《ASME 开孔补强计算.docx》由会员分享，可在线阅读，更多相关《ASME 开孔补强计算.docx（15页珍藏版）》请在taowenge.com淘文阁网|工程机械CAD图纸|机械工程制图|CAD装配图下载|SolidWorks_CaTia_CAD_UG_PROE_设计图分享下载上搜索。
1、PROJECTTITLE :Calculation of Shells with Openings according toAD-2000-Merkblattand ASME - CodePage 1 of 14 PagesStatusIssueDateDescriptionPagesPreparedCheckedApprovedProject No.:Project Code:Linde Document No:Issue: 01Page 10 of 14Wallthickness=100 mm5,59% 5,49% 5,39% 5,30% 5,21%5,12% 5,03% 4,95% 4,
2、87% 4,79% 4,71% 4,64% 4,57% 4,50% 4,44% 4,37% 4,31% 4,25% 4,19% 4,13% 4,07% 4,02% 3,97% 3,91% 3,86% 3,81% 3,77% 3,72% 3,67% 3,63% 3,59% 3,54% 3,50% 3,46% 3,42% 3,38% 3,35% 3,31% 3,27% 3,24% 3,20% 3,17% 3,14% 3,10% 3,07% 3,04% 3,00%3,00%Project No.:Project Code:Linde Document No:Issue: 01Page 11 of 1
3、46 Proceeding according to ASME, UG-37The regulations concerning the calculation of openings in cylindrical, conical and spherical shells are to be found in part UG-37 of the ASME Code, Section VIII, Division 1. The design for openings with and without reinforcing pads has to be performed according
4、to UG-37(a):A + A3 + A43 + 5 - A(1)The respective areas for the calculation of the opening can be seen in the following picture:PART UG GENERAL REQUIREMENTSFig. UG-37.1dtrF+2tntrF(1-frg r-FQ _ 2tn (Eyt-Ftr) (1 - %)尸 _2S(Et- 尸 )(1T一d or R + t + fn nUse larger valueSee UG-40 for limits of reinforcemen
5、tGENERAL NOTE:Includes consideration of these areas ifSn/Sv 人If Ay +42 + 3 + 反41 + 人42 + 幺43 + 25 人Opening is adequately reinforcedProject No.:Project Code:Linde Document No:Issue: 01Page 12 of 14In the first step, using the minimum required wall thickness and the nozzle wall thickness as well as a
6、possible reinforcing pad, the opening is dimensioned in such a way as to exactly satisfy equation ，ie(2)Ai + A? + & + 川 + A42 + A43 + & A.In the next step the required margin of safety f?for the corroded shell wall thickness T(including a possible reinforcing pad thickness) is determined according t
7、o the table. Subsequently, the shell wall thickness or the reinforcing pad thickness respectively (but not the nozzle thickness) have to be increased respectively in order to obtain the margin of safety in the opening under consideration. The existence of the required margin of safety has to be veri
8、fied with the increased wall thickness as follows:A1 + 42 + 43 + 人41 + A42 + 入43 + A + R100As a last step it is necessary to perform an as built calculation and to show the actual available margin of safety.For openings with a reinforcing pad, the following conditions have to be regarded: andDp 2 c/
9、 + 6.(，+ G).7 ExamplesIn the following two exemplary calculations are shown. The calculation can also be performed by means of commercial software. It only has to be made sure that the software clearly shows the required margin of safety. If this is not the case, an add-on displaying the calculated
10、margin of safety for the chosen geometry has to be provided.Without reinforcing pad:Ai =106 mm2 A2 = 8068 mm2 A = 8174 mm2Ss = 137,8 N/mm2 Sn = 137.8 N/mm2 p =21 bar t = 26.0 mm tr =22.71 mm tn = 77.0 mm tm = 3.84 mm d = 360 mm Di = 2954 mm a= 0.0 mmc= 3.0 mmFrom this, equation (2) follows as:106 +
11、8068 1x 18174Project No.:Project Code:Linde Document No:Page 13 of 14Issue: 01The terms A3j A41, A42, A43 and A5 are not applied because the nozzle is not inserted, the weld areas are not taken into consideration and a reinforcing pad does not exist.According to the table, a margin of safety of 13.2
12、9% has to be available for a T(corroded shell wall thickness) of 23.0 mm (T = t- a- c= 26.0- 0.0- 3.0 = 23.0 mm). Therefore, t is increased to 28 mm. A/, A2 und A are recalculated with the new hAi = 826 mm2 A2 = 8769 mm2A = 8174 mm2From this, equation (3) follows as:826 + 87698174= 1.1741.133It coul
13、d be shown that a margin of safety of 17.4% - which is higher than the required value of 13.29% - is available.It could be shown that a margin of safety of 17.4% - which is higher than the required value of 13.29% - is available.Since the example is a matter of a fictive geometry, an as built calcul
14、ation is not carried out.With reinforcing pad:Ss = 117.9 N/mm2Sn = 117,9 N/mm2p = 35 bar=30.0 mm=29.34 mm=23.0 mm=5.96 mm=25.0 mm=800 mm=360 mm=1940 mm=0.0 mmAi = 238 mm2A2 = 2557 mm2As = 7850 mm2A = 10562 mm2c = 0.0 mmFrom this, equation (2) follows as:238 + 2557 + 785010562The terms A3, A41, A42,
15、and A43 are not applied because the nozzle is not inserted and the weld areas are not taken into consideration.According to the table, a margin of safety of 5.49% has to be available for a T (corroded shell wall thickness + uncorroded reinforcing pad thickness) of 55 mm (T=t + te-a-c= 550 0.0- 0,0 =
16、 550 mm). Therefore, te is increased to 27 mm. A2, and /4are recalculated with the new teAi = 238 mm2A? = 2557 mm2As = 8478 mm2A = 10562 mm2Project No.:Project Code:Linde Document No:Issue: 01Page 14 of 14From this, equation (3) follows as:238 + 2557 + 847810562= 1.067 1.055It could be shown that a
17、margin of safety of 6.7% - which is higher than the required value of 5.49% - is available.Since the example is a matter of a fictive geometry, an as built calculation is not carried out.8 NotesThe following notes are to be considered when designing openings according to the aboveillustrated proceed
18、ing:The margin of safety may only be available in the shell (+ the possible reinforcing pad), i.e. it is not permitted to increase the nozzle wall thickness in order to obtain the necessary margin of safety.In case there is a reinforcing pad 7is composed of the corroded shell wall thickness and the
19、uncorroded reinforcing pad thickness.It is absolutely necessary to carry out the first step providing a margin of safety of 0% in order to provide the margin of safety only in the shell (+ reinforcing pad) in the second step.- The results of all the calculation steps have to be documented for the pu
20、rpose of checking.- It has to be clearly stated on the vessel drawing that the nozzle load analysis has been performed based on Lindes own method providing a margin of safety for the stresses.- In special cases (depending on the pressure, temperature, material or the nominal diameter) Linde will cal
21、culate the actual external loads (forces and moments) for specific nozzles. The loads result from a piping stress analysis based on the actual piping isometry. Linde will provide the vessel manufacturer with these external loads.The dimensioning of the openings as well as the stress analysis then ha
22、ve to be performed according to the code and WRCB 107 or PD 5500 (or with the help of the Finite Elements Method).Under the above mentioned circumstances, the requirements concerning the margin of safety according to points 1 to 3 of this document are not to be applied.Project No.:Project Code:Linde
23、 Document No:Issue: 01Page 2 of 14ContentsAD - 2000 - Merkblatt1 Fundamentals3Proceedingaccording to AD-B952 Examples6Notes8ASME - Code9Fundamentals93 Proceedingaccording to ASME, UG-3711Examples124 Notes14Project No.:Project Code:Linde Document No:Issue: 01Page 3 of 14AD - 2000 - MerkblattFundament
24、alsThe nozzles of a pressure vessel not only have to withstand an internal pressure loading but also additional loading resulting from the pipework (external loads). The external loads are usually only known at a later point during the processing of the project. Therefore, a margin of safety has to
25、be provided when designing the opening under internal pressure loading, in order to cover the stresses resulting from the external loads. This margin of safety has to be taken into account during the dimensioning of the shell.The design of openings under internal pressure loading has to be performed
26、 according to the following rules for the margin of safety:R = 62 %for T 6mm and T 100 mmT = corroded shell wall thickness including any existing reinforcing pad thicknessR = margin of safety at opening in %The margin of safety may only be provided in the shell, including a possible reinforcing pad.
27、 It only serves the purpose of covering the stresses resulting from the nozzle loads. Reinforcements in the nozzle must not be used to make the margin of safety available.The margin of safety is only required for process nozzles of all nominal diameters. It does not have to be adopted for manholes,
28、handholes and instrument nozzles.If the opening has been dimensioned as specified above, the general analysis of the nozzle loads by means of a WRCB calculation by the manufacturer can be omitted.The following is a table showing the necessary margins of safety against the wall thickness according to
29、 the above formulas.Project No.:Project Code:Linde Document No:Issue: 01Page 4 of 14Wallthickness=100 mm5,59% 5,49% 5,39% 5,30% 5,21%5,12% 5,03% 4,95% 4,87% 4,79% 4,71% 4,64% 4,57% 4,50% 4,44% 4,37% 4,31% 4,25% 4,19% 4,13% 4,07% 4,02% 3,97% 3,91% 3,86% 3,81% 3,77% 3,72% 3,67% 3,63% 3,59% 3,54% 3,50%
30、 3,46% 3,42% 3,38% 3,35% 3,31% 3,27% 3,24% 3,20% 3,17% 3,14% 3,10% 3,07% 3,04% 3,00%3,00%Project No.:Project Code:Linde Document No:Page 5 of 14Issue: 01Proceeding according to AD-B9The regulations concerning the calculation of openings in cylindrical, conical and spherical shells are to be found in
31、 AD 2000-Merkblatt B9. The design for openings with and without reinforcing pads has to be performed according to chapter 4.1:p)人(K py A (Ki p 人、p 人 /八 AcrO + +* A.(t2 2 * Ap (1 )20 J I S20 J5 20 J 10The respective areas for the calculation of the opening can be seen in the following picture:ss-q-c2
32、H Hd*In the first step, using the minimum required wall thickness and the nozzle wall thickness as well as a possible reinforcing pad, the opening is dimensioned in such a way as to exactly satisfy equation ，ieK2Is 20JV S20 JIn the next step the required margin of safety R for the corroded shell wal
33、l thickness T (including a possible reinforcing pad thickness) is determined according to the table. Subsequently, the shell wall thickness or the reinforcing pad thickness respectively (but not the nozzle thickness) have to be increased respectively in order to obtain the margin of safety in the op
34、ening under consideration. The existence of the required margin of safety has to be verified with the increased wall thickness as follows:20；- AT +(KIS20； Abi +Ki20 Jnewa new 1 + -. (3)100Only the terms containing the shell thickness and the reinforcing pad thickness, namely Aa2 and Ap change at all
35、. This fact becomes clear when looking at equation (3) - the upper index for 禽，Aand(has been changed to newAs a last step it is necessary to perform an as built calculation and to show the actual available margin of safety.Project No.:Project Code:Linde Document No:Issue: 01Page 6 of 14In case of a geometry with a reinforcing pad the requirements according to AD-B9, chapter 4.3 have to be observed. Equation (6) in AD-B9 shows the calculation of the effective nozzle length.In addition, the following conditions have to be reg