Skip to main content
Top

2021 | Book

New Theory and Design of Ellipsoidal Heads for Pressure Vessels

Authors: Prof. Jinyang Zheng, Dr. Keming Li

Publisher: Springer Singapore

insite
SEARCH

About this book

This book is the first monograph focusing on ellipsoidal heads, which are commonly used as an end closure of pressure vessels in chemical, petroleum, nuclear, marine, aerospace and food processing industries. It provides a comprehensive coverage of stress, failure, design and fabrication of ellipsoidal heads. This book investigates in detail buckling/plastic collapse behaviors of ellipsoidal heads using nonlinear finite element methods and experiments. Buckling/plastic collapse experiments are performed on 37 ellipsoidal heads which cover various geometric parameters, material and fabrication methods. In particular, modern measurement technologies, such as 3D laser scanning, are used in the experiments of these ellipsoidal heads including large heads with a diameter up to 5 metres. Moreover, this book presents new formulas for accurate prediction of buckling/plastic collapse pressures of ellipsoidal heads. Using elastic-plastic theory, this book proposes a new failure mechanism-based method for design of ellipsoidal heads. Compared to other methods in current codes and standards based on elastic or perfectly plastic theory, the new design method can fully develop the head’s load-carrying capacity, which reduces head thickness and thus cost. Also, this book studies control on fabrication quality of ellipsoidal heads, including shape deviation, forming strain and forming temperature. It is useful as a technical reference for researchers and engineers in the fields of engineering mechanics, engineering design, manufacturing engineering and industrial engineering.

Table of Contents

Frontmatter
Chapter 1. Introduction
Abstract
This chapter addresses the various types of heads including flat, conical, shallow spherical, hemispherical, torispherical and ellipsoidal. The ellipsoidal head is the ideal head choice for pressure vessels due to its good stress distribution and ease of fabrication. The most widely used steels and their properties are described. Stress analysis of ellipsoidal heads under internal pressure is performed using elastic or elastic-plastic theory, and compared with those of torispherical heads. This chapter reviews the progress of research on the failure modes (i.e., buckling and plastic collapse), as well as formulas for predicting the buckling pressure and plastic collapse pressure of ellipsoidal heads respectively. It provides a detailed review of the design methods of ellipsoidal heads in the pressure vessel codes and standards including ASME VIII-1 and VIII-2, GB/T 150.3, JB 4732 and EN 13445-3. It also reviews fabrication methods including pressing, spinning and assembly from formed segments, as well as fabrication requirements including shape deviation and forming strain. Finally, it presents the design methods of special ellipsoidal heads including heads under external pressure, heads with variable thicknesses, and heads with nozzles.
Jinyang Zheng, Keming Li
Chapter 2. Buckling of Ellipsoidal Heads
Abstract
This chapter presents an in-depth investigation into the buckling of ellipsoidal heads under internal pressure. Key technologies for buckling experiments of large heads with a diameter up to 5 m are presented, including design of reusable test vessels, measurement of initial shape and deformation with 3D laser scanning, and measurement of large strains under hydraulic pressure. Models for buckling simulation of ellipsoidal heads are generated using the nonlinear finite element method, and perfect and actual shapes are both considered. Buckling behavior of ellipsoidal heads is presented in detail, and buckling characteristics are obtained. Moreover, the effects of material properties, geometric parameters and shape imperfection on the buckling of ellipsoidal heads are investigated. A new buckling criterion is developed in order to determine whether ellipsoidal heads will buckle or not. A new formula for predicting buckling pressure is also proposed for ellipsoidal heads at which buckling occurs. The predictions of the new formula are compared with experimental results as well as other formulas.
Jinyang Zheng, Keming Li
Chapter 3. Plastic Collapse of Ellipsoidal Heads
Abstract
This chapter presents an in-depth investigation of the plastic collapse of ellipsoidal heads under internal pressure. Plastic collapse experiments are performed on 31 ellipsoidal heads covering various geometric parameters, steel and manufacturing methods. Finite element models for calculating the plastic collapse pressure of ellipsoidal heads are developed, taking into account the effects of material strain hardening and geometric nonlinearity. The effects of geometrical and material parameters on plastic collapse pressure are investigated. A new simple formula for predicting the plastic collapse pressure of ellipsoidal heads is developed. The predictions of the new simple formula are compared with experimental results as well as other predictions.
Jinyang Zheng, Keming Li
Chapter 4. New Method for Design of Ellipsoidal Heads
Abstract
First, the problems of the design methods for ellipsoidal heads under internal pressure in the current codes and standards are discussed, including local buckling criteria, geometric equivalence as torispherical heads and strengthening effect of nonlinearity on strength. Second, a new failure mechanism-based design method for ellipsoidal heads is developed. New design formulas for calculating the minimum required thicknesses to prevent the buckling and plastic collapse of ellipsoidal heads are proposed respectively. Moreover, the new local buckling criterion is used to determine whether buckling is considered or not. Finally, the new method for the design of ellipsoidal heads is compared with those in the current codes and standards.
Jinyang Zheng, Keming Li
Chapter 5. Control of Fabrication Quality of Ellipsoidal Heads
Abstract
The effects of fabrication (shape deviation, forming strain and forming temperature) on ellipsoidal head performance (load-carrying capacity and mechanical properties) are investigated. Methods for controlling the fabrication quality of ellipsoidal heads are developed, including a method for evaluating the shape deviation based on non-contact measurement, a formula for predicting the maximum forming strain, and a method for determining the warm forming temperature to avoid strain-induced martensitic transformation.
Jinyang Zheng, Keming Li
Chapter 6. Summary
Abstract
This book is intended to provide comprehensive coverage of the stress, failure, design and fabrication of ellipsoidal heads for pressure vessels, which are summarized in this chapter.
Jinyang Zheng, Keming Li
Metadata
Title
New Theory and Design of Ellipsoidal Heads for Pressure Vessels
Authors
Prof. Jinyang Zheng
Dr. Keming Li
Copyright Year
2021
Publisher
Springer Singapore
Electronic ISBN
978-981-16-0467-6
Print ISBN
978-981-16-0466-9
DOI
https://doi.org/10.1007/978-981-16-0467-6

Premium Partners