1、BRITISH STANDARD BS 5070-3: 1988 Engineering diagram drawing practice Part 3: Recommendations for mechanical/fluid flow diagrams UDC 744:003.63:621 BS 5070-3:1988 This British Standard, having been prepared under the direction of the General Mechanical Engineering Standards Committee, was published
2、under the authority of the Board of BSI and comes into effect on 29 April 1988 BSI 15 September 2002 The following BSI references relate to the work on this standard: Committee reference GME/4 Draft for comment 85/79731 DC ISBN 0 580 16270 2 Committees responsible for this British Standard The prepa
3、ration 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 represented: Amalgamated Union of Engineering Workers (Technical and Supervisory Section) British Paper and Board Industry
4、 Federation (PIF) British Railways Board British Standards Society Drawing Office Material Manufacturers and Dealers Association Electricity Supply Industry in England and Wales Electronic Engineering Association Engineering Equipment and Materials Users Association Gauge and Tool Makers Association
5、 Institution of Electrical Engineers Institution of Electronic and Radio Engineers Institution of Engineering Designers Institution of Mechanical Engineers Institution of Production Engineers Ministry of Defence Society of British Aerospace Companies Ltd Society of Motor Manufacturers and Traders Li
6、mited Telecommunication Engineering and Manufacturing Association United Kingdom Atomic Energy Authority Amendments issued since publication Amd. No. Date CommentsBS 5070-3:1988 BSI 15 September 2002 i Contents Page Committees responsible inside front Foreword ii 1S c o p e 1 2 Principal types of di
7、agrams 1 3 Principles of presentation 1 4 Block diagram 4 5F l o w d i a g r a m 5 6 Circuit diagram (fluid) 5 7 System and piping diagrams 6 8 Piping and instrumentation diagrams (P and IDs) 6 9 Supplementary diagrams 7 Appendix A. Examples of diagrams 8 Appendix B. British Standards detailing grap
8、hic symbols for use in engineering diagrams 40 Figure 1 Line cross-overs 3 Figure 2 Line junctions 3 Figure 3 Omission of lines 4 Figure 4 Block diagram: carbon dioxide removal unit 9 Figure 5 Flow diagram: carbon dioxide removal unit 11 Figure 6 Piping and instrumentation diagram: carbon dioxide re
9、moval unit 13 Figure 7 Block diagram: steam and feed system 15 Figure 8 Flow diagram: steam and feed system 17 Figure 9 System diagram: steam and feed system 19 Figure 10 Piping diagram: filtration unit 21 Figure 11 Circuit diagram: hydraulic power pack 23 Figure 12 Circuit diagram: hydraulics 25 Fi
10、gure 13 Circuit diagram: pneumatics 27 Figure 14 Circuit diagram: pneumatics 29 Figure 15 Location diagram: aircraft hydraulics 31 Figure 16 Topographical diagram: fluid distribution system 33 Figure 17 Supplementary diagram: ships ballast mimic diagram 35 Figure 18 Supplementary diagram: ships stea
11、m and feed system 37 Figure 19 Installation drawing: gas drier 39 Table 1 Types of line 2 Table 2 Applications of arrows 4BS 5070-3:1988 ii BSI 15 September 2002 Foreword This part of BS 5070 has been prepared under the direction of the General Mechanical Engineering Standards Committee and, togethe
12、r with Part 1 and Part 2 * , supersedes BS 5070:1974 which is now withdrawn. The 1974 edition set out recommendations for drawing practice to be followed in preparing engineering diagrams in all fields of engineering with a view to securing uniformity between one drawing office and another in the sa
13、me industry. It also aimed to increase uniformity between one field of engineering and another in the basic principles involved and in the designations for different types of diagram. Attention is drawn to BS 5070 being a companion standard to BS 308; the latter covers engineering drawing practice u
14、sed in a wide range of engineering disciplines. Commonly, as a diagram can be called a “drawing” and a drawing can be called a “diagram”, it is useful to summarize the difference in the scopes of these standards. BS 308 covers what are commonly accepted to be drawings that define shape, size and for
15、m. BS 5070 covers the drawing of diagrams that are normally associated with flow of one sort or another and which relate components (usually indicated by symbols) functionally one to another by the use of lines, but do not depict their shape, size or form; neither do they in general indicate physica
16、l connections or locations. From experience with the 1974 edition it was decided that for this first revision, whilst bearing in mind the long term aim of uniformity of conventions, there was a need for more comprehensive treatment of the varying requirements of differing industries and for more car
17、eful attention to their presentation. BS 5070 is therefore now revised in parts by which the practice and conventions of several disciplines and industries are collected into three groups. Part 1 covers general principles common to all subsequent parts, which in turn deal particularly with electrote
18、chnology; mechanical and fluid flow and systems; and logic. This standard gives recommendations for the drawing of engineering diagrams using the symbols given in relevant British Standards. It does not itself originate symbols. The diagrams in this standard contain symbols as they appear in the par
19、ticular standards current at the time this publication was prepared. However, although every effort has been made to ensure that correct and current symbols have been used, it has to be recognized that the particular symbols standards are themselves subject to periodic review. It is therefore stress
20、ed that the relevant symbols standards, and not this standard, have to be consulted to obtain definitive symbols. The recommendations of this standard have been established having regard to the requirements of microfilming. Diagrams prepared in accordance with this standard should be suitable for mi
21、crofilming and reduced-size reproduction techniques. During the course of this revision particular attention has been paid to developments in computer aided machine draughting and it has been established that such machines are currently capable of complying with this standard. Any minor exceptions d
22、ue to the limitations of a particular system would not be expected to prejudice the understanding of a diagram otherwise claimed to comply with this standard. It is recognized that though this standard is published in a number of parts, there may be instances when certain recommendations and descrip
23、tions are repeated. This has been kept to a minimum and it is hoped that all the needs of any specialized engineering discipline are contained in the part of this standard that deals with those specific needs. This part of this standard deals with a variety of non-electrical diagrams including contr
24、ol and flow; transfer of materials (both fluids, i.e. liquids, vapours and gases, and solids); and energy transfer (hydraulic, pneumatic and mechanical). * An additional Part 4 is also in preparationBS 5070-3:1988 BSI 15 September 2002 iii Part 1 of this standard deals with general principles of dia
25、gram drawing and is the base document. Part 2 of this standard deals with all forms of diagrams in electrical, electronics and telecommunications engineering. Part 4 of this standard deals with logic diagrams. Engineering diagrams are a major factor in the development of a project. They are used eit
26、her to build complex engineering plants or the smallest item of equipment. It is important that the information contained should be complete, easily understood and maintained in an up-to-date condition. In the case of certified “as-built” diagrams a design change procedure is recommended for record
27、and historic purposes. Such a procedure is the key to ensuring control of cost, time and technical accuracy for the project. Sequencing or progression of diagrams can be variable. It is, however, recommended that guide lines be introduced at the commencement of a project to present the assembly of i
28、nformation, proceeding from one diagram to the other. Compliance with a British Standard does not of itself confer immunity from legal obligations. Notes on the presentation of this standard NOTE 1 The figures illustrating the text in this standard are independent and each is selected solely for its
29、 simplicity and clarity to illustrate only the text to which it relates. They are not the only possible examples and they are not intended as design examples or to be fully working diagrams, but otherwise are drawn according to the basic recommendations of this standard. NOTE 2 Numerical values of c
30、omponents given in the figures throughout are arbitrarily chosen to assist in illustrating the point under consideration; they are typical and are not given as recommendations. NOTE 3 In the figures in this standard, a convention is adopted of using capital letters for notes that would appear as par
31、t of the drawing and lower case letters are used for notes explaining the point under consideration in relation to the text. An exception to this may be found in some diagrams where unit symbols are customarily written in lower case. Summary of Pages This document comprises a front cover, inside fro
32、nt cover, pages i to iv, pages 1 to 41 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.iv blankBS 5070-3:1988 BSI 15 September 2002 1 1 Scope This part of BS 5070 gives recommendations for the practice to be followed in preparing mech
33、anical, process and fluid flow diagrams. It covers all aspects of diagram representation except the choice of symbols for particular components; this is the subject of BS 1553 and other relevant standards giving symbols for specific industrial use. This part of this standard should always be used in
34、 conjunction with BS 5070-1 and the relevant symbol standards when preparing mechanical, process and fluid flow diagrams. NOTE 1 The relevant part of BS 5775 should be complied with for the correct application of units and symbols for quantities. NOTE 2 British Standards detailing graphic symbols fo
35、r use in engineering diagrams are listed in Appendix B. NOTE 3 The titles of the publications referred to in this standard are listed on the inside back cover. 2 Principal types of diagrams The following list, covered by this part of BS 5070, is of the main classification of diagrams used by industr
36、y and has been prepared in order to reduce ambiguity and to achieve standardization in terminology: a) Block diagram. b) Flow/process diagram. c) Circuit diagram (fluid). d) Piping/system diagrams. e) Piping and instrumentation line diagram (P and ID). f) Installation diagram. g) Supplementary diagr
37、am. In complex plants it is desirable to prepare a hierarchy of diagrams whereby the user is guided through basic simple concepts down to detail information stages. 3 Principles of presentation 3.1 General For the purposes of this part of BS 5070 a symbol is a symbolic graphic convention representin
38、g a discrete manufactured device contributing to the functioning of a system or circuit (see Appendix A.). A line is a graphic convention showing how devices (represented by symbols) are connected. A variety of types of line, some with embellishments, are used to represent connections having differe
39、nt functions. Table 1 shows typical applications of different line types.BS 5070-3:1988 2 BSI 15 September 2002 Table 1 Types of line Line Description General application Particular application Thickness Process engineering (e.g. chemical) Pneumatic hydraulic (fluid) Instrument control mm Continuous
40、 double width Primary link lines Primary process pipelines Main pressure pipelines Single line representation 0.7 to 1.0 Continuous single width General contents of diagram Secondary pipelines or plant outlines Impulse lines 0.5 Short dash Secondary or hidden line Control, vents or drains Interconne
41、ct signal lines electrical * 0.5 Short chain Differentiating similar equipment Differentiating pipes or existing items 0.5 Long chain Boundaries and centre lines Boundaries 0.3 Double continuous Special purpose Mechanical linkage 0.5 Continuous single with short dash Insulated pipelines Insulated or
42、 traced pipelines 0.5 Single width intermittent single hatch Pneumatic instrument impulse Pneumatic instrument impulse 0.5 Single width intermittent inverted V Alternative pneumatic impulse Alternative pneumatic instrument impulse Pneumatic impulse lines 0.5 Single width intermittent open E Alternat
43、ive electrical impulse Alternative electrical impulse Electrical impulse lines 0.5 Single width intermittent cross symbol Capillary Replenish pipelines Capillary pipelines 0.5 Single width intermittent double arrow Transmitted radiation Transmitted radiation Transmitted radiation 0.5 Single width in
44、termittent letter L Hydraulic Hydraulic impulse lines 0.5 * The single width intermittent “open E” line may be used as an alternative. The short dash line may be used as an alternative.BS 5070-3:1988 BSI 15 September 2002 3 3.2 Cross-overs and junction of lines 3.2.1 Cross-overs. The understanding o
45、f a process or item of equipment will be helped by clearly identifying cross-over and junction positions. A cross-over without joining should be shown at right angles and without change of direction. Three methods are acceptable and are of equal status; however, on any one diagram or set of diagrams
46、 only one method should be used (see Figure 1 ). Where method 2 is adopted the jumper or bridge should preferably be placed in the horizontal line. 3.2.2 Junctions. It is recommended that no more than two connecting lines should be shown coming to a point to form a junction (see Figure 2). 3.3 Omiss
47、ion of lines One of two methods should be employed where it is possible to avoid a multiplicity of long parallel uninterrupted lines across a diagram. Figure 3(a) illustrates the method where the length of line is omitted and each cut end is suitably described and referenced. Figure 3(b) illustrates
48、 the method whereby single line representation can be applied. NOTE Methods of omitting lines on control instrumentation systems are given in BS 5070-2. Figure 1 Line cross-overs Figure 2 Line junctionsBS 5070-3:1988 4 BSI 15 September 2002 3.4 Arrows The particular uses of arrows should be as shown
49、 in Table 2. Table 2 Applications of arrows 4 Block diagram 4.1 General The purpose of a block diagram is to show the essentials of an installation in sufficient block outline to indicate the main design features. It is a relatively simple diagram in which an installation or item of equipment, together with functional inter-relationships are represented by block symbols or annotated enclosures, without showing all the connections (see
