An Optimum Design of Pressure Vessel by using PV-ELITE Software

Abstract

The safety factor of a pressure vessel is related to both the tensile stress and yield strength for material allowance. ASME code section VIII has fully covered these two on the construction code for pressure vessel. This code section addressed mandatory and non-mandatory appendixes requirement, specific prohibition, vessel materials, design, fabrication, examination, inspection, testing, certification, and pressure relief. Mechanical design of a horizontal pressure vessel based on this standard had been done incorporating PV ELITE software. Analyses were carried out on head, shell, nozzle and saddle. The input parameters are type of material, pressure, temperature, diameter, and corrosion allowance. Analysis performed the calculations of internal and external pressure, weight of the element, allowable stresses, vessel longitudinal stress check, nozzle check and saddle check.

Introduction

I. INTRODUCTION

Pressure vessels are leak proof containers, as the name implies, their main purpose is to contain a given medium under pressure and temperature. Pressure vessels are commonly used in industry to carry both liquid and gases under required pressure and temperature limit. This pressure and temperature comes from an external source or by the application of heat from a direct or indirect source or any combination of them. They may be of any shape and size ranging beer canes, automobile tires or gas storage tank, to more sophisticated ones encountered in engineering applications. Pressure vessels; commonly have the cylindrical, spherical, ellipsoidal, conical or a combination of these shapes. However, some pressure vessels are named after the type of function they required to perform. For example, the distillation column is a vessel used in oil and petroleum refining process. The heat exchanger used in many types of industries to transfer heat from one fluid to another fluid, acted as same. Also, reactor is a vessel, which is used for chemical reaction of contained substance. The material comprising the vessel is subjected to pressure loading and hence stresses from all direction. The normal stresses resulting from this pressure are functions of diameter of the elements under consideration, the shape of the pressure vessel as well as the applied pressure.

II. DESIGN CODES

Pressure vessels are always works under certain pressure and temperature along with contain sometime lethal substances which are hazardous for both human and environment. Considering this, safety implications and hazards arising from the operation of pressure vessels, there is an obvious need to standardize engineering and fabrication practices. To assure minimum safety standards, several design codes have prepared and developed. In Europe most widely National codes are:

GERMANY - AD MARKBLATTER, BRITISH – BS1500, BS 1515, ITLAY – CCPA

In the United States and Canada, the most widely used Standards are the ASME boiler and pressure vessel code, published by American Society of Mechanical Engineers (ASME). ASME section VIII deals with the design for pressure vessels, materials specification, fabrication, opening and reinforcement, testing and marking, inspection and other mandatory or non mandatory appendixes. Section VIII contains three divisions, covering the different pressure ranges:

Division 1: up to 3000 psi (200 bar)

Division 2: up to 10000 psi (690 bar)

Division 3: above 10000 psi (above 690 bar )

ASME section VIII, Division 1, deals with conventional pressure vessels means design by rule, while division 2, deals with stringent alternative rules means design by analysis, and division 3 deals with design of Nuclear Equipment.

Vessels failure can be grouped into four major categories, which describe why a vessel failure occurs. Failures also grouped into types of failures, which describe how the failure occurs mean each failure contains its failure history, why and how it occurs. There are many reasons of vessels failure such as: Improper material selection, defected material. Incorrect design data, incorrect or inaccurate design method or process, inadequate shop testing. Improper fabrication process, poor quality control, insufficient fabrication process including welding, heat treatment and forming methods.

In order to meet a safe design, a designer must be familiar with the above mentioned failure and its causes. There have a few main factors to design safe pressure vessel. This study is focusing on analyzing the safety parameters for allowable working pressure. Allowable working pressures are calculated by using PV ELITE software which compile with the ASME section VIII, rules for construction pressure vessels. The objectives of the study is to design pressure vessel according to input data and analyze the safety parameters of each component for its allowable working pressure using; PV ELITE software.

IV. DISCUSSION

Design of pressure vessel can be finished quickly by applying numerous calculations in software. The drawing process was simpler associated to the software. This study only investigated a part of parameters design. There are other parameters that are not considered such as thermal loads, wind loads, seismic load, transportation load, erection load and fabrication methods etc. however this insufficiency can be overcome by mastering software.

V. ACKNOWLEDGMENT

The author would like to thank following guises for his constant encouragement and able guidance. Prof.R.R.Kulkarni Prof.Kedar Bhagwat Siddhant Collage of Engineering, Sudumbare , Pune-412109

Conclusion

Mechanical design of pressure vessel had been done using graphical based software. Drawing process was very easy and input can be entered in the same screen. The result fully complied with standard code and had been employed on practical design of pressure vessel. Research can be explored to into account other parameters. Selection material referring to ASME, standard can also been developed. The behavior of pressure vessels in case of fluctuating load could be a challenging matter for future research

References

[1] ASME section VIII division 1, 2007. [2] Moss D.R.Pressure Vessel design manual Third edition.

Copyright

Copyright © 2023 Chetan Patil. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.