Casing Design – Session 1

This course focuses on casing design, both from an engineering and an operational perspective. Design concepts are provided for a wide range of straightforward and hostile environments. It examines the nomenclature of casing design, manufacturing processes, materials and properties. The theory of burst, collapse and axial loading isdiscussed along with design policies and procedures. A thorough review of API specifications is performed along with a review of the theory behind these specifications and their limitations. Connections and special cases, including HPHT and sour service are discussed. A significant part of this course involves exercises and may involve self-paced activities (homework) outside the classroom schedule. Students should have a personal calculator and access to a computer with a spreadsheet software program and know how to enter formulas in the spreadsheet software.

Sub-Discipline                                                                        Well Planning & Design

Discipline                                                                                Drilling Engineering

Modality                                                                                 Classroom

Course Level                                                                          Skill

Course duration                                                                     5 Days

Course Objective

This course will focus on casing design, both from an engineering and an operation perspective. Design concepts will be covered for a wide range of straightforward, as well as hostile environments. The course will examine the nomenclature of casing design, manufacturing processes, material properties and material selection. The theory of burst, collapse, and axial loading will be discussed, along with design policies and procedures. Important API specifications and other industry standards will be discussed in order for the participants to become familiar with these documents. Connection and special cases, including HPHT and sour service, will be covered. Casing setting depths and depth design concepts will also be covered in detail.

A significant part of the course will involve exercises and self-paced (homework) activities which may be completed outside the classroom schedule. Participants should have a personal calculator and access to a computer with a spreadsheet software program. Participants will need to know how to enter formulas into their spreadsheet software.

This course will be delivered in a class-driven process. The instructor, along with the participants, will team together to set the pace of learning. Lectures interspersed with classroom discussion and exercises will be used to ensure understanding and integration of concepts needed to evaluate potential service requirements, give recommendations, and select the appropriate tubular. The exact schedule and depth of content covered during the course will be tailored to the interest and needs of the audience and may deviate from what is shown in the daily schedule.


Well designers, drilling engineers, well construction supervisors, engineering managers, drilling supervisors, directional drillers, and service company personnel needing an in-depth understanding of tubular design for well construction.


Participants will need to have a solid understanding of wellbore geometry, well construction, and basic mechanical concepts. The course will involve numerous calculations, as a result participant will need good math skills and a basic scientific calculator. Portable computers with a spreadsheet software will be used to allowparticipants to capture design formulas which are introduced in the class.


Day 1

Steel, Manufacturing, API, and ISO

Material and mechanical properties of steelAPI and ISO ratings and formulas

Tubular testing

Oil country tubular goods manufacturing

Day one of this course will begin with discussions of material and mechanical properties of steel, along with stress-strain and deformation that will lay the groundwork for an understanding of the limitations of published tubular ratings. Participants will get a chance to learn about API and ISO rating and tubular streng th formulas. Specific API and ISO topics that will be covered include API yield stress, Barlow Equation for tubular internal yield, casing thread leak resistance, collapse formulas, and tension. The day will end with participants learning about tubular manufacturing and testing.

Day 2

Connections, Sulfide Stress Cracking, and Corrosion Resistant Material Selection API and proprietary connectionsAPI

thread leak resistance

Sour service considerations

Corrosion resistant alloy (CRA) selection

Tubular connections and sour service conditions will be the focus of day two. Specific topics of API thread forms, marking and make-up considerations will be discussed in detail. Proprietary thread types will also be discussed, and students will get an opportunity to learn about the advantages and benefits of different thread form styles.

Hydrogen sulfide stress cracking mechanism will be explored. Corrosion, its effect on tubulars and guidelines for selection of appropriate materials for casing under different corrosive conditions will be explained.

Day 3

Triaxial Stress and Setting Depth Determination

Design principals and factorsLoad concepts

Triaxial stress Casing wear

Setting depth determination

On day three, the spreadsheet will be completed with formulas for calculating triaxial stress of various load states which casing may be exposed. Design factors and comparison between uni-axial and triaxial stress will be evaluated. Buckling of tubulars will be discussed, which will help as participants learn about effects of temperature change on tubulars. Casing wear mechanisms and some suggestions for management and design for effects of wear will be presented. Casing setting depth needed for well control integrity will finish the day.

Day 4

Service Life, Load Cases, and Storage Load cases

Base case Procurement Inspection

Running procedures

Service life models and load cases will be the focus of day four. Load cases, such as axial, burst, and collapse will be explained and load estimates for different situations will be evaluated.

Base case determination from which load changes are evaluated will be covered. Participants will learn about the planning, specifications, and quality assurance of procurement. The day will end with a discussion over inspection types, marking, and suggestions on running practices.

Day 5

Tubular Design Software and Comprehensive Casing Design Tubular design software

Final comprehensive casing design project

The last day of this course participants will learn about tubular design software and some of the ways which it can be used in well planning and casing design. The day will end with the participants breaking into teams and working on a final comprehensive casing design project.