BS ISO 8310-2012 Refrigerated hydrocarbon and non-petroleum based liquefied gaseous fuels General requirements for automatic tank thermometers on board marine carriers and.pdf

1、raising standards worldwide NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BSI Standards Publication BS ISO 8310:2012 Refrigerated hydrocarbon and non-petroleum based liquefied gaseous fuels General requirements for automatic tank thermometers on board marine carriers and flo

2、ating storageBS ISO 8310:2012 BRITISH STANDARD National foreword This British Standard is the UK implementation of ISO 8310:2012. It supersedes BS 7575:1992 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee PTI/12, Petroleum Measurement and Sampling. A

3、list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2012. Published by BSI Standa

4、rds Limited 2012 ISBN 978 0 580 75083 0 ICS 75.180.30 Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 November 2012. Amendments issued since publication Date

5、 T e x t a f f e c t e dBS ISO 8310:2012 ISO 2012 Refrigerated hydrocarbon and non- petroleum based liquefied gaseous fuels General requirements for automatic tank thermometers on board marine carriers and floating storage Hydrocarbures rfrigrs et combustibles gazeux liqufis base non ptrolire Exigen

6、ces gnrales pour les thermomtres de rservoir automatiques bord des transporteurs de cargaison en mer et des stocks flottants INTERNATIONAL STANDARD ISO 8310 Second edition 2012-11-01 Reference number ISO 8310:2012(E)BS ISO 8310:2012ISO 8310:2012(E)ii ISO 2012 All rights reserved COPYRIGHT PROTECTED

7、DOCUMENT ISO 2012 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member

8、body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in SwitzerlandBS ISO 8310:2012ISO 8310:2012(E) ISO 2012 All rights reserved iii Contents Page Foreword iv Introd

9、uction v 1 Scope . 1 2 Normative references 1 3 Terms and definitions . 1 4 Safety precautions 2 4.1 General . 2 4.2 Equipment precautions . 3 5 Design requirements 3 5.1 General . 3 5.2 Temperature sensors . 3 5.3 Indicating device . 4 5.4 Installation 4 5.5 Provisions for routine maintenance and v

10、erification 4 5.6 Provision against sudden malfunctions 4 5.7 Dynamic response 4 5.8 Measurable range . 4 5.9 Data processing and reporting 4 5.10 Compensation for variation of cargo temperatures 5 5.11 Sealing, security and unsealing . 5 5.12 Redundancy . 5 5.13 Data communication 5 6 Calibration a

11、nd accuracy verification 5 6.1 General . 5 6.2 Calibration reference . 6 6.3 Calibration and accuracy verification at factory 6 6.4 Calibration and accuracy verification after installation 6 6.5 Periodic accuracy verification 9 7 Accuracy requirement 9 7.1 Overall error 9 7.2 Resolution 10 8 ATT cal

12、ibration records .10 Annex A (informative) Information on platinum resistance thermometers .11 Bibliography .12BS ISO 8310:2012ISO 8310:2012(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of pr

13、eparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, i

14、n liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main tas

15、k of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attentio

16、n is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 8310 was prepared by Technical Committee ISO/TC 28, Petroleum products and lubricants, Subcommittee SC 5,

17、 Measurement of refrigerated hydrocarbon and non-petroleum based liquefied gaseous fuels. This second edition cancels and replaces the first edition (ISO 8310:1991), which has been technically revised.iv ISO 2012 All rights reservedBS ISO 8310:2012ISO 8310:2012(E) Introduction Large quantities of li

18、quefied natural gas (LNG), liquefied petroleum gas (LPG) and other liquefied gases are usually transported by marine carriers dedicated for these applications and traded based on static measurement on board by automatic tank measurement. Such an automatic tank measurement may be a part of the custod

19、y transfer measurement system (CTMS) which involves determination of liquid/vapour interface, i.e. liquid level, average temperatures of liquid and vapour, and vapour pressure. The volumetric quantity of the liquid and gas is then computed with the tank capacity table based on which the delivered qu

20、antity in terms of energy content or mass is calculated. In most cases, shore tank measurement is not used due to the active and dynamic conditions of the shore tank operations. In the absence of other means of acceptable measurement, custody transfer measurement usually takes place on board the car

21、rier or floating production storage offshore (FPSO) and floating storage offshore (FSO). Liquid cargo density is very sensitive to temperature; therefore, obtaining accurate temperature readings is extremely important. For example, a change of 0,2 C for liquid methane cargo results in a change in de

22、nsity of approximately 0,07 %. This International Standard also discusses use of automatic tank thermometers on board marine vessels for other volatile, non-petroleum liquids in fully refrigerated conditions. Many of these non-petroleum liquids, such as di-methyl ether (DME) are measured in a simila

23、r manner to that used for fully refrigerated LPGs. Values of temperature in this International Standard are in terms of the International Temperature Scale of 1990, ITS-90. Temperatures in degrees Celsius are denoted by the symbol t. ISO 2012 All rights reserved vBS ISO 8310:2012BS ISO 8310:2012Refr

24、igerated hydrocarbon and non-petroleum based liquefied gaseous fuels General requirements for automatic tank thermometers on board marine carriers and floating storage 1 Scope This International Standard specifies the essential requirements and verification procedures for automatic tank thermometers

25、 (ATTs) consisting of platinum resistance thermometers (PRT) and an indicating device used for custody transfer measurement of liquefied natural gas, liquefied petroleum and chemical gases on board ships. Temperature detectors other than PRT are considered acceptable for use in the custody transfer

26、service of liquefied gases if they meet the performance requirements of this International Standard and are approved by national regulations. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. Fo

27、r dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60751, Industrial platinum resistance thermometers and platinum temperature sensors 3 Terms and definitions For the purposes of this docum

28、ent, the following terms and definitions apply. 3.1 automatic tank gauge ATG automatic level gauge ALG instrument that automatically measures and displays liquid levels or ullages in one or more tanks, either continuously, periodically or on demand 3.2 automatic tank gauging system ATG system system

29、 that includes ATGs at the cargo tanks and control/display unit that processes and displays output signals from the ATG along with any other parameters required to determine the liquid level, i.e. liquid/vapour interface 3.3 automatic tank thermometer ATT automatic tank temperature system instrument

30、 that continuously measures temperature in cargo tanks NOTE 1 An ATT typically includes temperature sensors, such as PRTs, field-mounted transmitters for electronic signal transmission, and indicating device(s). NOTE 2 ATTs on liquefied gas carriers are usually multiple-point ATTs which consist of t

31、hree or more temperature sensors, such as PRTs, to measure the temperatures at selected heights in the cargo tank. INTERNATIONAL ST ANDARD ISO 8310:2012(E) ISO 2012 All rights reserved 1BS ISO 8310:2012ISO 8310:2012(E) 3.4 custody transfer measurement system CTMS system that processes inputs from an

32、 ATG system, an ATT, pressure gauges, etc. and provides custody transfer measurement information on board, generating documents with regard to custody transfer of liquefied gases NOTE An ATT can be incorporated as part of a CTMS. 3.5 gas dangerous space or zone space or zone defined by the Internati

33、onal Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code) 3.6 indicating device displaying device set of components of a measuring instrument intended to indicate the measured value 3.7 inherent error intrinsic error error of a gauge when it is tested against

34、a reference standard under controlled conditions as specified by the manufacturer 3.8 nominal resistance expected resistance R 0of a PRT at 0 C, declared by the manufacturer and shown in the thermometer marking, usually rounded to the nearest ohm 3.9 nominal temperature/resistance relationship relat

35、ionship between temperature and resistance of a nominal PRT 3.10 platinum resistance thermometer PRT resistance temperature detector RTD temperature-responsive device consisting of one or more sensing platinum resistors within a protective sheath, internal connecting wires and external terminals to

36、permit connection of electrical measurement instruments 3.11 uncertainty non-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand, based on the information used 4 Safety precautions 4.1 General Nothing contained in this International Standard is int

37、ended to supersede any regulatory requirements or recommended operating practices issued by organizations such as the International Maritime Organization (IMO), International Chamber of Shipping (ICS), Oil Companies International Marine Forum (OCIMF), International Association of Classification Soci

38、eties (IACS) and individual operating companies, nor is this International Standard intended to conflict with any safety or environmental considerations, local regulations, or the specific provisions of any contract.2 ISO 2012 All rights reservedBS ISO 8310:2012ISO 8310:2012(E) 4.2 Equipment precaut

39、ions 4.2.1 General All electric components of an ATT for use in electrically classified areas shall meet the electrical area classification. They shall conform to applicable sections of the national and/or international electrical safety standards. All ATTs shall be maintained in a safe operating co

40、ndition and manufacturers maintenance instructions should be complied with. 4.2.2 Mechanical rigidity All ATTs shall be capable of withstanding the pressure, temperature, dynamic loads generated from rolling/pitching, and sloshing from environmental conditions likely to be encountered in the service

41、. Where a PRT is installed near a submerged pump or the end of a loading/unloading line in a cargo tank, appropriate measures shall be applied to prevent the ATT from being affected by the vortex or vaporization, i.e. boiling, of cargo caused by cargo loading or cargo unloading operations. In additi

42、on, all PRTs shall be mounted such that they are not affected by the spray of liquefied gas whenever the spray nozzles are in operation. 4.2.3 Gastight design All parts of ATTs exposed to a gas dangerous space or zone shall be of gastight construction. 4.2.4 Compatibility with cargo All parts of the

43、 ATT in contact with liquefied gases or their vapour shall be chemically compatible with the product, to avoid both product contamination and corrosion of the ATT. 4.2.5 Tolerance against low temperatures ATTs shall be designed to measure the low temperatures encountered in refrigerated liquefied ga

44、s service. They shall also be designed to withstand the low-temperature thermal contraction of their components and of the tanks. Additionally, change in the height of PRT in the tanks by such thermal contraction shall be compensated for in an appropriate manner. 4.2.6 Type approval The design and i

45、nstallation of ATTs shall be subject to the approval of a national metrology institute (NMI) or class society. For electrical considerations, refer to IACS Unified Requirements E10 10 . Type approval is normally issued after an ATT has been subjected to a specific series of tests. 5 Design requireme

46、nts 5.1 General The following design requirements apply to all types of ATTs on liquefied gas carriers, FPSOs and FSOs. These requirements, which may be in addition to the technical specifications by the ATT manufacturer, should be met where they are applicable. 5.2 Temperature sensors Temperature s

47、ensors used for custody transfer measurement of liquefied gases on board ships shall be either three- or four-wire type PRTs as described in IEC 60751. The relationship of temperature and resistance of the PRTs is described by a temperature/resistance relationship (see Annex A). ISO 2012 All rights

48、reserved 3BS ISO 8310:2012ISO 8310:2012(E) Each PRT shall be subject to the following routine production tests: a) insulation resistance at ambient temperature; b) sheath integrity test; c) dimensional test; d) tolerance acceptance test. NOTE See IEC 60751 for the details of the routine production t

49、est. The manufacturer shall calibrate each PRT and establish its nominal resistance (R 0 ) and constants A, B and C in the temperature/resistance relationship. Identification such as the serial number should be clearly and indelibly marked on each PRT. 5.3 Indicating device Indicating devices with analogue inputs shall have a high-impedance input circuit so as to minimize error. 5.4 Installation The number of PRTs in a tank depends on the capacity and the height of the tank; however, IGC Code requires a minimum of three. In the c