1、BRITISH STANDARD BS EN 60654-4:1998 IEC654-4: 1987 Incorporating Amendment No.1 to BS5967-4:1988 (renumbers the BS as BS EN60654-4:1998) Operating conditions for industrial-process measurement and control equipment Part 4: Corrosive and erosive influences The European Standard EN60654-4:1997 has the
2、 status of a British Standard ICS 25.040.40BSEN60654-4:1998 This British Standard, having been prepared under the directionof the Industrial-process Measurement and Control Standards Committee, waspublished under the authorityof the Board of BSI andcomes into effect on 29April1988 BSI 04-1999 The fo
3、llowing BSI references relate to the work on this standard: Committee reference PCL/1 Draft for comment 85/22036 DC ISBN 0 580 16465 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Industrial-process Measurement and Control Standards C
4、ommittee (PCL/-) toTechnical Committee PCL/1, upon which the following bodies were represented: British Coal British Gas plc British Pressure Gauge Manufacturers Association Department of Energy (Gas and Oil Measurement Branch) Department of Trade and Industry (National Weights and MeasuresLaborator
5、y) Energy Industries Council Engineering Equipment and Materials Users Association GAMBICA (BEAMA Ltd) Health and Safety Executive Institution of Gas Engineers Coopted members Amendments issued since publication Amd. No. Date of issue Comments 9957 April 1998 Implementation of European StandardBSEN6
6、0654-4:1998 BSI 04-1999 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 1 Scope 3 2 Object 3 3 General 3 4 Non-solid substances 4 5 Gases and vapours 4 6 Aerosols 6 7 Liquids 6 8 Solid substances 6 9 Flora and fauna 8 Appendix A Industrial contaminants 9 App
7、endix B Methods of classification of reactive environments 9 Table I Classification of chemically active contaminants (in cm 3 /m 3 )(PPM in old units) 5 Table II Untitled 6 Table B.I Classification of reactive environments of copper film formation 9BSEN60654-4:1998 ii BSI 04-1999 National foreword
8、This British Standard has been prepared by Subcommittee GEL/65/1 (formerlyPCL/1), and is the English language version of EN60654-4:1997. It is identical with IEC654-4:1987 published by the International Electrotechnical Commission (IEC). A British Standard does not purport to include all the necessa
9、ry provisions 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, theEN ti
10、tle page, pages 2 to 11and a 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.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN60654-4 August 1997 ICS 25.040.40 Descrip
11、tors: Industrial process,measurement, control, operating conditions, corrosive and erosive influences English version Operating conditions for industrial-process measurementandcontrol equipment Part 4: Corrosiveanderosiveinfluences (IEC 60654-4:1987) Conditions de fonctionnement pour les matriels de
12、 mesure et commande dans les processus industriels Partie 4: Influences de la corrosion et de lrosion (CEI 60654-4:1987) Einsatzbedingungen fr Me-, Steuer- und Regeleinrichtungen in der industriellen Prozetechnick Teil 4: Korrosive und erosive Einflsse (IEC 60654-4:1987) This European Standard was a
13、pproved by CENELEC on 1997-07-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such n
14、ational standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own lang
15、uage and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, S
16、witzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1997 CENELEC All rights of exploitation in any form
17、 and by any means reserved worldwide for CENELEC members. Ref. No. EN60654-4:1997 EEN60654-4:1997 BSI 04-1999 2 Foreword The text of the International Standard IEC60654-4:1987, prepared by SC65A, System aspects, of IEC TC65, Industrial-process measurement and control, was submitted to the formal vot
18、e and was approved by CENELEC as EN60654-4 on1997-07-01 without any modification. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 1998-06-01 latest date by which the national
19、standards conflicting with the EN have to be withdrawn (dow) 1998-06-01BSEN60654-4:1998 BSI 04-1999 3 1 Scope Part 4 of the standard considers the corrosive and erosive industrial environment to which land-based and off-shore, industrial-process measurement and control systems or parts of systems ma
20、y be exposed during operation, during periods when they are installed but inactive, during storage or transportation. Maintenance and repair conditions are excluded from this part. The environmental influences considered in this part are limited to those which may directly affect performance of proc
21、ess-measurement and control systems or parts of such systems. Effects of the specific environmental conditions on personnel are not within the scope of this part. The appropriate values of the physical or chemical parameters listed here as well as the qualitative descriptions of the environment shou
22、ld be used to define local environments in which equipment is expected to operate, be transported and stored. Only conditions as such are considered; the resulting effects of these conditions on instrument performance are specifically excluded. Many environmental conditions listed in this part are d
23、ifficult to classify so that a qualitative description is used to characterize the environment. 2 Object The object of Part 4 of the standard is to provide users and suppliers of industrial-process measurement and control systems and parts of such systems with a uniform listing and classification of
24、 corrosive and erosive environmental conditions to which equipment may be exposed in specified locations during operation, storage, handling and transportation. Conditions for transportation are for equipment in suitable packages to prevent damage. The listed environmental conditions are intended to
25、 serve as a basis for comprehensive specifications. One of the objects of this part is to minimize problems which might result from neglecting considerations of specific operating conditions affecting performance of systems and parts of systems. An additional object of this part is to aid in the cho
26、ice of specific limit values for use in the development of evaluation specifications for industrial-process measurement and control equipment. 3 General Industrial-process measurement and control equipment is used all over the earth, thus being exposed to the characteristic environmental conditions
27、of fauna and flora of tropical, temperate and arctic climates, as well as deserts, jungles, mountains and the sea. Superimposed on these basic environmental influences and in addition to the general level of ambient pollution prevalent in industrialized areas where process control equipment and syst
28、ems are heavily utilized, it should be recognized that higher levels of contamination do generally exist in the localized areas where the process control equipment is deployed, as contaminants are introduced into the environment by the very process that is being controlled. These higher levels of co
29、ntamination can occur permanently or temporarily. In many cases the effects on measurement and control equipment are proportional to the concentration, temperature and the period of exposure, these effects being often increased by humidity. It is however very difficult to describe an environment by
30、specifying the concentration of the contaminant against time. Therefore, the concept of the average value was used as a basis for quantitatively classifying the chemically active substances. But it is recognized that special damage may be caused by short-time high concentration (peak value) of corro
31、sive contaminants, therefore the peak values as defined below have been incorporated in the classification. In Appendix A is given a listing of industrial contaminants associated with various process plants. It is a guide to highlight the specific contaminants introduced by industrial processes. Atm
32、ospheric contamination to which systems and parts of systems may be exposed include gases, vapours, liquids and solids. The effects of these contaminants can be various, such as the corrosive effects from chemically active contaminants, erosive effects from sand blasting and clogging by dusts. The d
33、ifferent kinds of contaminants can also be present in combinations whereby more severe environmental conditions can arise such as high humidity combined with chlorine gas; therefore, the ambient temperature and relative humidity should be specified. It is practically impossible to classify all the d
34、ifferent environments, due to the unlimited number of possible combinations and associated large number of effects and severities. It is recognized that the effects of gases, vapours and liquids are primarily corrosive while solid contaminants may cause adverse erosive, corrosive, thermal or electro
35、magnetic effects.BSEN60654-4:1998 4 BSI 04-1999 Therefore, Clauses4, 5, 6 and7 classify the corrosive effects of non-solid chemically active substances. Clauses8 and9 are enumerations of other environmental effects on instrumentation in which solid active substances are listed and the effects of flo
36、ra and fauna are briefly mentioned. 4 Non-solid substances Non-solid substances are only chemically active. They are therefore classified according to the average and peak value of their concentration. 4.1 Definitions The following definitions are required to understand this part. One-half hour mean
37、 value is defined as where x is the measured or expected contaminant concentration. Peak value is the maximum measured or expected one-half hour mean value recognized over a year. Mean value is the arithmetic mean of a statistically sufficient number of measured or expected one-half hour mean values
38、. NOTEA one hour mean value may be used where legal. 5 Gases and vapours The classes in Table I recognize that average concentrations and peak values shall both be considered to properly classify an environment. Peak values have been integrated on a hour basis. Chemical agents (e.g.SO 2or HF) may va
39、ry greatly in their reactivity rate over a h period. Therefore, the relationship of peak value to average value may vary with each contaminant. The classification of environment by category should be determined by the highest class if average and peak values are not in the same category. An alternat
40、e method of classification based on copper reactivity rates is shown in Appendix B. 5.1 Contamination effects Each site may have different combinations and concentration levels of corrosive gaseous contaminants. Performance degradation can occur rapidly or over many years, depending on the particula
41、r concentration levels and combinations present at a site. The following paragraphs describe how various contaminants contribute to equipment performance degradation. 5.2 Inorganic chlorine compounds (expressed as Cl 2inTable I) This group contains both strong oxidants (chlorine,chlorine dioxide) an
42、d compounds such as hydrogen chloride, so reactivity will depend upon the specific gas composition. In the presence of moisture, these gases generate chloride ions which react readily with copper, tin, silver and iron alloys. These reactions are significant even when the gases are present at low lev
43、els. These reactions are attenuated in dry atmospheres. At higher concentrations, many elastomers and some plastics are oxidized by exposure to chlorinated gases. Particular care shall be given to equipment which is exposed to atmospheres which contain chlorinated contaminants. Sources of chloride i
44、ons, such as cleaning compounds and cooling tower vapours, etc., should be considered when classifying. 5.2.1 Active sulphurs (expressedasH 2 Sin Table I) This group includes hydrogen sulphide, elemental sulphur and organic sulphur compounds such as the mercaptans. When present at low levels, they r
45、apidly attack copper, silver and iron alloys. The presence of moisture and small amounts of inorganic chlorine compounds greatly accelerates sulphide corrosion. Note, however, that attack still occurs in low relative humidity environments. Active sulphurs rank alongside inorganic chlorides as the pr
46、edominant cause of atmospheric corrosion in the process industries. 5.2.2 Sulphur oxides (expressed as SO 2in Table I) Oxidized forms of sulphur (SO 2 , SO 3 ) are generated as combustion products of sulphur-bearing fossil fuels. Low levels of sulphur oxides can passivate reactive metals and thus re
47、tard corrosion. At higher levels they attack certain types of metals, elastomers and plastics. The reactions with metals normally occur when these gases dissolve in water to form sulphurous and sulphuric acid. 5.2.3 Nitrogen oxides (expressed as NO xin Table I) NO xcompounds (NO, NO 2 , N 2 O 4 ) ar
48、e formed as combustion products of fossil fuels and have a critical role in the formation of ozone in the atmosphere. They are also believed to have a catalytic effect on corrosion of base metals by chlorides and sulphides. In the presence of moisture, these gases form nitric acid which, in turn, at
49、tacks most common metals. 1 h - x 0 h dtBSEN60654-4:1998 BSI 04-1999 5 5.2.4 Hydrogen fluoride (expressed as HF in Table I) This compound is a member of the halogen family and reacts like inorganic chloride compounds. 5.2.5 Ammonia and derivatives (expressed asNH 3 in Table I) Reduced forms of nitrogen (ammonia, amines, ammonium ions) occur mainly in fertilizer plants, agricultural applications, and chemical plants. Copper and copper alloys are particularly susceptible to corrosion in ammonia environments. 5.2.6 Photochemical specie
