Design Assessment and Parametric Study of Expansion Bellow
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1. This document presents the design, parametric study, and analysis of an expansion bellow. The author developed a U-shaped expansion bellow design using ASME and EJMA design codes and conducted a finite element analysis. 2. A parametric study was carried out to analyze how changes in design parameters like diameter, pitch, length, pressure, and temperature affect the total stress on the bellow. The study found that total stress initially increases then decreases with changes to these parameters. 3. The stress components and cycle life were calculated and compared between the ASME and EJMA designs. The EJMA design produced lower stresses and higher cycle life compared to the ASME design.
![International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 04 Issue: 12 | Dec-2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 315
CONCLUSION
[1] The total stress estimated from the design based on
EJMA depends on the meridional membrane stresses
and meridional bending stress due to the pressure and
the total equivalent displacements in axial direction
without considering the others effects like temperature
etc. While in the design with ASME section VIII also
considers the effects of operating temperature of
bellows using the modules of elasticity both at room
temperature and operating temperatures.
[2] Fatigue strength factorisneglectedwhiledesigningwith
the EJMA design code but the considered while
designing with the design code-ASME section VIII with
its effecting factors like thickness changes, various
surface factors and weld geometrics.
REFERENCES
[3] Sungchul Kim and Bongchoon Jang “Development of
Bellows Design SoftwareusingMATLAB”,IndianJournal
of Science and Technology, Vol 8(S8), 201–206, April
2015
[4] Gaurav R. Mohite, A. P. Edlabadkar, “Analysis of
expansion joint in heat exchanger using finite element
analysis method”, IJPRET, 2014; Volume 2 (9):436-449,
Published Date: 01/05/2014
[5] Brijesh M. Patel, B.D. Patel, V.M. Prajapati, “A Critical
Review on Metal Expansion Bellows”, International
Journal of Engineering Science and Innovative
Technology (IJESIT) Volume 2, Issue 2, March 2013
[6] Jayesh .B Khunt, Rakesh .P Prajapati, “Design And
Thermal Analysis Of Thermal Expansion Joint In
Industrial Application” IJIRST | Volume 1 | Issue 6 |
November 2014
[7] Brijesh kumar. M. Patel, V.A. Patel, ”Design,
Manufacturing and Analysis of Metal Expansion
Bellows” IJESIT Volume 2, Issue 3, May 2013
[8] EJMA (Expansion Joint Manufacturing Association)
Ninth Edition.
[9] ASME Section VIII Division-1 Appendix26,2010.(2004)
1–6.](https://image.slidesharecdn.com/irjet-v4i1257-180111072059/85/Design-Assessment-and-Parametric-Study-of-Expansion-Bellow-4-320.jpg)
Design Assessment and Parametric Study of Expansion Bellow
- 1. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 04 Issue: 12 | Dec-2017 www.irjet.net p-ISSN: 2395-0072 © 2017, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 312 Design Assessment and Parametric Study of Expansion Bellow Tuhin Halder1, Ankush K. Biradar2, Dr. S. Ram Reddy3 1ME Student, Mechanical Engineering Department, BRHCET 2Head of the Department, Mechanical Engineering Department, BRHCET 3Dr. S. Ram Reddy, Mechanical Engineering Department ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - Design of Expansion bellow is a very critical activity in the process of designofanExpansionJoints.Major difficulties arrive in research process because thereareonly few numbers of literatures, books and research papers are available to guide the researchers to develop new design with its complex shapes. For the purpose of safeanddurable operation throughout the estimated working life it is necessary to consider various factors whiledesign.Toarrive at successful design of expansion bellow it is requires to change the numbers of design parameters and do a lots numbers of iterative calculation for a long time. In this current research paper author developed the design of U shaped expansion bellowwiththe help of Expansion design codes like ASME and EJMA.A detail parametric study is carriedoutbaseduponthedesignoutput and verified through FEA process. Key Words: Expansion bellow, EJMA,ASME,FEA 1. METHODOLOGY 1. This project methodology starts with the study of various literature s and journals related to the bellow and expansion joints. 2. Then select various design parameters as per the suitable conditions like applications, durations of applications, space available etc. 3. Then Design the bellow with thechosenparameters with various design codes and standards. 4. Then analyse the various design results to find the optimum one. 5. Then do the parametric study to ensure theimpacts of the parameters on the stress values,lifeofbellow etc. 6. Finally conclude the entire process. 2. BELLOW DESIGN PARAMETERS To design a simple Expansion bellow for certain Design Pressure with requisite certain minimum nos cycle of operation the designer need to consider certaininputdesign parameters and material properties as mentions below A. Essential Material properties for Bellow design. PARAMETERS NOTATIONS Modulus of elasticity at Room Temp for Bellows Eb(RT)/Eo Modulus of elasticity at Working Temp for Bellows Eb(dt) Modulus of elasticity for ring at design temp Er(DT) Modulus of elasticity for collar at design temp Ec(DT) Modulus of elasticity at Working Temp for collar Ebc /Eb(DT) Modulus of elasticity (overall) Eb Yield strength at design temperature of the actual Bellows material after completion of Bellows forming and any applicable heat treatment Sy B. Design input parameters PARAMETERS NOTATIONS Pipe outer dia OD Bellow ID Db Bellows Thickness t Number Of Plys n
- 2. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 04 Issue: 12 | Dec-2017 www.irjet.net p-ISSN: 2395-0072 © 2017, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 313 Mean radius of bellows convolution rm Pitch of Convolution q Number of Convolutions No Tangent Length Lt Bellows tangent collar thickness tc Collar Length Lc Length of the bellow convolution Lb Design Pressure P Design Temperature T Axial Compression Xc Axial Extention Xe Lateral Movement y Angular Movement θ Depending upon the above mentioned material properties and input parameter others auxiliaryparameterscanbefind out from EJMA and ASME Codes . 3. STRESS CLACULATIONS AS PER EJMA: 1. Tangent Circumferential Membrane Stress Due to pressure ( S1 ) S1= P*(Db + n*t)^2 * Lt*Eb*K / (2 * (n*t*Eb*Lt(Db+ n*t)) + (tc*K*Ec*Lc*Dc)) 2. Bellows Circumferential Membrane Stress Due to pressure ( S2 ) S2 = (P*Dm*Kr*q)/(2*Ac) 3. Bellows Meridional Membrane stress Due to pressure ( S3 ) S3 = P*W / (2 * n * tp) 4. Bellows Meridional Bending Stress Due to pressure ( S4 ) S4 = (P / 2n) * (W / tp)^2 * Cp EVALUATION S1 & S2 <Cwb * Sab S3+S4 < Cm * Sab All the conditions should be satisfied 5. Bellows Meridional Membrane Stress due to deflection ( S5 ) S5 = Ebr * (tp)^2 * e / (2 * W^3 * Cf) 6. Bellows Meridional bendingStressduetodeflection ( S6 ) S6 = 5 * Ebr * tp * e / (3 * w^2 * Cd) 7. Total Stress ( St ) = 0.7*(S3+S4)+S5+S6 8. Cycle Life ( Nc ) = (C/(St-b))^a Where Where a=3.4,b =54000,c=1860000 4. STRESS CLACULATIONS AS PER ASME: 1. Tangent Circumferential Membrane Stress (S1) S1=(P*(Db+(n*t))^2*Lt*Eb*k)/(2*(n*t*Eb*Lt*(Db (n*t))+(tc*k*Ebc*Lc*Dc))) 2. The circumferential membrane stress due to pressure S2= (P*Dm *q)/(2*A) for intermediate convolution S2=(q*Dm+Lt(Db+nt))*P/2(A+n*tp+tc*Lc) for end convolution 3. The meridional membrane stress due to pressure (S3) S3= P*w / (2 * n * tp) 4. The meridional bending stress due to pressure S4= (P*Cp/(2*n))*(w/tp)^2 EVALUATION S3 + S4 ≤ Kf*S Kf = 3.0 for formed bellows Kf=1.5 for annealed bellows 5. Meridional membrane stress (S5) S5= Ebr * (tp)^2 * dq / (2 * w^3 * Cf) 6. Meridional bending stress (S6) S6= 5 * Ebr * tp * dq / (3 * w^2 * Cd) 7. Total Stress ( St ) = 0.7*(S3+S4)+S5+S6 8. Cycle Life ( Nc ) =( k0/kg*(E0/Eb)St-S0))^2 Where kg*(E0/Eb)St ≥ 65,000 psi St is expressed in psi, Ko=5.2 _ 106 and So=38,300
- 3. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 04 Issue: 12 | Dec-2017 www.irjet.net p-ISSN: 2395-0072 © 2017, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 314 4. DESIGN RESULTS 5. DESIGN ANALYSIS: From the above design it is observed that though the input parameters are same for the both codal design method (ASME and EJMA), the output stress components are different because of their respective design philosophy. The nature of stress components distributionareshownthrough the graph bellow. FIGURE: VIEW OF VARIOUS STRESS COMPONENTS The above design can be analysed in that forthesamedesign parameters 1. The value of a) Tangent Circumferential Membrane Stress (S1) b) Bellows Meridional Membrane stress (S3) c) Bellows Meridional Bending Stress (S4) Are same for both ASME and EJMA code basis Design 2. The value of d) Bellows Circumferential Membrane Stress (S2) is higher in EJMA with respect to ASME code basis Design 3. The value of e) Bellows Meridional Membrane Stress due to deflection (S5) f) Bellows Meridional bending Stress due to deflection (S6) g) Total stress (St) Are lower in EJMA with respect to ASME code basis Design 4. The cycle life of bellow is higher in EJMA with respect to ASME code basis Design 7. PARAMETRIC ANALYSIS: In the above design process the impacts of changesofdesign parameters on total stress in both the design process mentioned below – With the initial rise in bellow convolution diameter, pitch, length, pressure & temp. increase the total stress increases as shown in below graph . FIGURE : NATURE OF CHANGE IN TOTAL STRESS WRT DIAMETER, PITCH, LENGTH, PRESSURE & TEMP With the increase of the depth of convolution the total stress vale decrease in both the design process as shown bellow FIGURE : NATURE OF CHANGE IN TOTAL STRESS WRT BELLOW CONVOLUTION DEPTH With the increase of the thickness of the bellow the total stress increase with higher rate as shown inthegraph below FIGURE : NATURE OF CHANGE IN TOTAL STRESS WRT BELLOW STRESS EJMA ASME UNITS S1 3964.019 3964.019 Pa S2 7312.319 5752.273 Pa S3 1069.718 1069.718 Pa S4 33597.47 33597.47 Pa S5 1738.486 2210.82 Pa S6 237959.2 343993.3 Pa St 263964.8 370471.2 Pa NC 1663.59 412.2956 Nos.
- 4. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 04 Issue: 12 | Dec-2017 www.irjet.net p-ISSN: 2395-0072 © 2017, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 315 CONCLUSION [1] The total stress estimated from the design based on EJMA depends on the meridional membrane stresses and meridional bending stress due to the pressure and the total equivalent displacements in axial direction without considering the others effects like temperature etc. While in the design with ASME section VIII also considers the effects of operating temperature of bellows using the modules of elasticity both at room temperature and operating temperatures. [2] Fatigue strength factorisneglectedwhiledesigningwith the EJMA design code but the considered while designing with the design code-ASME section VIII with its effecting factors like thickness changes, various surface factors and weld geometrics. REFERENCES [3] Sungchul Kim and Bongchoon Jang “Development of Bellows Design SoftwareusingMATLAB”,IndianJournal of Science and Technology, Vol 8(S8), 201–206, April 2015 [4] Gaurav R. Mohite, A. P. Edlabadkar, “Analysis of expansion joint in heat exchanger using finite element analysis method”, IJPRET, 2014; Volume 2 (9):436-449, Published Date: 01/05/2014 [5] Brijesh M. Patel, B.D. Patel, V.M. Prajapati, “A Critical Review on Metal Expansion Bellows”, International Journal of Engineering Science and Innovative Technology (IJESIT) Volume 2, Issue 2, March 2013 [6] Jayesh .B Khunt, Rakesh .P Prajapati, “Design And Thermal Analysis Of Thermal Expansion Joint In Industrial Application” IJIRST | Volume 1 | Issue 6 | November 2014 [7] Brijesh kumar. M. Patel, V.A. Patel, ”Design, Manufacturing and Analysis of Metal Expansion Bellows” IJESIT Volume 2, Issue 3, May 2013 [8] EJMA (Expansion Joint Manufacturing Association) Ninth Edition. [9] ASME Section VIII Division-1 Appendix26,2010.(2004) 1–6.