IJSRD - International Journal for Scientific Research Research & Development| Vol. 4, Issue Issue 05, 2016 | ISSN (online): 2321-0613
Design & Analysis of Vertical Pressure Vessel by using ASME Codes V. P. Gawade 1 Prof. M. U. Gaikwad 2 1 P.G. Student 2Professor 1,2 Department of Mechanical Engineering 1,2 Dattakala Group of Institutions Faculty of Engineering Swami Chincholi, Savitribai Phule Pune University, Maharashtra — The pressure vessel is designed for internal Abstract pressure using ASME Codes. The components of the pressure vessel are designed by calculating the factors like thickness of the shell, head, stress analysis etc. To validate the design result the pressure vessel is modeled and analyzed analyzed in ANSYS. The preferred method to conduct the analysis is FEA. Key words: ASME, FEA, Pressure Vessel Design, Ellipsoidal, Analysis I. I NTRODUCTION NTRODUCTION Pressure Vessels are the reservoir of fluids at pressure more or less than ambient, internal or external pressure. The pressure source can be pump, compressor, fluid head etc. Pressure vessels used in industrial applications such as in thermal and nuclear power plants, petrochemical refineries, process and chemical industry etc. The shapes of pressure vessels are mainly spherical or cylindrical with dished ends. Designing is to calculate the dimensions of a component so that it can endure the applied loads and function. It also involves the process of estimating the stresses for the specified loads at different points of a component [1]. While designing the pressure vessel safety is the important concern because the rupture of pressure vessel or explosion may cause loss property& lives. Further the analysis (finite element) which is a subpart of the design process includes the estimation of stresses and failure of the pressure vessel and its components. This research paper highlights the importance of ASME Code in designing of pressure vessel by validating the design using FEA. Classification of pressure vessels are: The pressure vessels are classified as per below A. According to thickness
1) 2)
Thin walled cylinder – cylinder – when when t/d < 0.1 Thick walled cylinder- when t/d > 0.1
B. According to Position
1) 2) 3)
Horizontal pressure vessel Vertical pressure vessel Inclined pressure vessel
C. According to end construction
1) 2)
Closed end Open end II. LITERATURE REVIEW
Apurva R. Pendbhaje, Mahesh Gaikwade, Nitin Deshmukh & Rajkumar Patil[5] present design and analysis of pressure vessel using ASME codes & standards to legalize the design. Pressure rise is developed in the pressure vessel. The aim of this design is the safety of pressure vessel due to the impact of potential. This avoids the possible accidents.
There have a few factors which are used to design the safe pressure vessel. These factors used for analyzing the safety parameter for allowable working pressure. These pressures are calculated by using Pressure Vessel Design Manual by Dennis Moss, third edition. Mayank Nirbhay, OrashantTripathi & Vivek Kumar Gupta [3] present the design of a pressure vessel is carried out using ASME Codes. In this paper designed the various components of the pressure vessel by calculating the necessary design factors like thickness of the shell, head, stress analysis etc. To validate the design result the pressure vessel is modeled and analyzed in ABAQUS. This proposed method is to conduct the analysis is finite element method. Further the study in the variation of effective parameters in design of pressure vessel is done. To study the variation different graphs are plotted. internal pressure and diameter of shell. The applicability of various types of heads is also evaluated. Shyam R. Gupta, &Chetan P. Vora[14] present some of the developments in the determination of factors in stress concentration in pressure vessels at openings, stress analysis of different types of end connections and minimization stress with the help of optimize location and angle of nozzle on shell and head. Pressure vessels are designed by the ASME pressure vessel code. The code gives for thickness and stress of basic components; from these values the designer can select appropriate analytical procedure for determining stress due to other loadings. Shaik Abdul Lathuef & K. Chandra Sekhar [7] discusses some of the potential unintended consequences related to Governing Thickness of shell as per ASME. Here have scope to change the code values by take the minimum governing thickness of pressure vessel shell to requirements and also relocate of nozzle location to minimize the stresses in the shell. The value of the factor of safety results in economy of material this will lead to thinner and more flexible and economical vessels. The stress is evaluated in the vessel by Zick analysis approach. III. THEORETICAL BASIS A. Design Method / Procedure
The pressure vessels is designed using ASME Section VIII Division-I. The analytical method is followed for determining thickness and stress of components of pressure vessel. Here the component of pressure vessel refers to shell, head and nozzles, skirt support. There are various factors [3] which must be considered while selection and designing of the pressure vessel such as Dimensions and geometry thickness diameter, length, and their limitations. Operating conditions Functions and location, corrosive nature, Nature of
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Design & Analysis of Vertical Pressure Pressure Vessel by using using ASME Codes (IJSRD/Vol. 4/Issue 05/2016/04 05/2016/042) 2)
fluid, Materials, its physical properties and cost. Type of failure Fabrication techniques Theories and type of failure Economic consideration
B. Design of Components of Pressure Pressure Vessel
Generally a pressure vessel consists of a shell with closed ends. Plates are used to manufacture the pressure vessel components. Parts or components are attached either by welds joints. Thus a joint efficiency factor is considered into account. Design procedure as in ASME Code Section VIII Div-I [11] is followed to design a long vertical pressure vessel with Ellipsoidal heads. The step involved in designing the vessel is shown in the flowchart shown show n in “Figure“Figure -1”
3) Calculation of the shell thickness under internal pressure for vertical vertical vessel- As per UG-27 a) Circumferential Stress When thickness does not exceed one half of the inside radius of vessel or P does not exceed 0.385SE, the following formulas used:() = / (SE-0.6P) – (3.1) Where, Ri= R + C.A. = 600+1.5 = 601.5mm or 60.15cm tr= 28*60.15/(1284.84*1-0.6*28)= 13.28 mm Total shell thickness = tr + C.A. = 13.28+1.5= 14.78mm b) Longitudinal Stress When the thickness not to exceed one half of the inside radius or P does not exceed 1.25SE, the following formulas to be used:() = / (2SE-0.4P) - (3.2) Where, Ri= R + C.A. = 60 0+1.5 = 601.5mm or 60.15cm tr= 28*60.15/(2*1284.84*1-0.4*28)= 6.58 mm Total shell thickness = tr + C.A. = 6.58+1.5= 8.08mm Therefore, Maximum thickness considered is 13.28 mm. Generally the next standard fabrication plate available is15 mm thick, so the shell thickness under internal pressure is 15 mm. 4) Design of head-as per UG 31 Ellipsoidal Heads withts/L≥ withts/L≥0.002. The required thickness of a dished head of ellipsoidal, in which half the minor equals one-fourth of the inside diameter of skirt determined by - (3.3) = D / (2SE-0.2P) Where, D= ID + (C.A.*2) = 1200+3 = 1203mm or 120.3 cm tr= 28*120.3/(2*1284.84*1-0.2*28)= 13.13 mm Total shell thickness=tr+C. A. = 13.13+1.5=14.63 mm As per design inputs this vessel will never undergo vacuum condition either partially or fully in its service life. Hence design for external pressure is not carried out.
IV. FINITE ELEMENT ANALYSIS OF PRESSURE VESSEL Fig. 1: Design procedure flowchart 1) Selection of material of elements The selection of material of pressure vessel as per ASME section II part A [12] is SA516 Grade 60 Carbon steel. Properties of material (SA516 Grade 60) for the shell and heads are shown in Table-1: Maximum allowable stress 1284.84kgf/cm2 value (S) (126N/mm2) Density 7850 kg/m3 Table 1: Properties of Material 2) Design data Input Code for design ASME Sec-VIII Div-I Internal design pressure (P) 28 Kg/cm2 External design pressure Nil Design temperature ( oC) 200oC Nominal inside diameter (Di) 1200 mm Corrosion allowance (C.A.) 1.5 mm Weld joint efficiency (E) 1 Shell length (L) 23950 mm Type of head Ellipsoidal Material of construction SA 516 Gr. 60 Table 2: Design Specifications
Objective of the analysis is to conduct FEA of a long vertical pressure vessel to determine the maximum stress induced for a safe design, the maximum induced stress is less than the maximum allowable stress. A. Modeling and Analysis Software
The detailed 3Dmodeling done in Solid works 2016 and analysis of pressure vessel was done in ANSYS. It is a general purpose Modeling and Analysis package for numerically solving a variety of mechanical engineering problem. 1) Modeling Since the main aim of the investigation is to determine the maximum induced stress. During modeling many small features of the vessel were not modeled because they will have only a local effect and will not play much significant role. Shell and head of the vessel were formed as shell by revolve tool in the Solid works 2016 part module as shown in Figure-2. The part modeling is done on the basis of the dimensions which are calculated in designing procedure.
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Design & Analysis of Vertical Pressure Pressure Vessel by using using ASME Codes (IJSRD/Vol. 4/Issue 05/2016/04 05/2016/042) 2)
Fig. 5: Stress distributions in the pressure vessel. Fig. 2: Modeling the pressure vessel in Solid Works 2016. 2) Boundary and Loading Conditions: The pressure vessel is fixed at bottom flange of skirt support.& inside pressure vessel is set to 28 kg/cm 2 pressure as shown in figure-3.
Fig. 6: Stress distributions in t he Ellipsoidal bottom head of the pressure vessel.
Fig. 3: Fixed support at bottom skirt of column B. Meshing
Cylindrical bodies are swappable & hence hex elements are preferred for messing. For other body parts tetrahedron elements are used. Sizing of 30 mm to150 mm. Instead of using a coarse mesh, fine mesh is used to produce accurate results, as shown in Figure-4.
Fig. 7: Stress distributions in the Ellipsoidal top head of the pressure vessel. VI. CONCLUSION
Fig. 4: Fine meshing of the pressure vessel with Element size 30mm of 150mm. V. A NALYSIS RESULTS RESULTS The tress distribution is as shown in Figure-5, 6&7 the maximum stress induced in the vessel is 117.75 N/mm 2 (or 1200.7 kg/cm2) which is less than the maximum allowable stress i.e. 125.99 N/mm2(or 1284.84 kg/cm2), shown in Table-1. Thus, Analysis results achieved concludes that the design is appropriate and safe.
Pressure vessel is designed using ASME Code Sec. VIII Div-I and analysis to be done in ANSYS. The analysis results are so close to the analytical design, hence both the data validates. The result obtained is that the induced stress is less than the maximum allowable stress. The analysis result proved that the design procedure adopted is appropriate. The FEA also helps to study the actual stress distributions in pressure vessel components. R EFERENCES EFERENCES [1] SandipGond, Akhilesh, Anoop Singh and Vinodsharma “Design & Analysis of the pressure vessel”, International Journal of Scientific & Engineering Research, Vol.5 issue 4 April 2014. [2] DigvijayKolekar and Jewargi S. S. “Stress Analysis of Pressure Vessel with Different Types of End Connections –A Review”, International Journal of
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Science, Engineering and Technology Research, Vol.3 issue 12 December 2014. [3] MayankNirbhay, OrashantTripathi&Vivek Kumar Gupta “Implementation of ASME Codes to Design A Pressure Vessel&Toexplore the Influence of Various Design Parameters”, International Journal of Engineering Research &Technology,Vol.3 Issue IJanuary 2014. [4] Aniket A. Kulkarni&Keshav H. Jatkar“A Review onOptimization of Finite Element Modeling for Structural Analysis of Pressure Vessel”, International Journal of Engineering Trends and Technology, Vol.12 Number 1-June 2014. [5] Apurva R. Pendbhaje, Mahesh Gaikwade, NitinDeshmukh&RajkumarPatil“Design & Analysis of Pressure Vessel”, International Journal of Innovative Research in Technology & Science, Vol.2 Number 3. [6] Mahesh B. Gosavi, Prof. A. S. Rao&VinnayPatil“A Reviewon Failure Modes of Composite Pressure Vessel”, InternationalJournal of Engineering Development And Research, Vol.2 Issue-1ISSN: 23219939. [7] Shaik Abdul Lathuef& K. Chandra Sekhar“Design & Structural Analysis of Pressure Vessel Due to Change of Nozzle Nozzle Location & Shell Thicknesses”, International Journal of Advance Engineering Research and Studies, Vol. I Issue-IIJanuary - March, 2012/218-221. [8] Prof. Nitinchandra R. Patel, AvinahVasava, AlpeshKunapara&Savan Patel “Design & Analysis of Pressure VesselAmalgamating with selection of material used in marineApplication”, International Journal of Innovative Research in Science, Engineering and Technology Vol. 2, Issue 6 June 2013. [9] Usman Tariq Murtaza& Mohammad JavedHyder “Design by Analysis ver sus sus Design by Formula of a PWR Reactor Pressure Vessel”, Proceedings of the International Multi conference of Engineers and computer scientists 2015 Vol. II, IMECS 2015, March 18-20, 2015, Hong Kong. [10] A. Di Carluccio, G. Fabbrocino, E. Salzano& G. Manfredi“Analysis of pressurized horizontal vessel under seismicExcitation”, The 14th World Conference on Earthquake Engineering October 12-17, 2008, Beijing, China. [11] “Rules for construction of pressure vessels”Section VIII,Division-I, ASME Boiler andPressure Vessel Code, 2015Edition. [12] “Ferrous material specification” Section II Part -A, ASMEBoiler and Pressure VesselCode, 2015edition. [13] Pressure vessel Handbook, 10th ed., Eugene F. Megyesy, Publishing Inc. PO Box 35365. [14] Shyam R. Gupta,&Chetan P. Vora“A Review P aper on Pressure Vessel Design andAnalysis”,International Journal of Engineering Research & Technology (IJERT)Vol. 3 Issue 3, March – March – 2011 2011
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