1、=- A CEN EN*ISO 42b7-2 95 3404589 0120359 22T BRITISH STANDARD Petroleum and liquid petroleum products - Calculation of oil quantities Part 2. Dynamic measurements The European Standard EN Is0 4267-2 : 1995 has the status of a British Standard BS EN IS0 4267-2 : 1996 IncOrpomt.ing Amendment No. 1 BS
2、 7286 Part 2 : 1990 YenU?lbered . . . ._.- . . _ . i-. I_ _ A CEN EN*ISO 4267-2 95 3404587 OL203b0 T4L EN IS0 4267-2 : 1996 Issue 2, March I996 Contents Page National foreword Inside front cover Committees responsible Back cover Method O Introduction 1 Scope and field of application 2 References 3 D
3、efinitions 4 Hierarchy of accuracies 5 Principal correction factors 6 Calculation of prover volume 7 Calculation of meter factor 8 Calculation of K-factor 9 Calculation of measurement tickets AninX A Correction factors for the effect of temperature and pressure on steel 1 1 1 2 2 2 5 11 19 20 22 TaM
4、st 1 Hierarchy of accuracies 2 Isothermal compressibility factor for water 3 Throughput calculations and corresponding meter factor calculations 4 Temperature correction factors for steel - Cts for mild steel having a cubical coefficient of expansion of 3.3 x 10-5/0C 5 Temperature correction factors
5、 for steel - C, for stainless steel having a cubical coefficient of expansion of 5.1 x IO-/ OC 6 Correction factors for effect of pressure on a mild steel prover 7 Correction factors for effect of pressure on a mild steel prover Page 3 4 12 22 22 23 24 National foreword This British Standard was pre
6、pared by PT1112 and is the English language version of EN IS0 4267-2 : 1995 Petroleum and liquid petroleum pducts - Calculation of oil quantities - Part 2 : Dynamic measurement published by the European Committee for Standardization (CEN). It is identical with IS0 4267-2 : 1988 published by the Inte
7、rnational Organisation for standardization (ISO). Cross-references International standard Corresponding British Standard IS0 91-1 : 1992 IS0 2715 : 1981 IS0 8222 : 1987 Additional information. With reference to 7.3 and 8.3, the employment of digital computers may mean that some users prefer to use a
8、ll available data without rounding. Agreement may therefore be reached between the parties concerned not to apply the rounding procedure described in 7.3 and 8.3 and applied throughout the standard. Agreement should then be reached on the number of significant figures to be applied (see also clause
9、O). Compliance with a British Standard does not of itself confer immunity from legal obligations. BS 6441 : 1993 Schedule Forpetmleum measurement tables BS 6169 Methods for volumetric measurement of liquid hydrucarbons Part 2 : 1984 Turbine meter systems BS 6922 : 1988 Specification for temperature
10、corrections for use in the calibration of reference measuring systems for pettvleum measurement A Original Original - CEN EN*ISO 4267-2 95 m 3404589 OL203bL 988 m Inside ,ac, cover Back cover A Issue 1, March 1996 BS 7286 : Part 2 : 1990 Summary of pages The following table identifies the current is
11、sue of each page. hue 1 indicates that a page has been introduced for the first time by amendment Subsequent issue numbers indicate an updated page. Vertical sidelining on replacement pages indicates the most recent changes (amendment, addition, deletion). Front cover Inside front cover a b EN cover
12、 page iib 1 2 3 4 5 6 7 8 9 10 Issue II Page 2 2 1 blank 1 1 0riglM.l Original Originai Original Original Original original original II 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Issue Onginai Original Original Original Original Originai Original Original original Original Originai Origrnai Origirlal
13、 original 2 2 Change of identifier Wherever BS 7286 : Part 2 : 1990 appears in this standard, it should be read as BS EN IS0 4267-2 : 1996. A CEN ENSISO 4267-2 95 3404589 0120362 814 W EN IS0 4267-2. October 1995 ICs 75.200 Descriptors: Petroleum products, hydrocarbons, liquefied petroleum gases, vo
14、lume measurement, rui= of calculation English version Petroleum and liqyid petroleum products - Calculation of oil quantities - Part 2: Dynamic measurement (IS0 4267-2 : 1988) Ptrole et produits ptroliers liquides - Calcul des quantits de ptrole - Partie 2: Mesurage Minerall und fltbsige Minerallerz
15、eugnisse - Berechnung von lmengen - Teil 2: Dynamische dynamique Messung (IS0 4267-2 : 1988) (IS0 4267-2 : 1988) This European Standard was approved by CEN on 19950909. CEN members are bound to comply with the CENKENELEC Internai Regulations which stipulate the conditions for giving this European St
16、andard the status of a national standard without any alteration. Up-to-date lists and bibliographid references concerning such national standards may be obtained on application to the Centrai Secretariat or to any CEN member. This European Standard exists in three officiai versions (English, French,
17、 German). A version in any other language made by translation under the responsibility of a CEN member into its own language and noed to the Central Secretariat has the same status as the officiai versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France,
18、Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netheriandis, Norway, Portuga, Spain, Sweden, Switzerland and United Kingdom. CEN European Commitee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1060 Brussels O 1995
19、AU rights of reproduction and communication in any form and by any means reserved in ali countries to CEN and its members Ref. No. EN IS0 4267-2 : 1995 E Page 2 A CEN EN*ISO 4267-2 95 3404589 OL203b3 750 Issue 1, March 1996 EN IS0 4267-2 : 1995 Foreword The text of the International Standard from IS
20、ORY: 28, Petroleum products and lubricants, of the intemationai Organization for Standar-on (iS0) has been taken over as a European Standard by the Technicai Commit either is possible. 4.1.2 To expect equal or less uncertainty at a lower levei of the hierarchy than exists in a higher level is unreal
21、istic. The only way to decrease the random component of uncertainty in a given measurement system or method is to increase the number of determinations, and calculate the mean value. The number of significant digits in intermediate calculations of a value can be larger in the upper levels of the hie
22、rarchy than in the lower levels. 4.2 Hierarchy 4.2.1 The hierarchy of accuracies in this standard is struc- tured, in general, as shown in table 1. 4.2.2 This standard gives rules for rounding, truncating and reporting final values for each level of the hierarchy. 5 Principal correction factors 5.1
23、Purpose and implications 5.1.1 Designation of correction factors by symbol rather than by words is recommended because, first, it abbreviates their expression; second, it allows algebraic manipulations; third, it indicates their similarity subject only to the particular liquid or metal involved; and
24、 fourth, it can more readily eliminate confu- sion, as for example the difference between the compressibility factor F of a liquid and the correction factor Co, which is a function of F. There are six principal correction factors employed in calcula- tions of liquid quantities. 5.1.2 The first of th
25、ese six correction factors is the meter fac- tor MF, a non-dimensional value which corrects the volume in- dicated on a meter or meter accessory to the actual volume, be that volume a raw or corrected volume (see clause 71. In some instances, the K-factor is used in place of or along with the meter
26、factor (see clause 8). 2 CEN ENMISO 42b7-2 75 W 3404589 0120366 4bT W IS0 4267-2 : 1988 (E) Correction factors and intermediate calculations to Hierarchy level Table 1 - Hierarchy of accuracies Temperature and pressure determination, for entering calculations, to Number of significant digits in volu
27、me Clause 6 7 8 9 0.05 oc 50 kP$) Prover I 6 decimal placesi) I 5 I calibration Meter factor 0,25 OC3) 50 kPP1 I 4decimal places I 5 I 0.25 oc31 50 kP$l K-factor I 4 decimal places 0,s oc31 I I 50 kP$) 4 decimal places I Measurement tickets I 1 I When water is used as the calibration liquid, correct
28、ion factors for the effect of temperature and pressure on the calibrating liquid to 6 decimal places are used. When a hydrocarbon is used as the calibrating liquid, correction factors for the effect of temperature and pressure on the calibrating liquid shall be calculated using the procedures referr
29、ed to in IC0 91-1. Factors calculated using IS0 91-1 will be limited to 5 significant figures (4 or 5 decimal places). Cases may anse where calibration personnel do not have the capability to calculate IS0 91-1 values but do have access to the printed tables referred to in IS0 91-1. Under these cond
30、itions, linear interpolation of the tables over a limited span is ac- ceptable for use in correcting for the temperature difference between master meter and prover during calibra- tion. 21 In all hierarchies above, pressures shall be read, recorded and rounded to the nearest 50 kPa (0,5 bar). Where
31、the gauge scale permits a closer tolerance, readings should be read, recorded and rounded to the nearest gauge scale division. 3) The use of a temperature determination device that can perform to a more stringent determination level than outlined in table 1 is acceptable provided that the installati
32、on, maintenance, operation and calibration practices are adequate to ensure performance to the level chosen. 5.1.3 The next four correction factors employed in calcula- tions of liquid quantities are needed because of changes in volume from the effects of temperature and pressure upon both the conta
33、ining vessel (usually made of mild steel) and upon the liquid involved. These four correction factors are: C, (or CTS) . the correction factor for the effect of temperature on steel (see 5.2) Cps (or CPS) . the correction factor for the effect of pressure on steel (see 5.3) Cpl (or CPL) . the correc
34、tion factor for the effect of pressure on liquid (see 5.4) C, (or CTLi . the correction factor for the effect of temperature on liquid (see 5.51 5.1.4 Finally, there is a correction factor C, (or CSW) for ac- counting for the presence of sediment and water in crude oil (see 9.3.1 l. 5.1.5 Additional
35、 subscripts may be added to the symbolic notations above to make it clear to what part of the measuring apparatus they apply, namely p for prover, m for meter and M for a volume standard measure. While the customary subscript notation is used in this standard, the allowed upper case notation is need
36、ed for computer pro- gramming and is convenient in typing. In such cases, M for measure shall be SM while m for meter shall be M. 5.1.6 The method for correcting volumes by 2 or more factors is to first obtain a CCF (combined correction factor) by multiplying the individual correction factors togeth
37、er in a set se- quence, rounding at each step. Only then multiply the volume by the CCF. The set sequence is MF, Crs, Cp: C, Cri and C, omitting any factors that may not be required in the calculation. NOTE - This is considered the theoretically correct sequence for ap- plying the six correction fac
38、tors. However, it is acknowledged that, in some cases where mechanical or electronic devices are used to apply one or more of these factors, the order may be changed. This is especially true of temperature-compensated meters. However, if the correction factors are determined using the correct basis
39、of temperature, pressure and density, the numerical value of the com- bined correction factor (CCF) will not be significantly different from the theoretical value. 5.1.7 All multiplication within a single operation shall be com- pleted before the division is started. 5.2 c, 5.2.1 The volume of a met
40、al container, such as a pipe prover, tank prover or volume standard measure, will change when subjected to a change in temperature. The volume change, regardless of shape, is directly proportional to the temperature 3 CEN EN+ISO 4267-2 IS0 4267-2 : 1988 (E) change of the material of which the contai
41、ner is made. The cor- rection factor for the effect of temperature on steel iC,) shall be calculated from the equation where t is the temperature, in degrees Celsius, of the container walls: y is the coefficient of cubical expansion per degree Celsius of the material of which the container is made.
42、Thus, C, will be greater than 1 when the temperature I is greater than 15 OC, and less than 1 when the temperature I is less than 15 OC. 5.2.2 The value of y is 3,3 x (or 0,OOO 033) per degree Celsius for mild or low-carbon steels, and has a range of 4,30 x to 5,40 x per degree Celsius for Series 30
43、0 stainless steels. The value used in the calculations shall be that given on the certificate from the calibrating agency for a volume standard measure or from the manufacturer of a pro- ver. Tables of C, values against observed temperature will be found in annex A of this standard, the table for st
44、ainless steels being based upon a typical value of y of 5.10 x for Series 300 stainless steels. 5.2.3 When the volume of the container at standard temperature (15 OC) is known, the volume at any other temperature t can be calculated from the equation 5 = v,5 x c, . . . (2) 5.2.4 Conversely, when the
45、 volume of the container at any temperature t is known, the volume at standard temperature (15 OC) can be calculated from the equation 5.3 c, 5.3.1 If a metal container such as a tank prover, pipe prover or volume standard measure is subjected to an internal pressure, the walls of the container will
46、 stretch elastically and the volume of the container will change accordingly. While it is recognized that simplifying assumptions enter the equations below, for practical purposes the correction factor Cp for the effect of internal pressure on the volume of a cylin- drical container shall be calcula
47、ted from the equation C, = 1 + PDIET . . . (4) where P is the internal gauge pressure in kilopascals; D is the internal diameter in millimetres; 95 3404589 03203b7 3Tb = E is the modulus of elasticity of the container material (2.1 x 108 kPa for mild steel and 1,9 x 108kPa to 2,O x 108 kPa for stain
48、less steels); T is the wall thickness of the container in millimetres. 5.3.2 C, values for specific sizes and wall thicknesses of mild-steel pipe provers and pressures may be found in tables 6 and 7 of annex A of this International Standard. When the volume of the container at atmospheric pressure V
49、at,s (.e. zero gauge pressure) is known, the container volume at any other pressure V, can be calculated from the equation 5.3.3 When the container volume at any gauge pressure P is known, the equivalent container volume at atmospheric pressure V, can be calculated from the equation 5.4 c, 5.4.1 The volume of a liquid is inversely proportional to the pressure acting on that liquid. The correction factor Cpl for the effect of pressure on a volume of liquid can be calculated from the equation 1 c- -l-(P-P,)F where P is the gauge pre
