1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationPD CEN/TR 16395:2012Gas Infrastructure CEN/TC234 Pressure Definitions Guideline DocumentPD CEN/TR 16395:2012 PUBLISHED DOCUMENTNational forewordThis Published Document is the UK
2、implementation of CEN/TR16395:2012.The UK participation in its preparation was entrusted to TechnicalCommittee GSE/33, Gas supply.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions
3、of a contract. Users are responsible for its correctapplication. The British Standards Institution 2012. Published by BSI StandardsLimited 2012ISBN 978 0 580 77705 9ICS 01.040.23; 01.040.91; 23.040Compliance with a British Standard cannot confer immunity fromlegal obligations.This Published Document
4、 was published under the authority of theStandards Policy and Strategy Committee on 31 October 2012.Amendments issued since publicationDate Text affectedPD CEN/TR 16395:2012TECHNICAL REPORT RAPPORT TECHNIQUE TECHNISCHER BERICHT CEN/TR 16395 October 2012 ICS 01.040.23; 01.040.91; 23.040.01; 91.140.40
5、 English Version Gas Infrastructure - CEN/TC 234 Pressure Definitions - Guideline Document Infrastructures gazires - Dfinitions des pressions du CEN/TC 234 - Lignes directrices Gasinfrastruktur - CEN/TC 234 Druckdefinitionen - Leitliniendokument This Technical Report was approved by CEN on 24 June 2
6、012. It has been drawn up by the Technical Committee CEN/TC 234. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
7、Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B
8、-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. CEN/TR 16395:2012: EPD CEN/TR 16395:2012CEN/TR 16395:2012 (E) 2 Contents Page Foreword 3Introduction .41 Scope 62 Normative references 63 Terms and definitions .63.1
9、Key pressure definitions used in CEN/TC 234 standards .63.2 Derived pressure definitions used in CEN/TC 234 standards .63.3 Commonly used pressure definitions in European product standards .74 Explanation of Gas pressure definitions for gas transport and distribution systems .74.1 General 74.2 Press
10、ure demarcation .84.3 Operating conditions .84.3.1 Normal operating conditions 84.3.2 Gas pressure under incidental operating conditions 84.4 Design pressure .94.5 Test pressures .94.6 Equipment in the scope of the European Pressure Equipment Directive .95 Relationships between MOP, TOP and MIP and
11、test pressures 10Annex A (informative) Examples of relationships between pressure designations . 11Annex B (informative) Industrial installations according to EN 15001 . 13Bibliography . 14PD CEN/TR 16395:2012CEN/TR 16395:2012 (E) 3 Foreword This document (CEN/TR 16395:2012) has been prepared by Tec
12、hnical Committee CEN/TC 234 “Gas Infrastructure”, the secretariat of which is held by DIN. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rig
13、hts. Operating pressure levels of gas infrastructure differ from one country to another in the European Union. This is due to many different factors, such as the history of gas systems, technologies and materials used and technical constraints. When beginning to draft the functional standards on gas
14、 infrastructure, CEN/TC 234 recognised various pressure levels and ranges in the European member countries, which are to some extent laid down in national laws. To form a consensus for the standardisation work, all pressure levels used in Europe have been brought together and classified in ranges. T
15、his subdivision in pressure levels should permit the manufacturers of components to focus on a limited number of designs in order to reduce the costs. PD CEN/TR 16395:2012CEN/TR 16395:2012 (E) 4 Introduction Background The standards issued by CEN/TC 234 “Gas Infrastructure“ contain a large number of
16、 definitions used for the design, testing and operation of the different parts of the gas infrastructure. This document clarifies the CEN/TC 234 concept behind the definitions and advises how to use the definitions correctly and consistently. In order to further that goal, an inventory of existing d
17、efinitions is compiled and the primary definitions are identified. This document also gives guidance for the selection of components falling into the scope of the European Pressure Equipment Directive (PED) 15 and used in the gas infrastructure. Apart from the issue of the consistency of the pressur
18、e definition in the standards, there is also the issue of the pressure rating of equipment and systems. Other classifications (e.g. PN or class) do not necessarily completely coincide with the classification as defined in the CEN/TC 234 standards. Concept of pressure conditions On one hand, three di
19、fferent sets of pressure conditions are to be considered: conditions during testing and commissioning (P1); conditions during exceptional operating circumstances (P2); conditions during normal operation (P3). where: P1 P2 P3The maximum pressure levels related to these conditions are the topic of the
20、 primary definitions. On the other hand, two other pressure conditions are used for specifying the system: pressure on which design calculations are based (pA); pressure rating of the system (pB). where pA pB.The relationship between pAand P2or P3is not uniform in the different CEN/TC 234 standards.
21、 This situation is confusing and undesirable. The recommended practice is stated in chapter 4.4 and 4.5 below and should be considered when revising standards or developing new standards. PD CEN/TR 16395:2012CEN/TR 16395:2012 (E) 5 Piping versus pressure regulating installations Only two out of the
22、three aforementioned conditions apply when specifying piping: conditions during testing and commissioning; operating conditions. Normally for piping no distinction is made between normal operating conditions and exceptional operating conditions, as piping is a passive component. However, in gas infr
23、astructure piping and pressure regulating installations both are present. This necessitates identification of the “normal operating conditions” and “exceptional operating conditions” of the pressure regulating installations and the “operating conditions” of the piping. PD CEN/TR 16395:2012CEN/TR 163
24、95:2012 (E) 6 1 Scope This Technical Report gives explanation on the pressure definitions used by the gas network operators with regard to the standards of CEN/TC 234 “Gas Infrastructure“. The European Standards of CEN/TC 234 comprise the functional requirements in the field of gas infrastructure fr
25、om the input of gas into the on-shore transmission network up to the inlet connection of gas appliances, including transmission, distribution, storage, compression, pressure regulation and metering, installation, injection of non-conventional gases, gas quality issues and others. 2 Normative referen
26、ces Not applicable. 3 Terms and definitions 3.1 Key pressure definitions used in CEN/TC 234 standards 3.1.1 design pressure DP pressure on which design calculations are based Note 1 to entry: A system designed for a design pressure (DP) can comprise components designed for a different maximum allowa
27、ble pressure (PS). 3.1.2 maximum operating pressure MOP maximum pressure at which a system can be operated continuously under normal operating conditions Note 1 to entry: Normal operating conditions are: no fault in any device or stream. Note 2 to entry: The set point of the regulator does not excee
28、d MOP. 3.1.3 maximum incidental pressure MIP maximum pressure which a system can experience during a short time, limited by the safety devices 3.2 Derived pressure definitions used in CEN/TC 234 standards 3.2.1 operating pressure OP nominal pressure on which the system is operated 3.2.2 temporary op
29、erating pressure TOP pressure at which a system can be operated temporarily under control of regulating devices PD CEN/TR 16395:2012CEN/TR 16395:2012 (E) 7 3.2.3 test pressure TP pressure at which pressure tests are conducted 3.2.4 strength test pressure STP pressure applied to a system during stren
30、gth testing 3.2.5 tightness test pressure TTP pressure applied to a system during tightness testing 3.2.6 combined test pressure CTP pressure applied to a system during combined testing, i.e. tightness and strength testing 3.3 Commonly used pressure definitions in European product standards 3.3.1 ma
31、ximum allowable pressure PS maximum pressure for which the equipment is designed, as specified by the manufacturer Note 1 to entry: Definition and requirements according Directive 97/23/EC (Pressure Equipment Directive - PED). 3.3.2 nominal pressure PN xx alphanumeric designation used for reference
32、purposes related to a combination of mechanical and dimensional characteristics of a component of a pipework system Note 1 to entry: It comprises the letters PN followed by a dimensionless number. SOURCE: EN 1333, modified 3.3.3 class xxx alphanumeric designation used for reference purposes related
33、to a combination of mechanical and dimensional characteristics of a component of a pipework system Note 1 to entry: It comprises the word “Class“ followed by a dimensionless whole number. SOURCE: EN 1759-1, modified 4 Explanation of Gas pressure definitions for gas transport and distribution systems
34、 4.1 General The pressure levels in the system MOP, TOP and MIP are to be chosen by the network operator when designing and operating its network according to its constraints and national regulations. PD CEN/TR 16395:2012CEN/TR 16395:2012 (E) 8 4.2 Pressure demarcation For a pipeline system, the max
35、imum pressure values will occur at the entrance of a pipeline section. However, in case the gas stream is interrupted for any reason, the whole pipeline section will be subjected to the same pressure level. The demarcation line for different pressure levels are, in the case of gas pressure regulatin
36、g stations, at the exit flange of the gas pressure regulator1)EN 12186 and for compressor stations, at the entrance of the compressor EN 12583. 4.3 Operating conditions 4.3.1 Normal operating conditions 4.3.1.1 MOP Maximum operating pressure The most relevant information related to the pressure in a
37、 network is the maximum pressure at which the system can be operated under normal conditions. This value is defined as the maximum operation pressure (MOP). The maximum set point of the operating pressure is MOP, considering the available accuracy classes and the lock-up pressure of gas pressure reg
38、ulators EN 334 or other regulating devices. The instantaneous pressure (peak level OP) in the system can be occasionally higher than MOP even under normal operating conditions. 4.3.1.2 OP Operating pressure OP is the pressure which occurs within a system under normal operating conditions, being the
39、set point of the pressure regulating system at the entry of a pipeline. 4.3.1.3 Peak level OP For pipelines with MOP 16 bar, the peak level OP is limited to 1,025 MOP EN 1594. For pipelines with a MOP up to and including 16 bars, no limit is given in EN 12007. However, for gas pressure regulating st
40、ations for transport and transmission and gas pressure regulating installations on service lines, the allowed limits for this peak level OP is given in EN 12186 and EN 12279; see Table 1. 4.3.2 Gas pressure under incidental operating conditions 4.3.2.1 General In case of a fault in the pressure regu
41、lator or compressor, the safety system will ensure that the pressure in the downstream system will not exceed a stated maximum value under any circumstance. 4.3.2.2 MIP Maximum incidental pressure The pressure value that may not be exceeded in the gas infrastructure, even under fault conditions, is
42、called MIP maximum incidental pressure. The pressure safety system has to ensure that MIP is never exceeded, also considering the dynamic behaviour of the system EN 12186. The accuracy class of the safety device is to be taken into account. 1) For details regarding the pressure demarcation in gas pr
43、essure regulating stations see EN 12186. PD CEN/TR 16395:2012CEN/TR 16395:2012 (E) 9 Figure 1 below illustrates the maximum set values for a possible pressure control system. Key AC: Accuracy class EN 334 SG: Lock-up pressure class EN 334 AG: Accuracy group EN 14382 Figure 1 Example: Pressure stagge
44、ring for a single stream pressure control system with a Safety shut-off device (SSD) and a monitor as safety devices NOTE Detailed information with regard to the calculation of pressure values from the parameters AC, SG and AG is given in EN 334 and EN 14382. 4.4 Design pressure Regarding the wall t
45、hickness calculations for systems of gas infrastructure, the design pressure is given in the related standards. This value can be derived from MOP, MIP or another value as stated in the aforesaid standards. Pipelines and systems have to be capable to withstand at least the MIP. The relation between
46、MIP and MOP depends on the pressure of the system as given in Clause 5. 4.5 Test pressures Test pressures (STP, CTP) are indicated Table 1. The requirements for the tightness test pressures are given in the relevant CEN/TC 234 standards. 4.6 Equipment in the scope of the European Pressure Equipment
47、Directive The design approach laid down in the PED considers only the maximum allowed pressure PS at which the equipment may be operated. To allow the operation of the equipment up to PS it is considered that the functional behaviour of the safety system may lead to a maximum overpressure of 1,1 PS.
48、 For standard pressure equipment used in the gas infrastructure the following condition shall be fulfilled: PD CEN/TR 16395:2012CEN/TR 16395:2012 (E) 10 1,1MIPPS NOTE 1 An additional tightness test for components designed under PED may be required according to the relevant standards. NOTE 2 In EN 15
49、001-1 DP is considered as equivalent to PS. NOTE 3 Information on industrial installations according EN 15001 is given in Annex B. In some countries MIP may be limited to PS of the standard pressure equipment according national regulations or standards. In this case standard pressure equipment for installation in the gas infrastructure has to be selected with PS MIP. 5 Relationships between MOP, TOP and MIP and test pressures The figures given in the following table are maximum values
