General Mechanical Engineering Standards Committee, was published under the authority of the Board of BSI and comes into effect on 31 August 1988 BSI 03-1999 First published January 1978 First revision August 1988 The following BSI references relate to the work on this standard: Committee r
3、eference GME/4 Draft for comment 87/71846 DC ISBN 0 580 16778 X Committees responsible for this British Standard The preparation of this British Standard was entrusted by the General Mechanical Engineering Standards Committee (GME/-) to Technical Committee GME/4, upon which the following bodies were
4、 represented: Amalgamated Union of Engineering Workers (Technical and Supervisory Section) British Paper and Board Industry Federation British Railways Board British Standards Society Drawing Office Material Manufacturers and Dealers Association Electricity Supply Industry in England and Wales Elect
5、ronic Engineering Association Engineering Equipment and Materials Users Association Gauge and Tool Makers Association Institution of Chemical Engineers Institution of Electrical Engineers Institution of Electronic and Radio Engineers Institution of Engineering Designers Institution of Mechanical Eng
6、ineers Institution of Production Engineers Ministry of Defence Society of British Aerospace Companies Limited Telecommunication Engineering and Manufacturing Association United Kingdom Atomic Energy Authority The following body was also represented in the drafting of the standard, through subcommitt
7、ees and panels: Post Office Amendments issued since publication Amd. No.Date of issueComments Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:59:20 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5536:1988 BSI 03-1999i Contents Page Committees responsibleInside front cover Forewordii 1Scope1
8、 2Drawing sheets1 3Materials1 4Presentation1 5Lines1 6Form, size and spacing of characters2 7Scale on drawings2 8Care of drawings3 9Original drawings3 Figure 1 Example of thin material in section2 Figure 2 Examples of letters and numerals3 Figure 3 Example of a drawing suitable for microfilming4 Tab
9、le 1 Drawing sheet sizes and frame sizes (trimmed)1 Table 2 Minimum character height for capital letters and numerals2 Publications referred toInside back cover Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:59:20 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5536:1988 ii BSI 03-1999 Fore
10、word This revision of BS 5536 has been prepared under the direction of the General Mechanical Engineering Standards Committee and supersedes BS 5536:1978 which was published as a specification and is now withdrawn. It is intended for all technical drawing that may be microfilmed and is complementary
11、 to BS 308, BS 1192 and BS 5070 which are also recommendations. It is related to ISO 6428, published by the International Organization for Standardization (ISO). Whereas BS 5536:1978 was presented as a specification, having regard to progress in standards making policy in the interim, it became appa
12、rent that this subject was no longer suitable as a specification and this revision is presented in the form of recommendations. Technical drawings complying with the recommendations of this standard and BS 308, BS 1192 or BS 5070 should be capable of being recorded on, and subsequently reproduced fr
13、om, microfilm without significant loss of quality at camera reduction ratios up to 1 : 30. The draughting requirements for microfilming are important and therefore all drawings and diagrams, whether produced manually or by machine and which comply with the recommendations of this standard, will enab
14、le any recipient of the microfilm, whether in the United Kingdom or overseas, to obtain a satisfactory reproduction. 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
15、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 to 4, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendme
16、nts incorporated. This will be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:59:20 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5536:1988 BSI 03-19991 1 Scope This British Standard gives recommendations for the preparation and
17、care of all types of technical drawings intended for microfilming in accordance with BS 4210. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 2 Drawing sheets 2.1 Sizes Drawing sheets should comply with the sizes given in BS 3429 and Table 1. Draw
18、ing sheets larger than A0 size should be avoided owing to the limitations of microfilming equipment normally available (see 2.2). 2.2 Drawing frame and centring marks The most critical dimensions are those of the drawing frame which relate to the nominal sheet sizes as given in Table 1. A centring m
19、ark in the form of a line should be shown at the centre of each of the four sides of the drawing frame given in Table 1 and to be within a tolerance of 1 mm of the true position. If the use of a sheet larger than A0 is essential, then additional marks will be needed on the drawing to allow for filmi
20、ng of the drawing on more than one microfilm frame. In this instance the centring marks should be placed to coincide with the intended centre position of each individual microfilm frame and to permit an overlap of approximately 100 mm between frames. In this case the position of the centring marks w
21、ill not need to be as critical as for the drawing frame sizes given in Table 1. Table 1 Drawing sheet sizes and frame sizes (trimmed) 3 Materials 3.1 Drawing sheets should have a matt surface so as to minimize reflectance. 3.2 On translucent material all drawing information including the pre-printin
22、g should preferably appear on the front of the drawing sheet. Some loss of microfilm quality may result if pre-printing and other information is filmed through the material thickness. 3.3 Pencils and inks that give lines with matt surfaces should be used. In this respect polymer type pencil leads ar
23、e superior on draughting film to graphite (see also 8.4). 3.4 The drawing board facing or an intermediate backing sheet, should be chosen so as to minimize indentation of the drawing sheet as indentations can detract from the clarity of reproduction through the effects of reflected and refracted lig
24、ht and can cause ghost images to appear when microfilming. NOTEAdhesive overlays may deteriorate with age and accumulate dust and such defects may then adversely affect the quality of the microfilm. 4 Presentation Views should be spaced so that dimensions and notes can be clearly presented. Areas of
25、 fine detail should be shown suitably enlarged (see Figure 3). 5 Lines 5.1 All lines, including those added in any revision of the drawing, should be consistently black and dense. The lines on any one drawing sheet should preferably be entirely in pencil or entirely in ink. If pencil and ink are use
26、d on the same drawing, every effort should be made to ensure that uniform density and reflectance are maintained. 5.2 Each type of line should be of consistent thickness. The minimum thickness of line for satisfactory microfilming is 0.25 mm. 5.3 To allow for limitations on print-out and viewing of
27、reduced microfilm copies, adjacent lines should be spaced not less than 1 mm apart. In some cases this may result in certain features having to be exaggerated locally on the drawing. Thin material in section may be shown as single solid lines in preference to showing the material thickness out of sc
28、ale. When adjacent parts are thus shown, a space of not less than 1 mm should be left between them for clarity (see Figure 1). Black areas wider than 3 mm should be avoided due to the limitations of some print-out processes. DesignationSizeMinimum border width from drawing frame to edge of sheet mmm
29、m A0 A1 A2 A3 A4 841 1 189 594 841 420 594 297 420 210 297 20 20 10 10 10 Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:59:20 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5536:1988 2 BSI 03-1999 6 Form, size and spacing of characters 6.1 It is important that characters should be uniform
30、 and equally capable of being produced by hand, stencil, machine or other means. The characters on the drawing should remain legible not only in full size copy but in the form of reduced copy or as an image on a microfilm viewing screen. Clarity, style, size and spacing are important, particularly f
31、or numerals, as unlike letters they rarely fall into identifiable patterns and have to be read individually. Characters should be open form and devoid of embellishments. All strokes should be black and of consistent density compatible with the line work. Care should be taken that sufficient space ex
32、ists between characters and parts of characters to ensure that “filling in” will not take place during reproduction. 6.2 No particular style of lettering is recommended; the aim should be to produce legible and unambiguous characters. Where confusion may arise between a capital letter I and the nume
33、ral 1 it is recommended that a top serif be added to the numeral 1. Particular care should also be taken to ensure that such characters as B and 8, Z and 2 and S and 5, will not be confused. The smaller angles contained in sloping letters may prove slightly inferior in microfilm reproduction. Capita
34、l letters are preferred to lower case as they are less congested and are less likely to be misread when reduced in size. Lower case letters should be restricted to instances where they form part of a standard symbol, code or abbreviation. Table 2 gives minimum recommended heights for capital letters
35、. However, when lower case letters are used they should be proportioned so that the body height is approximately 0.6 times the capital letter height. The numerator and denominator of a fraction should each be of the size recommended for letters and numerals given in Table 2. NOTEThe examples in Figu
36、re 2, which have been produced by the use of stencils, are provided as a guide only. Table 2 Minimum character height for capital letters and numerals 6.3 The stroke thickness of the character should be approximately 0.1 times the height and the clear space between characters and parts of characters
37、 should be approximately 0.7 mm for capitals and numerals of 2.5 mm height, other sizes being in proportion. The space between lines of lettering should be not less than half the character height, but for titles closer spacing may sometimes be unavoidable. 6.4 To facilitate reading from a microfilm
38、viewing screen, all notes should be placed so that they can be read from the same direction as the format of the drawing. Where a long vertical object is to be drawn horizontally on a landscape drawing sheet, the base of the object should be drawn on the right-hand side and the width dimensions shou
39、ld be readable from the right-hand side of the drawing. 6.5 When mechanical means for lettering are used (such as typewriters, plotters, etc.), the density should, as far as possible, be the same as that of the other lines on the document. The type of lettering and its dimensions should be similar t
40、o those shown in Figure 2. NOTE 1Clarity of character image can be achieved by using only capital letters and using one-time printing ribbons. NOTE 2Typing on polyester material requires a special total transfer ribbon which has low reflectance and high density. 7 Scale on drawings Because the size
41、of the copy printed from microfilm will almost certainly be different from the size of the original, it is essential that reference to the scale used should be stated on the drawing, e.g. “Original scale 1 : 5”. The original scale should be indicated by means of a relevant numbered scale bar. If des
42、ired, a warning against scaling the drawing may be given. Figure 1 Example of thin material in section ApplicationDrawing sheet sizeMinimum character height mm Drawing number and title A0, A1, A2 and A37 A45 Dimensions and all other characters A03.5 A1, A2, A3 and A42.5 Licensed Copy: sheffieldun sh
43、effieldun, na, Fri Dec 01 09:59:20 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5536:1988 BSI 03-19993 8 Care of drawings 8.1 For storage, drawings should preferably be laid flat or be suspended. They should not be folded, but drawings on draughting film may be rolled and placed in a protective tub
44、e, the diameter of which should be chosen to suit the material composition. For transit, drawings should be wrapped (drawing side inwards) and retained around a tube of not less than 75 mm diameter (this value may be reduced for draughting film) then placed in a protective outer tube. 8.2 Edge bindi
45、ng of drawings intended for microfilming is not recommended. Where edge binding of drawings is undertaken, the shrinkage properties of the tape used should be compatible with those of the drawing sheet material. 8.3 When erasures are necessary, care should be taken to ensure that any impairment of t
46、he drawing surface is minimal. 8.4 Where, contrary to the recommendations given in 3.3, drawings are prepared with graphite pencils, consideration should be given to the use of a non-toxic fixative to prevent smudging. NOTEThe use of fixatives is likely to complicate satisfactory erasure. 9 Original
47、 drawings The best microfilming results will be obtained using the original ink (or pencil) drawing. When a design change is made or a different use is envisaged that requires a new drawing to be made, consideration should be given to replacing the original drawing with a reproducible and then modif
48、ying the original for the new purpose. This procedure will minimize the microfilming of reproduced drawings and increase the use of the high quality, high cost original. NOTEThese examples, which have been produced by the use of stencils, are provided as a guide only. Figure 2 Examples of letters an
49、d numerals Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:59:20 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5536:1988 4 BSI 03-1999 NOTEThe circled numbers refer to clauses in the text. Figure 3 Example of a drawing suitable for microfilming Licensed Copy: sheffieldun sheffieldun, na, Fri Dec 01 09:59:20 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 5536:1988 BSI 03-1999 Publications referred to BS 308, Engineering drawing practice1). BS 1192, Construction drawing practice1). BS 3429, Specification for sizes of drawing sheets. BS
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