1、DEUTSCHE NORM December 2000 Welded static non-pressurized thermoplastic tanks Part 4: Design and calculation of flanged joints English version of DIN EN 12573-4 DIN - EN 12573-4 ICs 23.020.1 O; 23.040.60 Geschweite ortsfeste drucklose Behlter (Tanks) ausThermoplasten -Teil 4: Konstruktion und Berech
2、nung von Flanschverbindungen European Standard EN 12573-4 : 2000 has the status of a DIN Standard. A comma is used as the decimal marker. National foreword This standard has been prepared by CEN/TC 266 Thermoplastic static tanks, WG 2 Thermoplastic tanks fabricated by fusion techniques. The responsi
3、ble German body involved in its preparation was the Normenausschuss Tankanlagen (Tank Installations Standards Committee), Technical Committee Tanks aus Thermoplasten. EN comprises 14 pages. No pari of this standard may be reproduced without the prior permission of Ref. No. DIN EN 12573-4 : 2000-1 Y
4、Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany, s the exclusive right of sale for German Standards (DIN-Normen). English price group 08 Sales No. 1108 05.01 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12573-4 March 2000 ICs 23.020.10; 23.040.60 English
5、 version Welded static non-pressurized thermoplastic tanks Part 4: Design and calculation of flanged joints Cuves statiques soudes en matires thermoplastiques sans pression - Partie 4: Conception et calcul des joints brides von Flanschverbindungen Geschweite ortsfeste drucklose Behlter (Tanks) aus T
6、hermoplasten - Teil 4: Konstruktion und Berechnung This European Standard was approved by CEN on 2000-02-14. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterat
7、ion. Up-to-date lists and bibliographical references concerning such national stand- ards may be obtained on application to the Central Secretariat or to any CEN member. The European Standards exist in three official versions (English, French, German). A version in any other language made by transla
8、tion under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, the Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland
9、, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, and the United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels O 2000. CEN - All rights of ex
10、ploitation in any form and by any means reserved worldwide for CEN national members. Ref. No. EN 12573-4 : 2000 E Page 2 EN 12573-4 : 2000 Contents Page Foreword 3 1 Scope . 3 2 Normative references 3 3 Symbols and abbreviations . 3 4 Design requirements . 4 4.1 General . 4 4.2 Design principles . 6
11、 5 Calculation of the properties of bolts . 6 5.1 General . 6 5.2 Calculation of the bolt forces in the case of continuous gaskets . 6 5.3 Calculation of the bolt forces in the case of O-ring gaskets 7 6 Calculation of the flange thickness . 8 6.1 General . 8 6.2 Fusion welded, moulded full face fla
12、nges and welded-on full face flanges with a continuous gasket or with an O-ring gasket 9 6.3 Fusion welded stub flanges and welded-on stub flanges with continuous gasket or with an O-ring gasket 10 7 Calculation of loose metal backing rings 11 Annex A (normative) Material parameters for loose metal
13、backing rings 12 Annex B (informative) A-deviations . . 13 Bibliography . 14 Page 3 EN 12573-4 : 2000 Foreword This European Standard has been prepared by Technical Committee CENTTC 266 “Thermoplastic static tanks“, the secretariat of which is held by BSI. This European Standard shall be given the s
14、tatus of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2000, and conflicting national standards shall be withdrawn at the latest by September 2000. prEN 12573:1999 “Welded static non-precsurised thermoplastic tanks“ consists of: Part 1
15、: General principles Part 2: Calculation of vertical cylindrical tanks Part 3: Design and calculation of single skin rectangular tanks Part 4: Design and calculation of flanged joints The normative annex A gives the values for the calculation of loose metal backing rings According to the CENKENELEC
16、Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Noway, Portugal, Spain, Sweden, Switzerl
17、and and the United Kingdom. 1 Scope This part of this standard specifies the design and calculation of circular flanged joints, fabricated in the following thermoplastics: Polyethylene (PE) Polypropylene (PP) Poly (vinyl chloride) (PVC) Poly (vinylidene fluoride) (PVDF) 2 Normative references This E
18、uropean Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publicati
19、ons apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. prEN I 2573-1 :I 999 Welded static non-pressurised thermoplastic tanks - Part 1 : General principles EN 1778 Characteristic val
20、ues for welded thermoplastic constructions - Determination of allowable stresses and moduli for design of thermoplastic equipment 3 Symbols and abbreviations For the purposes of this part of this Standard the following symbols and abbreviations apply: Ai AZK a b bD C, C do is the reduction factor to
21、 take account of the effect of specific strength, see EN 1778 is the reduction factor taking into account the effect of surrounding medium, see EN 1778 is the depth of the weld seam, in millimetre is the effective double flange width, in millimetre is the gasket width, in millimetre are welding proc
22、ess constants is the corrosion allowance, in millimetre is the gasket mean diameter, in millimetre Page 4 EN 12573-4 dK dL dL da di di di dz d3 fi hD hF K K KD KW KWlr ko ki h I n PDV PFI PSB PSB PSO P P S SU SIM t w1, w2, w3 YI, Y2 V CY 2000 is the bolt shank diameter, in millirnetre is the bolt ho
23、le diameter, in millimetre is the reduced bolt hole diameter, in millimetre is the outside diameter of flange, in millimetre is the inside diameter of cylindrical components, in millimetre is the pitch circle diameter, in millimetre is the inside diameter of loose backing ring, in millimetre is the
24、mean contact diameter of a flange or stub flange, in millimetre is the dl + 2 x flange edge radius, in millirnetre, see figure 15 is the depth of the weld undercut, in millirnetre is the gasket thickness, in millimetre is the required thickness of a flange plate, in millimetre is the creep strength
25、at the design temperature and lifetime, in newton per square millimetre, see EN 1778 is the creep strength at a test condition (temperature and time), in newton per square millimetre is the deformation resistance of gasket material, in newton per square rnillimetre is the allowable yield stress of l
26、oose backing ring material (metal), in newton per square millimetre is the allowable yield stress of bolt material, in newton per square millimetre is the characteristic value of a gasket in the assembled condition, in millimetre is the characteristic value of a gasket in the operating condition, in
27、 millimetre is the flange neck height, in miliimetre is the lever arm of bolt force, in millimetre is the number of bolts is the assembly force, in newton is the surface pressure, in newton per square millimetre is the bolt force in operating condition, in newton is the bolt force at test pressure,
28、in newton is the bolt force in assembled condition prior to application of pressure, in newton is the operating pressure above atmospheric, in bar is the test pressure, in bar is the safety factor, see part 1 is the safety factor for metals in operating condition is the safety factor for metals in t
29、est and assembled condition is the wall thickness of cylindrical component, in mm is the weakening coefficient are the moments of resistance of the flange, in cubic millirnetre is the lever arm of the forces acting on the O-ring, in millimetre is the angle, in degrees 4 Design requirements 4.1 Gener
30、al Various types of flanges are characterized by their shapes as shown in figure 1 to 4: Figure 1 : Fusion weld, moulded full face flange Figure 2: Fusion welded stub flange Page 5 EN 12573-4 : 2000 Figure 3: Welded-on full face flange Figure 4 Welded-on stub flange Ali these flange joints shall be
31、designed with a continuous gasket or O-ring, see figures 5 to 10: Figure 5: Full face flanges with continuous gasket t Il t ti 1 t IA Figure 7:Stub flanges with continuous gasket Figure 9: Full face flange and loose metal backing ring Figure 6: Full face flanges with O-ring Figure 8: Stub flanges wi
32、th O-ring Figure 1 O: Full face flange and loose metal backing Page 6 EN 12573-4 : 2000 4.2 Design principles The number of bolts shall be chosen as large as possible, so that a uniform seal can be ensured. The number of bolts shall be at least four. The bolt spacing in thermoplastic flanges shall n
33、ot exceed 5 dL and shall not be greater than 80 mm. At low pressures the calculation can produce a flange thickness which is so small that the flanges can be deformed by the bolts forces. When positioned in the side wall of a tank below lhe liquid level, all flanges shall be reinforced with a loose
34、backing ring (e. g. GRP or steel), see figure 9 and 10. NOTE 1 : For design examples see 2 of Bibliography. NOTE 2: When selecting the gasket material, the thermal and chemical resistance should be considered carefully. Gaskets of soft material are preferred. 5 Calculation of the properties of bolts
35、 5.1 General The inside diameter of the thread of the steel bolt shall be the largest value calculated from equation (1) or (2): a) for the operating condition bl for the assembled condition where: Z = 1.75 for steel bolts, with known allowable yield stress, where p I 1,3 p c=3mm External forces, e.
36、 g. due to thermal expansion, are not taken into account in equations (1) and (2). 5.2 Calculation of the boit forces in the case of continuous gaskets 5.2.1 Operating condition The boll force in the operating condition shall be calculated according to equation (3). + 378 do . ki P -(- p n.dd:, sB-l
37、o 4 Page 7 EN 12573-4 : 2000 5.2.2 Assembled condition The bolt force in assembled condition shall be calculated according to equation (4). If PSO becomes greater than PSB, then PSO shall be calculated according to equation (5). The gasket parameters kl and ko . KD shall be taken from table 1. 5.3 C
38、alculation of the bolt forces in the case of O-ring gaskets 5.3.1 Flanges with O-ring gasket The bolt force in the operating condition for flanges with O-ring gaskets, see figure 11, shall be calculated according to equation (6). Figure 11: Flange with O-ring gasket 5.3.2 Stub flanges with O-ring ga
39、sket The bolt force in the operating condition for stub flanges with O-ring gaskets, see figure 12, shall be calculated according to equation (7). Figure 12: Stub flange with O-ring gasket Page 8 EN 12573-4 : 2000 Table 1: Gasket parameters for liquids, gases and vapours Gasket type) with hole witho
40、ut hole Material Rubber PTFE3) Gasket parameters) for li k,. KD N/mm lids kr mm for gases and vapours k,. KD N/mm 2, Apply to machined and undamaged sealing faces and depend on the hardness of the gasket material being lower than that of the flange material. ) Polytetrafluoroethylene 25 bo ki mm 0.5
41、 bD ) For flanges with a continuous gasket the effective gasket width becomes 0,5 bo. 6 Calculation of the flange thickness 6.1 General General principles for the calculation of thermoplastic flange thickness are given in prEN 12573-1 : 1999. The design of the flanges is determined by the greatest f
42、lange resistance required. For the operating condition the flange resistance shall be calculated according to equation (8). Page 9 EN 12573-4 : 2000 For the test condition the flange resistance shall be calculated according to equation (9). PSB . Ai . s , w2= K (9) For the assembled condition WJ is
43、not relevant. The values for K, K, AI, AZK and S are given in EN 1778. 6.2 Fusion welded, moulded full face flanges and welded-on full face flanges with a continuous gasket or with an O-ring gasket The lever arm of the bolt force for operating and test condition, see figures 13 and 14 , shall be cal
44、culated according to equation (1 O). dt di - t 2 1= For the assembled condition the lever am of the bolt force is zero. di _I Figure 13 : Fusion welded, moulded full face Figure 14:Welded-on full face flange flange (shown without gasket) (shown without gasket) The required height of the flange plate
45、 shall be calculated according to equation (1 1). where W is the largest of W, or W2 . For fusion welded, moulded full face flanges: C = 0,9; CI = 2 For welded-on full face flanges: C = 1 ,I ; CI = 3 Page 10 EN 12573-4 : 2000 6.3 Fusion welded stub flanges and welded-on stub flanges with continuous
46、gasket or with an O-ring gasket The lever arm of the bolt force for operating and test condition, see figures 15 and 16, shall be calculated according to equation (12). d2-di-t ri 1= L For the assembled condition the lever am of the bolt force is zero. Figure 15Fusion welded stub flange (shown witho
47、ut gasket) Figure 16:Welded-on stub flange (shown without gasket) The required height of the stub flange shall be calculated according to equation (1 3). where W is the largest of WI or WZ. For fusion welded stub flanges: C = 0.9; CI = 2 For welded-on stub flanges: C = 1,l; CI = 3 The surface pressu
48、re between loose backing ring and stub flange shall be calculated and assessed according to equations (1 4) and (1 5). Page 11 EN 12573-4 : 2000 7 Calculation of loose metal backing rings The design of the flange, see figure 17, is determined by the greatest required flange resistance WI, W2 or W3.
49、For the operating condition the flange resistance WI shall be calculated according to equation (1 6). For the test condition the flange resistance W2 shall be calculated according to equation (17). PSB . SM , 1 w2 = KFl I I ;f I A 3. Figure 17: Loose metal backing ring For the assembled condition the flange resistance WB shall be calculated according to equation (18). If Pso is greater than PsS, the value for PSO shall to be substituted for PSB in equation (16). Equation (18) is then not required. The values for KFI and SM and SIM shall be taken from ann
