Pressure Vessel Design ASME Guide

Overview of Pressure Vessel Design

Instructor’s Guide

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CONTACT INFORMATION ASME Headquarters Headquarters 1-800-THE-ASME ASME Professional Development 1-800-THE-ASME

Eastern Regional Office 8996 89 96 Burk Burke e Lak Lake e Roa Road d – Suit Suite e L10 L102 2 Burke, VA 22015-1607 703-978-5000 800-221-5536 703-978-1157 ( FA X )

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International Regional Office 1-800-THE-ASME You Youcan canalso alsofind findinformation informationon onthese these courses and all of ASME, including courses and all of ASME, includingASME ASME Professional Development, the Vice Professional Development, the Vice President Presidentof ofProfessional ProfessionalDevelopment, Development, and other contacts and other contactsat atthe theASME ASMEWeb Web site...... site...... http://www.asme.org http://www.asme.org

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CONTACT INFORMATION ASME Headquarters Headquarters 1-800-THE-ASME ASME Professional Development 1-800-THE-ASME

Eastern Regional Office 8996 89 96 Burk Burke e Lak Lake e Roa Road d – Suit Suite e L10 L102 2 Burke, VA 22015-1607 703-978-5000 800-221-5536 703-978-1157 ( FA X )

Southern Regional Office 1950 19 50 Stem Stemmo mons ns Free Freewa way y – Suit Suite e 506 5068 8 Dallas, TX 75207-3109 214-800-4900 800-445-2388 214-746-4902 (FAX)

Midwest Regional Office 1117 S. Milwaukee Avenue Building B, Suite 13 Libertyville, IL 60 60048-5258 847-680-5493 800-628-6437 847-680-6412 ( FA X )

Western Regional Office 119-C Paul Drive San Rafael, CA 94903-2022 415-499-1148 800-624-9002 415-499-1338 (FAX)

Northeast Regional Office 326 Clock Tower Commons Route 22 Brewster, NY 10509-9241 845-279-6200 800-628-5981 845-279-7765 ( FA X )

International Regional Office 1-800-THE-ASME You Youcan canalso alsofind findinformation informationon onthese these courses and all of ASME, including courses and all of ASME, includingASME ASME Professional Development, the Vice Professional Development, the Vice President Presidentof ofProfessional ProfessionalDevelopment, Development, and other contacts and other contactsat atthe theASME ASMEWeb Web site...... site...... http://www.asme.org http://www.asme.org

2

Overview of Pressure Vessel Design By: By: Vincent A. Carucci Carmagen Engineering, Inc.

Copyright © 1999 by

All Rights Reserved

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TABLE OF CONTENTS

Abstract………………………………………………………………… 5 Introduction…………………………..…………………………………6 Organizing Unit Responsibilities……………………………………..7 Instructor Guidelines and Responsibilities………………………….9 Overview of Pressure Vessel Design Outline/ Teaching Plan…………………………………………………………11 Instructor Notes……………………………………………………….13 Appendix A: Reproducible Overheads Appendix B: Course and Instructor Evaluation Form Appendix C: Continuing Education Unit (CEU) Submittal Form Course Improvement Form Instructor’s Biography Form

4

ABSTRACT

Pressure vessels are typically designed, fabricated, installed, inspected, and tested in accordance with the ASME Code Section VIII. Section VIII is divided into three separate divisions. This course outlines the main differences a mong the divisions. It then concentrates on and presents an overview of Division I. This course also discusses several relevant items that are not included in Division I.

5

INTRODUCTION

This Overview of Pressure Vessel Design course is part of the ASME International Career Development Series – an educational tool to help engineers and managers succeed in today’s business/engineering world. Each course in this series is a 4hour (or half-day) self-contained professional development seminar. The course material consists of a participant manual and an instructor’s guide. The participant manual is a self-contained text for students/participants, while the guide (this booklet) provides the instructional material designed to be presented by a local knowledgeable instructor with a minimum of preparation time. The balance of this instructor’s guide focuses on: 1. 2. 3.

Organizing Unit Responsibilities Instructor Guidelines and Responsibilities Comprehensive teaching materials which may be used “as is” or adapted to incorporate experiences and perspective of the instructor.

Welcome to the ASME International Career Development Series! We wish you all the best in your presentation, operation and delivery of this course.

6

7

8

9

10

Suggested Outline/Teaching Plan Time, min.

Major Interval 10

Class Segment Introduction

Sub-Segment Interval 5 5

25

General

10 10

Sub-Segment Introduction/Logistics Outline Module Module based primarily on the ASME Code Section VIII, Division 1. Divisions 2 and 3 will be briefly described Main Pressure Vessel Components Scope of ASME Code Section VIII Division 1 Division 2 Division 3 Structure of Section VIII, Division 1 •

Overheads/ Participant Pages OV – 1 Part. – 65 OV – 2 Part. – 65

OV – 3-9 Part. – 67 OV – 10-13 Part. – 75

• •

5 20

Materials of Construction

15

Material Selection Factors Strength Corrosion Resistance Resistance to Hydrogen Attack Fracture Toughness Fabricability Maximum Allowable Stress •

OV – 14 Part. –78 OV – 15-31 Part. – 79

• • • •

5 10

Exercise

10

10 55

Break Design

10 10

Material Selection Based On Fracture Toughness Design Conditions and Loadings Pressure Temperature Other Loadings Design for Internal Pressure Weld Joints Cylindrical Shells Heads Conical Sections Sample Problem Design for External Pressure and Compressive Stresses Cylindrical Shells Other Components Sample Problem •

OV – 32-34 Part. – 87 OV – 35-38 Part. – 91 OV – 39-43 Part. – 92

• •

25

•

OV – 44-55 Part. - 98

• • •

20

OV – 56-65 Part. – 109

• • •

11

Suggested Outline/Teaching Plan, continued Time, min.

Major Interval 10 - 50

Class Segment

Sub-Segment Interval

Major Break

Sub-Segment

Overheads/ Participant Pages

Lunch or Major Break

15

Exercise

15

Required Thickness for Internal Pressure

OV – 66-68 Part. - 118

50

Design (Cont’d.)

20

Reinforcement of Openings (Include Sample Problem) Flange Rating (Including Sample Problem) Flange Design

OV – 69-84 Part. – 119 OV – 85-90 Part. – 127 OV – 91-97 Part. – 131 OV – 98 Part. – 138

10 15

10 20

20

15

10

Break Other Design Considerations

Fabrication

Inspection and Testing

Closure

5

Maximum Allowable Working Pressure (MAWP)

10

Local Loads

10

Vessel Internals

10

Acceptable Welding Details

10

Postweld Heat Treatment (PWHT)Requirements

10

Inspection

5

Pressure Testing

10

Summary Questionnaire (fill in and collect) CEU Form (hand out – individual responsibility to return)

OV – 99 Part. – 139 OV – 100-102 Part. – 141 OV – 103-106 Part. – 143 OV – 107 Part. – 146 OV – 108-113 Part. – 148 OV – 114-115 Part. – 152 OV – 116 Part. - 155

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Overview of Pressure Vessel Design Instructor’s Personal Notes

OVERVIEW OF PRESSURE VESSEL DESIGN By: Vincent A. Carucci Carmagen Engineering, Inc .

1

Instructor’s Outline 1. Course discusses pressure vessel design and is introductory in nature.

Major Learning Points Course Introduction

2. Based on ASME Code Section VIII. 3. Preliminary emphasis is on Division 1 but Divisions 2 and 3 are highlighted. 4. Introduces several items that are not covered in the ASME Code.

13

Overview of Pressure Vessel Design Instructor’s Personal Notes Course Overview • General • Materials of Construction • Design • Other Design Considerations • Fabrication • Inspection and Testing 2

Instructor’s Outline 1. The objective: Provide a general knowledge of design requirements for pressure vessels.

Major Learning Points •

Establish course objectives.

•

Outline course content, a road map.

2. This is not a comprehensive course. It provides sufficient information for management personnel to have an overall understanding of this subject. Individuals having more detailed responsibility will receive a solid starting point to proceed further. 3. Review outline. 4. Establish schedule. 5. Participation is key: •

Questions

•

Discussion/interaction

14


Pressure Vessels • Containers for fluids under pressure • Used in variety of industries – Petroleum refining – Chemical – Power – Pulp and paper – Food 3

Instructor’s Outline

Major Learning Points

1. Describe what a pressure vessel is.

•

Define pressure vessels.

2. Note that pressure vessels are used in a wide variety of industries. They can be designed for a wide variety of conditions and in a broad range of sizes.

•

Identify wide variety of industrial applications.

15

Overview of Pressure Vessel Design Instructor’s Personal Notes Horizontal Drum on Saddle Supports Nozzle

A

Shell

Head

Head

Saddle Support (Sliding)

SaddleSupport (Fixed) A

SectionA-A

Figure 2.1 4

Instructor’s Outline 1. Use this and following overheads to describe main pressure vessel components and shapes.

Major Learning Points Main pressure vessel components and configurations.

2. Shell is primary component that contains pressure. Curved shape. 3. Vessel always closed by heads. 4. Components typically welded together. 5. Vessel shell may be cylindrical, spherical, or conical. 6. Multiple diameters, thicknesses or materials are possible. 7. Saddle supports used for horizontal drums. •

Spreads load over shell.

•

One support fixed, other slides.

16

Overview of Pressure Vessel Design Instructor’s Personal Notes Vertical Drum on Leg Supports Head

Shell

Nozzle

Head

Support Leg

5

Instructor’s Outline 1. Most heads are curved shape for strength, thinness, economy.

Figure 2.2

Major Learning Points Main pressure vessel components and shapes.

2. Semi-elliptical shape is most common head shape. 3. Small vertical drums typically supported by legs. •

Typically maximum 2:1 ratio of leg length to diameter.

•

Number, size, and attachment details depend on loads.

17


Tall Vertical Tower Nozzle Head

Trays

Shell

Nozzle

Cone

Nozzle Shell

Nozzle

6

Instructor’s Outline 1. Nozzles used for: •

Piping systems

•

Instrument connections

•

Manways

•

Attaching other equipment

Head Skirt Support

Figure 2.3


2. Ends typically flanged, may be welded. 3. Sometimes extend into vessel.

18


Vertical Reactor Inlet Nozzle Head

Upper Catalyst Bed

Shell

Catalyst Bed Support Grid

Lower Catalyst Bed Outlet Collector Head Outlet Nozzle Support Skirt

7

Instructor’s Outline 1. Skirt supports typically used for tall vertical vessels: •

Cylindrical shell

•

Typically supported from grade

Figure 2.4


2. General support design (not just for skirts) •

Design for weight, wind, earthquake.

•

Pressure not a factor.

•

Temperature also a consideration for material selection and thermal expansion.

19


Spherical Pressurized Storage Vessel Shell

Support Leg

Cross Bracing

Figure 2.5 8

Instructor’s Outline 1. Spherical storage vessels typically supported on legs.


2. Cross-bracing typically used to absorb wind and earthquake loads.

20

Overview of Pressure Vessel Design Instructor’s Personal Notes Vertical Vessel on Lug Supports

9

Instructor’s Outline 1. Vessel size limits for lug supports: •

1 – 10 ft diameter

•

2:1 to 5:1 height/diameter ratio

Figure 2.6

Major Learning Points Main pressure vessel components and configurations.

2. Vessel located above grade. 3. Lugs bolted to horizontal structure.

21

Overview of Pressure Vessel Design Instructor’s Personal Notes Scope of ASME Code Section VIII • Section VIII used worldwide • Objective: Minimum requirements for safe construction and operation • Division 1, 2, and 3

10

Instructor’s Outline 1. Section VIII is most widely used Code.

Major Learning Points Define scope of ASME Code Section VIII.

2. Assures safe design. 3. Three divisions have different emphasis.

22

Overview of Pressure Vessel Design Instructor’s Personal Notes Section VIII Division 1 • 15 psig < P ≤ 3000 psig • Applies through first connection to pipe • Other exclusions – Internals (except for attachment weld to vessel) – Fired process heaters – Pressure containers integral with machinery – Piping systems

11



1. Review scope of Division 1.

•

Scope of Division 1

2. Division 1 not applicable below 15 psig.

•

Exclusions from scope

3. Additional rules required above 3000 psig. 4. Items that are connected to pressure vessels not covered by Division 1, except for: •

Their effect on pressure part.

•

Welded attachment to pressure part.

23


Section VIII, Division 2, Alternative Rules • Scope identical to Division 1 but requirements differ – Allowable stress – Stress calculations – Design – Quality control – Fabrication and inspection

• Choice between Divisions 1 and 2 based on economics

12

Instructor’s Outline 1. Review differences between Divisions 1 and 2.

Major Learning Points Differences between Division 1 and 2.

2. Division 2 allowable membrane stress is higher. 3. Division 2 requires more complex calculations. 4. Division 2 does not permit some design details that are permitted in Division 1. 5. Division 2 requires more stringent material quality control, fabrication, and testing requirements.

24

Overview of Pressure Vessel Design Instructor’s Personal Notes Division 3, Alternative Rules High Pressure Vessels • Applications over 10,000 psi • Pressure from external source, process reaction, application of heat, combination of these • Does not establish maximum pressure limits of Division 1 or 2 or minimum limits for Division 3. 13

Instructor’s Outline 1. Review application of Division 3.

Major Learning Points Scope of Division 3

2. Newest Division of Section VIII and has least applicability. 3. After this point, this course only addresses Division 1 requirements when code-specific items are discussed.

25


Structure of Section VIII, Division 1

• Subsection A

– Part UG applies to all vessels

• Subsection B – Requirements based on fabrication method – Parts UW, UF, UB

• Subsection C – Requirements based on material class – Parts UCS, UNF, UHA, UCI, UCL, UCD, UHT, ULW, ULT

• Mandatory and Nonmandatory Appendices

14

Instructor’s Outline 1. Review Division 1 organization 2. Fabrication methods: •

Welded

•

Forged

•

Brazed

Major Learning Points Basic organizational structure of Division 1.

3. Material classes •

Carbon and low-alloy steel

•

Non-ferrous metals

•

High alloy steel

•

Cast iron

•

Clad and lined material

•

Ductile iron

•

Heat treated steels

•

Layered construction

•

Low-temperature material

4. Highlight several mandatory and nonmandatory appendices.

26


Material Selection Factors • Strength • Corrosion Resistance • Resistance to Hydrogen Attack • Fracture Toughness • Fabricability

15

Instructor’s Outline 1. ASME Code does not specify particular materials to use in each application. Owner must do this.

Major Learning Points Primary factors that influence pressure vessel material selection.

2. ASME Code specifies permitted materials and the requirements that these must meet.

27


Strength • Determines required component thickness • Overall strength determined by: – Yield Strength – Ultimate Tensile Strength – Creep Strength – Rupture Strength

16

Instructor’s Outline 1. Strength: Material’s ability to withstand imposed loading. 2. Higher strength material component.

→

Major Learning Points Material strength and pressure vessel design.

thinner

3. Describe properties that are used to define strength.

28


Corrosion Resistance • Deterioration of metal by chemical action • Most important factor to consider • Corrosion allowance supplies additional thickness • Alloying elements provide additional resistance to corrosion

17

Instructor’s Outline 1. Corrosion is thinning of metal. 2. Adding extra component thickness (i.e., corrosion allowance) is most common method to address corrosion.

Major Learning Points Importance of corrosion resistance in materials selection.

3. Alloy materials are used in services where corrosion allowance would be unreasonably high if carbon steel were used.

29


Resistance to Hydrogen Attack • At 300 - 400°F, monatomic hydrogen forms molecular hydrogen in voids • Pressure buildup can cause steel to crack • Above 600°F, hydrogen attack causes irreparable damage through component thickness 18

Instructor’s Outline 1. Low-temperature H 2 attack can cause cracking.

Major Learning Points Hydrogen attack can damage carbon and low-alloy steel.

2. Higher temperature H 2 attack causes through-thickness strength loss and is irreversible. 3. H2 attack is a function of H 2 partial pressure and design temperature. •

Increased alloy content (i.e., Cr) increases H 2 attack resistance.

•

Reference API-941 for “Nelson Curves.”

30

Overview of Pressure Vessel Design Instructor’s Personal Notes Brittle Fracture and Fracture Toughness • Fracture toughness: Ability of material to withstand conditions that could cause brittle fracture • Brittle fracture – Typically at “low” temperature – Can occur below design pressure – No yielding before complete failure 19

Instructor’s Outline 1. Describe brittle fracture as equivalent to dropping a piece of glass.

Major Learning Points Brittle fracture and its consequences.

2. Material selection must ensure that brittle fracture will not occur.

31

Overview of Pressure Vessel Design Instructor’s Personal Notes Brittle Fracture and Fracture Toughness, cont’d • Conditions required for brittle fracture – High enough stress for crack initiation and growth – Low enough material fracture toughness at temperature – Critical size defect to act as stress concentration 20

Instructor’s Outline 1. A brittle fracture will occur the first time the appropriate conditions occur.

Major Learning Points Three conditions that are required for a brittle fracture to occur.

2. Brittle fracture occurs without warning and is catastrophic.

32

Overview of Pressure Vessel Design Instructor’s Personal Notes Factors That Influence Fracture Toughness • Fracture toughness varies with: - Temperature - Type and chemistry of steel - Manufacturing and fabrication processes

• Other factors that influence fracture toughness:

21

Instructor’s Outline 1. Describe influence of material and temperature factors on fracture toughness.

- Arc strikes, especially if over repaired area - Stress raisers or scratches in cold formed thick plate

Major Learning Points Primary factors that influence material fracture toughness.

2. Other factors increase brittle fracture risk.

33


Charpy V-Notch Test Setup

Scale

Pointer

StartingPosition Hammer

h'

End of swing Specimen h'

Anvil

22

Instructor’s Outline 1. Charpy V-Notch test is most widely used measure of material fracture toughness.

Major Learning Points Charpy V-Notch testing.

2. Describe test set-up.

34

Overview of Pressure Vessel Design Instructor’s Personal Notes ASME Code and Brittle Fracture Evaluation • Components to consider – Shells – Manways – Heads – Reinforcing pads – Backing strips that remain in place

– Nozzles – Tubesheets – Flanges – Flat cover plates – Attachments essential to structural integrity that are welded to pressure parts

23

Instructor’s Outline 1. ASME Code contains brittle fracture evaluation procedure.

Major Learning Points Components to consider is ASME Code brittle fracture evaluation.

2. Review components to be included only items that relate to structural integrity of pressure-containing shell.

35


Temperatures to Consider • Minimum Design Metal Temperature (MDMT) – Lowest temperature at which component has adequate fracture toughness

• Critical Exposure Temperature (CET) – Minimum temperature at which significant membrane stress will occur

24

Instructor’s Outline 1. Describe the distinction between MDMT and CET. •

MDMT is a materialproperty.

•

CET is an environmental factor.

Major Learning Points Two temperatures to be considered in brittle fracture evaluation.

2. Important to understand this distinction.

36

Overview of Pressure Vessel Design Instructor’s Personal Notes Simplified ASME Evaluation Approach • Material specifications classified into Material Groups A through D • Impact test exemption curves – For each Material Group – Acceptable MDMT vs. thickness where impact testing not required

• If combination of Material Group and thickness not exempt, then must impact test at CET 25

Instructor’s Outline 1. Outline ASME procedure. 2. Details described in following overheads.

Major Learning Points Simplified ASME brittle fracture evaluation procedure.

37


Material Groups MATERIAL GROUP Curve A

Curve B

APPLICABLE MATERIALS •

A l l c a r b o n a n d l o w a l lo y s t e e l p l a t es , s t r u c t u ra l s h a p e s , a n d b a r s n o t listed in Curves B, C & D

•

S A - 2 1 6 G r . W C B & W C C , SA - 2 1 7 G r . W C 6 , i f n o r ma l i z e d a n d t e m p er e d or water-quenched and tempered

•

S A - 2 16 G r . W C A , i f n o r m al i z ed a n d t e m p e r ed o r w a t e r - q u e n c h e d a n d tempered

•

S A - 2 1 6 G r . W C B & W C C f o r m a x im u m t h i c k ne s s o f 2 i n . , if p r o d u c e d to fine grain practice and water-quenched and tempered

•

S A - 28 5 Gr . A & B

•

S A- 41 4 Gr . A

•

S A- 5 15 G r. 6 0

•

S A - 5 16 G r . 6 5 & 7 0 , i f n o t n o rm a l iz e d

•

Except for cast steels, all materials of Curve A if produced to fine grain practice and normalized which are not included in Curves C & D

•

A l l p i p e , f i tt i n g s , f o r g i n g , a n d t u b in g w h i c h a r e n o t i n c lu d e d i n C u r v e s C& D

Table 3.1 (Excerpt) 26

Instructor’s Outline 1. Materials are grouped based on common fracture toughness properties.

Major Learning Points Material group classifications for brittle fracture evaluations.

2. Groups A through D move from worst to best fracture toughness. 3. Point out several common materials. •

SA-516 Gr. 65 and 70 are Curve B if not normalized.

•

Most pipe, fittings and forgings are Curve B.

38


Material Groups, cont’d MATERIAL GROUP Curve C

Curve D

Bolting and Nuts

APPLICABLE MATERIALS • •

S A - 1 8 2 G r . 2 1 & 22 , i f n o r m a l i ze d a n d t e m pe r e d S A -3 02 G r. C & D

•

S A - 3 3 6 G r. F 2 1 & F 2 2 , i f n or m a l i z ed a n d t e m pe r e d

•

S A - 3 8 7 G r . 2 1 & 22 , i f n o r m a l i ze d a n d t e m pe r e d

• •

S A - 5 1 6 G r . 5 5 & 6 0 , i f n ot n o r m al i z e d S A -5 33 G r. B & C

•

S A -6 62 Gr . A

•

A l l m a t e r i a l o f C u r ve B i f p r o d u c e d t o f i n e g r ai n p r a c t i c e a n d normalized which are not included in Curve D

•

S A- 20 3

•

•

S A- 508 C l . 1

•

SA-612, if normalized

•

S A - 5 16 , i f n o r m a l i z e d

•

SA-662, if normalized

•

S A- 524 C l . 1 & 2

•

S A- 7 3 8 G r . A

•

S e e F i g u r e U C S - 6 6 o f t h e A S M E C od e S e c t i o n V I I I , D i v . 1 , f o r i m p ac t

S A - 537 C l. 1, 2 & 3

test exemption temperatures for specified material specifications

Table 3.1 (Excerpt) 27

Instructor’s Outline 1. Identify other common materials. •

SA-516 Gr. 55 and 60 are Curve C if not normalized.

•

SA-516 (all grades) is Curve D if normalized.

Major Learning Points Material group classifications for brittle fracture evaluations.

2. Highlight points. •

Lower strength grades of same specification have better fracture toughness.

•

Normalization improves fracture toughness.

39


Impact Test Exemption Curves for Carbon and Low-Alloy Steel 140 120 100 F , e r u t a r e p m e T l a t e M n g i s e D m u m i n i M

B

A

80 60

C 40 D

20 0 -20 -40 -55 -60 -80

Impact testing required 0.394

1

2

3

4

5

Nominal Thickness, in. (Limited to 4 in. for Welded Construction)

Figure 3.1 28

Instructor’s Outline 1. Describe relationship between Material Group, component thickness, and MDMT.

Major Learning Points Impact test exemption curves.

2. Impact testing not required if point is at or below curve (i.e., OK if MDMT ≤ CET). 3. Example: 1.5 in. thick Group B material does not require impact testing if CET ≥ 50° F. 4. If not exempt, must impact test material at CET. 5. “Exemption” means there is enough experience that material has adequate fracture toughness without need for further testing.

40


Additional ASME Code Impact Test Requirements • Required for welded construction over 4 in. thick, or nonwelded construction over 6 in. thick, if MDMT < 120 ° F • Not required for flanges if temperature ≥ -20 °F • Required if SMYS > 65 ksi unless specifically exempt

29

Instructor’s Outline 1. Review additional requirements.

Major Learning Points Additional impact test requirements.

2. Note that most flanges will not require impact testing.

41


Additional ASME Code Impact Test Requirements, cont’d • Not requir required ed for impac impactt tested tested low temperature steel specifications – May use at impact impact test temperature temperature

• 30°F MDMT reduction reduction if PWHT P-1 steel and not required by code • MDMT MDMT reduction reduction if calcul calculated ated stress stress < allowable stress 30

Instructor’s Outline 1. Revi Review ew addition additional al requirem requirements ents..

Major Learning Points Additional impact test requirements.

2. PWHT PWHT red reduc uces es MDMT MDMT by 30° F provided PWHT not required by Code and resulting MDMT ≥ -55° F. 3. Can take take MDMT MDMT cred credit it if comp compone onent nt thickness greater than needed (i.e., calculated stress < allowable stress).

42


Fabricability • Ease Ease of const construc ructio tion n • Any required required special special fabrica fabrication tion practic practices es • Material Material must be weldabl weldable e

31

Instructor’s Outline Describe fabricability.

Major Learning Points Definition of fabricability. fabricability.

43


Maximum Allowable Stress • Stress: Force per unit unit area that resists resists loads loads induced by external forces • Pressure Pressure vessel vessel components components design designed ed to keep stress within safe operational limits • Maximum Maximum allowable allowable stress: stress: – Includes safety margin margin – Varies with temperature temperature and material material

• ASME maximu maximum m allowable allowable stress stress tables for permitted material specifications 32

Instructor’s Outline 1. Discus Discuss s the use use of allo allowab wable le stres stress s in determining vessel component design.


Description of allowable stress.

•

ASME Code allowable stress tables

2. Sectio Section n II, II, Part Part D, D, Append Appendix ix I contains allowable stress criteria for materials other than bolting. 3. Section Section II, Part D contain contains s al allowab lowable le stress tables.

44


Maximum Allowable Stress, cont’d ALLOWABLE STRESS IN TENSION FOR CARBON AND LOW-ALLOY STEEL Nominal P -N o. G ro u p N o . M i n. Y ie l d Min. Tensile Composition (ksi) (ksi) Carbon Steel Plates and Sheets SA-515 55 C-Si 1 1 30 55 60 C-Si 1 1 32 60 65 C-Si 1 1 35 65 70 C-Si 1 2 38 70 Spec No.

SA-516

Grade

55 60 65 70

C-Si C-Mn-Si C-Mn-Si C-Mn-Si

Plate - Low Alloy Steels SA-387 2 Cl.1 1/2Cr-1/2Mo 2 Cl.2 1/2Cr-1/2Mo 12 Cl.1 1Cr-1/2Mo 12 Cl.2 1Cr-1/2Mo 11 Cl.1 1 1/4Cr-1/2Mo-Si 11 Cl.2 1 1/4Cr-1/2Mo-Si 22 Cl.1 2 1/4Cr-1Mo 22 Cl.2 2 1/4Cr-1Mo

1 1 1 1

1 1 1 2

30 32 35 38

55 60 65 70

3 3 4 4 4 4 5 5

1 2 1 1 1 1 1 1

33 45 33 40 35 45 30 45

55 70 55 65 60 75 60 75

ASME Maximum Allowable Stress (Table 1A Excerpt) Figure 3.2 33

Instructor’s Outline 1. Describe information contained in first section of table.

Major Learning Points ASME Code allowable stress tables.

2. Information is grouped by material chemistry and material form.

45


Maximum Allowable Stress, cont’d ALLOWABLE STRESS IN TENSION FOR CARBON AND LOW ALLOY STEEL Max Allowable Stress, ksi (Multiply by 1,000 to Obtain psi) for Metal Temperature, °F, Not Exceeding

2.5 2.5 2.5 2.5

1050 Carbon -----

Spec No. 1100 1150 1200 Steel Plates and Sheets ---SA-515 ---SA-515 ---SA-515 ---SA-515

4.5 4.5 4.5 4.5

2.5 2.5 2.5 2.5

-----

-----

9.2 9.2 11.3 11.3 9.3 9.3 10.8 11.4

5.9 5.9 7.2 7.2 6.3 6.3 8.0 7.8

Plate-Low Alloy Steels (Cont'd) ----SA-387 ----SA-387 4.5 2.8 1.8 1.1 SA-387 4.5 2.8 1.8 1.1 SA-387 4.2 2.8 1.9 1.2 SA-387 4.2 2.8 1.9 1.2 SA-387 5.7 3.8 2.4 1.4 SA-387 5.1 3.2 2.0 1.2 SA-387

650

700

750

800

850

900

950

1000

13.8 15.0 16.3 17.5

13.3 14.4 15.5 16.6

12.1 13.0 13.9 14.8

10.2 10.8 11.4 12.0

8.4 8.7 9.0 9.3

6.5 6.5 6.5 6.5

4.5 4.5 4.5 4.5

13.8 15.0 16.3 17.5

13.3 14.4 15.5 16.6

12.1 13.0 13.9 14.8

10.2 10.8 11.4 12.0

8.4 8.7 9.0 9.3

6.5 6.5 6.5 6.5

13.8 17.5 13.8 16.3 15.0 18.8 15.0 17.7

13.8 17.5 13.8 16.3 15.0 18.8 15.0 17.2

13.8 17.5 13.8 16.3 15.0 18.8 15.0 17.2

13.8 17.5 13.8 16.3 15.0 18.8 15.0 16.9

13.8 17.5 13.4 15.8 14.6 18.3 14.4 16.4

13.3 16.9 12.9 15.2 13.7 13.7 13.6 15.8

-----

-----

SA-516 SA-516 SA-516 SA-516

ASME Maximum Allowable Stress (Excerpt), cont'd Figure 3.2, cont'd 34

Instructor’s Outline 1. Review allowable stress vs. design temperature.

Major Learning Points ASME Code allowable stress tables.

2. Most ferritic materials have a constant allowable stress at temperatures through 650°F.

46

Overview of Pressure Vessel Design Instructor’s Personal Notes Material Selection Based on Fracture Toughness Exercise 1 • • • • • • • •

New horizontal vessel CET = - 2°F Shell and heads: SA-516 Gr. 70 Heads hemispherical: ½ in. thick Cylindrical shell: 1.0 in. thick No impact testing specified Is this correct? If not correct, what should be done?

35



1. This independent Exercise gives the Participants practice in material selection based on fracture toughness.

Participant Exercise 1 covering fracture toughness.

2. Review the given information together. 3. Allow approximately 10 minutes for the Participants to solve the problem. Then review the solution with them.

47


Exercise 1 - Solution • Must assume SA-516 Gr. 70 not normalized. Therefore, Curve B material (Ref. Table 3.1). • Refer to Curve B in Figure 3.1. – ½ in. thick plate for heads: MDMT = -7° F – ½ in. thick plate exempt from impact testing since MDMT < CET

• 1in. shell plate: MDMT = +31°F – Not exempt from impact testing

36

Instructor’s Outline 1. Review difference between normalized and non-normalized material with respect to fracture toughness.

Major Learning Points Solution to Participant Exercise.

2. Review MDMT determination in each case. 3. Note difference between MDMT and CET in each case.

48

Overview of Pressure Vessel Design Instructor’s Personal Notes Exercise 1 - Solution, cont’d • One approach to correct: Impact test 1 in. plate at -2°F. If passes, material acceptable. • Another approach: Order 1 in. plate normalized – Table 3.1: normalized SA-516 is Curve D material – Figure 3.1: 1in. thick Curve D, MDMT = -30 °F – Normalized 1 in. thick plate exempt from impact testing

37

Instructor’s Outline 1. Review possible solutions for the 1 in. plate.

Major Learning Points Solution to Participant Exercise.

49


Exercise 1 - Solution, cont’d • Choice of option based on cost, material availability, whether likely that 1in. thick nonnormalized plate would pass impact testing

38

Instructor’s Outline 1. Review rationale for which option to select.

Major Learning Points Solution to Participant Exercise 1.

50


Design Conditions and Loadings • Determine vessel mechanical design • Design pressure and temperature, other loadings • Possibly multiple operating scenarios to consider • Consider startup, normal operation, anticipated deviations, shutdown 39

Instructor’s Outline 1. Review conditions to be considered. 2. Worst case operating scenario determines mechanical design.

Major Learning Points Design conditions and loadings to be considered in pressure vessel mechanical design.

51


Design Pressure PT = Design Pressure at Top of Vessel

γ = Weight Density of Liquid in Vessel

H = Height of Liquid

PBH = Design Pressure of Bottom Head

Figure 4.1 40

Instructor’s Outline 1. May have internal of external pressure, or both at different times.

Major Learning Points Design pressure as a mechanical design condition.

2. Must have margin between maximum operating pressure at top of vessel and design pressure. 3. Hydrostatic pressure of operating liquid (if present) must be considered at corresponding vessel elevation.

52

Overview of Pressure Vessel Design Instructor’s Personal Notes Temperature Zones in Tall Vessels Section 4 (T-Z)

Section 3 (T-Y )

Section 2 (T-X)

Section 1 (T) F SupportSkirt Grade

Figure 4.2 41

Instructor’s Outline 1. Margin required between operating temperature and design temperature.

Major Learning Points Design temperature as a mechanical design condition.

2. Maximum design temperature needed to determine allowable stress and thermal expansion considerations. 3. CET needed for material selection considering brittle fracture. 4. There may be a wide temperature variation between the bottom and top of a tall tower.

53


Additional Loadings • Weight of vessel and normal contents under operating or test conditions • Superimposed static reactions from weight of attached items (e.g., motors, machinery, other vessels, piping, linings, insulation) • Loads at attached internal components or vessel supports • Wind, snow, seismic reactions 42

Instructor’s Outline 1. Highlight other loads that must be considered in the mechanical design.

Major Learning Points Loadings other than pressure and temperature must also be considered.

2. These other loads may govern the mechanical design in local areas.

54


Additional Loadings, cont’d • Cyclic and dynamic reactions caused by pressure or thermal variations, equipment mounted on vessel, and mechanical loadings • Test pressure combined with hydrostatic weight • Impact reactions (e.g., from fluid shock) • Temperature gradients within vessel component and differential thermal expansion between vessel components 43

Instructor’s Outline 1. Review these additional other loads.

Major Learning Points Additional other loadings to consider.

55


Weld Joint Categories C

C

C A

A

B

D B

A

C

B

A D

C

D

A

D

B

B

D

A C

Figure 4.3 44

Instructor’s Outline 1. Review the ASME Code Weld Joint Categories.

Major Learning Points ASME Code defines welded joints by category.

2. Only specific weld types may be used in each category.

56


Weld Types Buttjointsasattainedby double-weldingorbyother meanswhichwillobtainthe samequalityofdeposited weldmetalon theinsideand outsideweldsurface.

1

Backingstrip,ifused,shall beremovedafter completionofweld. Single-weldedbutt jointwith backingstrip which remainsinplaceafterwelding.

2

Forcircumferential joint only

3

Single-weldedbuttjoint withoutbackingstrip.

4

Double-fullfilletlapjoint.

5

Single-fullfilletlapjointwithplugwelds.

6

Single-fullfilletlapjointwithoutplugwelds.

Figure 4.4 45

Instructor’s Outline 1. Review the different weld types. 2. Limited applications for Types 3 through 6.

Major Learning Points ASME Code defines specific weld types that may be used.

57

Overview of Pressure Vessel Design Instructor’s Personal Notes Weld Joint Efficiencies Joint Type

Acceptable Joint Categories

Degree of Radiographic Examination Full

Spot

None

1

A, B, C, D

1.00

0.85

0.70

2

A, B, C, D (See ASME Code for limitations)

0.90

0. 80

0.65

3

A, B, C

NA

NA

0.60

4

A, B, C (See ASME Code for limitations)

NA

NA

0.55

5

B, C (See ASME Code for limitations)

NA

NA

0.50

6

A, B, (See ASME Code for limitations)

NA

NA

0.45

Figure 4.5 46

Instructor’s Outline 1. Weld joint efficiency, E, is a measure of weld quality and accounts for stress concentrations.

Major Learning Points Weld joint efficiency vs. Joint Type, Category, Radiographic Examination.

2. E is needed in component thickness calculations. 3. Review information in table. 4. Note that corrosion allowance was previously discussed.

58


Summary Of ASME Code Equations Part

Thickness, tp , in.

Pressure, P, psi

Pr − 0.6P

r

+ 0.6t

Spherical shell

Pr 2SE1 − 0.2P

r

2SEt + 0.2t

2: 1 Semi - Elliptical head

PD

2SEt

2SE − 0.2P

D + 0.2t

Cylindrical shell

Torispherical head with 6% knuckle

SE1

P(r

+ 0.6t) tE1

P(r

+ 0.2t ) 2tE

P(D + 0.2t ) 2tE

0.885PL

SEt

P (0.885L + 0.1t )

SE − 0.1P

0.885L + 0.1t

tE

2SEt cos α

P(D + 1.2t co s α)

D + 1.2t co s α

2tE cos α

PD Conical Section ( α = 30°)

SE1t

Stress, S, psi

2 cos α (SE

− 0.6P)

Figure 4.6 47

Instructor’s Outline 1. Circumferential stress governs minimum required component thickness in most cases.

Major Learning Points ASME Code equations for various components under internal pressure.

2. Longitudinal stress may govern local thickness in some cases (e.g., under wind or earthquake loads). 3. Review ASME Code equations for internal pressure design. •

May calculate required thickness, permitted pressure, component stress.

•

Must account for corrosion allowance.

59

Overview of Pressure Vessel Design Instructor’s Personal Notes Typical Formed Closure Heads t

t R sf

sf

ID

ID

Flanged

Hemispherical t t

h sf

h

Elliptical

α

sf Flanged and Dished (torispherical)

t

t

α

sf r ID

ID

Conical

48

Instructor’s Outline 1. Review the different head types. 2. The 2:l semi-elliptical head is the most common.

Toriconical

Figure 4.7

Major Learning Points Different types of closure heads may be used.

60


Hemispherical Head to Shell Transition th

l

th t r a P r e n n i h T

≥ 3y

t r a P r e n n i h T

l ≥ 3y Tangent Line

y

Length of required taper, l, may include the width of the weld ts

y

ts

Figure 4.8 49



1. Required thickness of a hemispherical head is about half that of the connected cylindrical shell.

Thickness transition at a hemispherical head.

2. Must have a tapered thickness transition in the head to end up matching the shell thickness.

61


Sample Problem 1 Hemispherical

4' - 0" 60' - 0"

DESIGN INFORMATION Design Pressure = 250 psig Design Temperature = 700°F Shell and Head Material is SA-515 Gr. 60 Corrosion Allowance = 0.125" Both Heads are Seamless Shell and Cone Welds are Double Welded and w ill be Spot Radiographed The Vessel is in All Vapor Service Cylinder Dimensions Shown are Inside Diameters

10' - 0"

6' - 0" 30' - 0"

2:1 Semi-Elliptical

Figure 4.9 50

Instructor’s Outline 1. Sample Problem 1 illustrates calculation of required shell and head thicknesses for internal pressure.

Major Learning Points Sample Problem to illustrate calculation of required thickness for internal pressure.

2. Review the given information. 3. Review the problem solution with the Participants.

62

Overview of Pressure Vessel Design Instructor’s Personal Notes Sample Problem 1 - Solution • Required thickness for internal pressure of cylindrical shell (Figure 4.6):

tp

=

Pr SE1 − 0. 6P

• Welds spot radiographed, E = 0.85 (Figure 4.5) • S = 14,400 psi for SA- 515/Gr. 60 at 700°F (Figure 3.2) • P = 250 psig 51

Instructor’s Outline 1. Review the relevant equation for a cylindrical shell.

Major Learning Points Sample Problem 1 solution.

2. Note the sources used for the various parameters.

63


Sample Problem 1 Solution, cont’d • For 6 ft. - 0 in. shell

× 72 + 0.125 = 36.125 in. Pr 250 × 36.125 = tp = − SE1 0.6P 14,40 0 × 0.85 − 0.6 × 25 0 = 0.747 in. r = 0.5D + C = 0.5

t = tp + c = 0.747 + 0.125 t = 0.872 in., including corrosion allowance 52

Instructor’s Outline 1. The corrosion allowance must be added to obtain the inside radius.


2. The corrosion allowance must be added to the calculated thickness.

64

Overview of Pressure Vessel Design Instructor’s Personal Notes Sample Problem 1 Solution, cont’d • For 4 ft. - 0 in. shell r = 0.5

× 48 + 0.125 = 24.125 in. tp

=

250 × 24.125 14,400 × 0.85 − 0.6 × 250

= 0.499 in.

t = 0.499 + 0.125 t = 0.624 in., including corrosion allowance 53

Instructor’s Outline 1. The calculation is repeated for the other cylindrical shell section.


65


Sample Problem 1 Solution, cont’d Both heads are seamless, E = 1.0. Top Head - Hemispherical (Figure 4.6) r = 24 + 0.125 = 24.125 in.

tp

=

Pr 2SE1 − 0.2P

=

25 0 × 24.125 2 × 14,400

× 1 − 0.2 × 25 0

= 0.21 in.

t = tp + c = 0.21 + 0.125 t = 0.335 in., including corrosion allowance 54

Instructor’s Outline 1. Review the relevant equation for a hemispherical head.


2. Note the sources for the relevant parameters and how corrosion allowance is accounted for.

66


Sample Problem 1 Solution, cont’d • Bottom Head - 2:1 Semi-Elliptical (Figure 4.6) D = 72 + 2

tp

=

× 0.125

PD 2SE − 0.2P

=

= 72.25 in.

250 2 × 14,400

× 72.25 = 0.628 in. × 1 − 0.2 × 250

t = 0.628 + 0.125 t = 0.753 in., including corrosion allowance

55

Instructor’s Outline 1. Review the relevant equation for a semi-elliptical head.


2. Note the sources for the relevant parameters and how corrosion allowance is accounted for.

67


Design For External Pressure and Compressive Stresses • Compressive forces caused by dead weight, wind, earthquake, internal vacuum • Can cause elastic instability (buckling) • Vessel must have adequate stiffness – Extra thickness – Circumferential stiffening rings

56



1. Buckling of a shell under external pressure or compressive forces is analogous to column buckling under a compressive force.

Different procedures are used to design for external pressure or compressive loads.

2. Addition of stiffener rings reduces effective buckling length.

68


Design For External Pressure and Compressive Stresses, cont’d • ASME procedures for cylindrical shells, heads, conical sections. Function of: – Material – Diameter – Unstiffened length

– Temperature – Thickness

57

Instructor’s Outline 1. Highlight the main parameters that affect buckling strength.

Major Learning Points Parameters that affect compressive strength.

2. ASME Code has design procedure for each type of shell or head.

69


Stiffener Rings Moment Axis of Ring h/3

L

L

L

L

L

L

L

L

L

L

h/3 h = Depth of Head

Figure 4.10 58

Instructor’s Outline 1. Stiffener rings reduce the buckling length of a shell and may be either inside or outside.

Major Learning Points Use and location of stiffener rings.

2. Stiffener rings are not used for heads.

70


Sample Problem 2 DESIGN INFORMATION Design Pressure = Full Vacuum Design Temperature = 500°F Shell and Head Material is SA-285 Gr. B, Yield Stress = 27 ksi Corrosion Allowance = 0.0625" Cylinder Dimension Shown is Inside Diameter

4'-0"

150' - 0"

2:1 Semi-Elliptical (Typical)

Figure 4.11 59



1. Sample Problem 2 illustrates procedure for calculation of required cylindrical shell thickness for external pressure.

Sample Problem to illustrate calculation of required cylindrical shell thickness for external pressure.

2. The problem does not cover all aspects of the general procedure since it is geometry-specific. 3. Review the given information. 4. Review the problem solution with the participants.

71


Sample Problem 2 - Solution • Calculate L and Do of cylindrical shell. L = Tangent Length + 2 × 1/3 (Head Depth) L = 150 × 12 + 2/3 × (48/4) = 1,808 in. Do = 48 + 2 × 7/16 = 48.875 in. • Determine L/Do and Do /t Account for corrosion allowance: t = 7/16 – 1/16 = 6/16 = 0.375 in. Do /t = 48.875 / 0.375 = 130 L/Do = 1808 / 48.875 = 37 60

Instructor’s Outline 1. Corroded shell diameter and thickness are used in the calculations.


2. The unstiffened length of the shell must include part of the head depth.

72


Sample Problem 2 Solution, cont’d • Determine A. • Use Figure 4.12, Do /t, and L/Do. Note:

If L/Do > 50, use L/Do = 50. For L/Do < 0.05, use L/Do = 0.05

61

Instructor’s Outline 1. Factor A is determined based only on geometry.


2. Note the source of Factor A.

73


Sample Problem 2 Solution, cont’d A = 0.000065

Do/t = 100

1 0 0 9 0 8 . 7

D o/t = 125

Do /t = 130

6

D o/t = 150

5 4

D /t = 200

3

o

D o/t = 250 D o/t = 300 0 . 0 5

0 0 0 0 . . . . 0 5 0 5 4 3 3 2

0 0 0 0 0 0 0 0 8 0 0 = 1 ,0 = 4 t = 5 t = 6 / t / / / t = / t D o D o D o D o D o 0 0 0 0 0 0 0 . 0 . 0 . 0 . . 0 . . . . . . 0 . 5 . 0 . 5 . 0 8 6 4 2 0 9 8 7 6 5 4 3 3 2 2 1 1 1 1 1

2 1 0 0 0 0 . 0 . 8 . 6 . 4 . 2 . 2 1 1 1 1

Length + Outside Diameter = L/D o

L/Do = 37

Factor A Figure 4.12 62

Instructor’s Outline 1. Note how Factor A is determined from these curves.


2. After determine Factor A, go to applicable material chart.

74


Sample Problem 2 Solution, cont’d 20,000 GENERAL NOTE: See Table CS-1 for tabular values

18,000 16,000

up to 300°F 500°F

14,000

700°F

12,000

800°F

10,000

B

9,000 R

900°F

O

8,000 T C A

7,000 F

E=29.0 x 106

6,000

E=27.0 x 106

5,000

E=24.5 x 106 E=22.8 x 106

4,000

E=20.8 x 106

3,500 3,000 2,500 2,000

2 .00001

3 4 5 6 789 .0001

A=0.000065

63

Instructor’s Outline 1. Different material charts are used for different material types. This is chart used for most carbon and lowalloy steels.

2

3

4

5 6 789

2

3

4 5 6789

.001

2

3

4

.01

5 6 789 .1

FACTOR A

Factor B Figure 4.13


2. If A is under curves: •

Move up to intersect with temperature line.

•

Move right to get B.

•

B is then used to calculate allowable external pressure.

3. Since A is to left of curves in our case, must use alternate procedure.

75


Sample Problem 2 Solution, cont’d • Calculate maximum allowable external pressure

Pa

=

2AE 3(Do / t )

Where: E = Young's modulus of elasticity E = 27 × 106 psi (Figure 4.13) at T = 500°F P a = 9 psi 64

Instructor’s Outline 1. Pa is calculated using indicated equation because A is not under curves.


2. Must use E from curves at design temperature.

76


Sample Problem 2 Solution, cont’d Since Pa < 15 psi, 7/16 in. thickness not sufficient • Assume new thickness = 9/16 in., corroded thickness L = 1/2 in.

Do t

=

48. 875 0. 5

A = 0.000114

Pa

=

= 97 .75

L Do

2 × 0.000114 × 27 × 106 3 × 130. 33

= 3 7 (as before)

= 15. 7 psi

65

Instructor’s Outline 1. Since P a < 15 psi, must either increase shell thickness or add stiffeners to decrease L.


2. Problem illustrates results if increase thickness. 3. Choice of whether to increase thickness or add stiffeners depends on cost.

77


Exercise 2 - Required Thickness for Internal Pressure • • • • • • • •

Inside Diameter - 10’ - 6” Design Pressure - 650 psig Design Temperature - 750°F Shell & Head Material - SA-516 Gr. 70 Corrosion Allowance - 0.125 in. 2:1 Semi-Elliptical heads, seamless 100% radiography Vessel in vapor service

66



1. This independent Exercise gives the Participants practice in determining required vessel thicknesses for internal pressure.

Participant Exercise 2 covering required thickness for internal pressure.

2. Review the given information together. 3. Allow approximately 15 minutes for the Participants to solve the problem. Then review the solution with them. 4. Note that this Exercise may be skipped and assigned as homework if available class time is an issue.

78


Exercise 2 - Solution • For For sh shell ell

tp

=

SE 1

Pr − 0 .6P

P = 650 psig r = 0.5 × D + CA = (0.5 × 126) + 0.125 = 63.125 in. • S = 16,600 16,600 psi, Figure Figure 3.3 for SA-516 SA-516 Gr. 70 • E = 1.0, Figure Figure 4.8 for for 100% radiograp radiography hy

tp

=

650 × 63.125 = 2.53 in. (16,600 ×1 .0 ) − (0 .6 × 650)

67

Instructor’s Outline 1. Note the relevant relevant equatio equation n for for the the cylindrical shell and the appropriate parameters.

Major Learning Points Exercise 2 solution.

2. Note Note how corr corrosi osion on allo allowan wance ce is accounted for.

79


Exercise 2 - Solution, cont’d Add corrosion allowance tp = 2.53 + 0.125 = 2.655 in. • For For the the head heads s tp

=

tp

PD 2 SE − 0.2P

=

650 (126 × 0 .9) + 0 . 250 = 2 .23in. (2 × 16, 600) − (0 . 2 × 650 )

Add corrosion allowance 68

Instructor’s Outline 1. Note the relevant relevant equatio equation n for for the the heads and the appropriate parameters.

tp = 2.23 + 0.125 = 2.355 in.

Major Learning Points Exercise 2 solution.

2. Note Note how corr corrosi osion on allo allowan wance ce is accounted for.

80


Reinforcement of Openings • Simplifi Simplified ed ASME ASME rules - Area Area replace replacement ment • Metal Metal used to to replace replace that that removed removed:: -

Must be equivalent in metal area Must be adjacent to opening

69

Instructor’s Outline 1. Simplifie Simplified d ASME ASME rules rules do not require require stress calculations. Use “area replacement” approach.

Major Learning Points Openings must be reinforced to account for metal removed.

2. Metal Metal remove removed d must must be be replac replaced ed by equivalent metal.

81


Cross Sectional View of Nozzle Opening Dp tn

te

2.5t or 2.5t n + te Use smaller value

t

2.5t or 2.5t n Use smaller value

Rn

t rn

tr

c

h

d

d or R n + tn + t

d or R n + tn + t

Uselarger value

Uselargervalue

For nozzle wall inserted through the vessel wall

For nozzle wall abutting the vessel wall

Figure 4.14 70

Instructor’s Outline 1. Review Review cross cross-s -sec ectio tiona nall view view of region and associated nomenclature. 2. Note the differen differentt areas areas involved involved in the calculations and the “reinforcement zone” in the nozzle and shell.

Major Learning Points Region near opening and nomenclature.

82


Nozzle Design Configurations (a) Full Penetration Weld With Integral Reinforcement

(a -1 )

(a -2 )

(a -3 )

Separate ReinforcementPlates Added

(b )

( c)

( d)

(e)

Full Penetration Welds to Which Separate Reinforcement Plates May be Added

(f-1)

(f -3)

(f-2) (f-4)

(g)

Self - Reinforced Nozzles

71

Instructor’s Outline 1. Note Note the differ different ent nozz nozzle le desi design gn details that may be used.

Figure 4.15

Major Learning Points Typical nozzle configurations.

2. The actu actual al detai detaill used used in each each case case depends on the design conditions and the needed reinforcement.

83


Additional Reinforcement • Necessary if insufficient excess thickness • Must be located within reinforcement zone • Allowable stress of reinforcement pad should be ≥ that of shell or head • Additional reinforcement sources – Pad – Additional thickness in shell or lower part of nozzle 72

Instructor’s Outline 1. The method used to provide additional reinforcement depends on the particular situation.

Major Learning Points Requirements for additional reinforcement.

2. The ASME Code specifies circumstances where nozzle reinforcement evaluation is not needed. The opening is considered to be “inherently” reinforced in these cases.

84


Sample Problem 3 DESIGN INFORMATION Design Pressure = 300 psig Design Temperature = 200°F Shell Material is SA-516 Gr. 60 Nozzle Material is SA-53 Gr. B, Seamless Corrosion Allowance = 0.0625" Vessel is 100% Radiographed Nozzle does not pass through Vessel Weld Seam

NPS 8 Nozzle (8.625" OD) 0.5" Thick

0.5625" Thic k Shell, 48" Inside Diameter

Figure 4.16 73

Instructor’s Outline 1. Sample Problem 3 illustrates evaluation of an opening for adequate reinforcement.

Major Learning Points Sample Problem to illustrate evaluation of nozzle reinforcement.


85

Overview of Pressure Vessel Design Instructor’s Personal Notes Sample Problem 3 - Solution • Calculate required reinforcement area, A A = dtrF Where:

d =Finished diameter of circular opening, or finished dimension of nonradial opening in plane under consideration, in. tr = Minimum required thickness of shell using E = 1.0, in. F = Correction factor, normally 1.0 74

Instructor’s Outline 1. Required replacement area is based on the cross-sectional area removed.


2. Calculated using the required shell thickness, not the actual.

86


Sample Problem 3 - Solution, cont’d • Calculate diameter, d. d = Diameter of Opening – 2 (Thickness + Corrosion Allowance) d = 8.625 – 1.0 + .125 = 7.750 in. • Calculate required shell thickness, tr (Figure 4.6) tr = 0.487 in. • Assume F = 1.0 75

Instructor’s Outline 1. Corrosion allowance is accounted for.


2. tr is calculated using the appropriate shell equation.

87


Sample Problem 3 - Solution, cont’d • Calculate A A = dtr F A = (8.625 - 1.0 + 0.125) × 0.487 × 1 = 3.775 in.2 • Calculate available reinforcement area in vessel shell, A 1, as larger of A 11 or A12 A11 = (Elt - Ftr)d 76

Instructor’s Outline 1. Required area is calculated using the previously calculated parameters.

A12 = 2 (Elt-Ftr)(t + tn)


2. Two equations must be checked to determine the reinforcement area available in the shell.

88


Sample Problem 3 - Solution, cont’d Where :

E l = 1.0 when opening is in base plate away from welds, or when opening passes through circumferential joint in shell (excluding head to shell joints). E l = ASME Code joint efficiency when any part of opening passes through any other welded joint. F = 1 for all cases except integrally reinforced nozzles inserted into a shell or cone at angle to vessel longitudinal axis. See Fig. UG-37 for this special case. tn = Nominal thickness of nozzle in corroded condition, in. 77

Instructor’s Outline Review the relevant parameters.


89


Sample Problem 3 - Solution, cont’d A 11 = (Elt - Ftr)d = (0.5625 - 0.0625 - 0.487) × 7.75 = 0.1 in.2 A 12 = 2 (Elt - Ftr ) (t + t n) = 2(0.5625-0.0625-0.487) × (0.5625-0.0625+0.5 -0.0625) = 0.0243 in. 2 Therefore, A1 = 0.1 in. 2 available reinforcement in shell 78

Instructor’s Outline Available shell reinforcement area is determined.


90

Overview of Pressure Vessel Design Instructor’s Personal Notes Sample Problem 3 - Solution, cont’d • Calculate reinforcement area available in nozzle wall, A2, as smaller of A 21 or A22. A21 = (tn-trn ) 5t A22 = 2 (t n-trn ) (2.5 tn + t e)

79

Instructor’s Outline Available reinforcement area in the nozzle is determined by checking two equations.


91


Sample Problem 3 - Solution, cont’d Where: trn =

Required thickness of nozzle wall, in.

r =

Radius of nozzle, in.

te =

0 if no reinforcing pad.

te =

Reinforcing pad thickness if one installed, in.

te =

Defined in Figure UG-40 for self-reinforced nozzles, in.

80

Instructor’s Outline Review the relevant parameters.


92


Sample Problem 3 - Solution, cont’d • Calculate required nozzle thickness, t rn (Figure 4.6)

t rn

t rn

=

=

Pr SE1 − 0. 6P

300 (3. 8125 + 0. 0625) 15,000 × 1 − 0. 6 × 300

= 0. 0784

in.

81

Instructor’s Outline Calculate required thickness using the equation for a cylinder.


93


Sample Problem 3 - Solution, cont’d • Calculate A2. A21 = (tn - trn)5t = (0.5 - 0.0625 - 0.0784)

× 5 (0.5625 - 0.0625)

= 0.898 in.2 A22 = 2 (tn - t rn) (2.5 tn + t e) = 2 (0.5 - 0.0625 - 0.0784) [2.5 × (0.5 - 0625) + 0] = 0.786 in.2 Therefore, A2 = 0.786 in.2 available reinforcement in nozzle. 82

Instructor’s Outline 1. The available reinforcement in the nozzle is determined.


2. Note that in this case, the nozzle has much more excess metal available than the shell.

94


Sample Problem 3 - Solution, cont’d • Determine total available reinforcement area, A T; compare to required area. AT = A1 + A2 = 0.1 + 0.786 = 0.886 in. 2 AT < A, nozzle not adequately reinforced, reinforcement pad required. • Determine reinforcement pad diameter, Dp. A5 = A - AT A5 = (3.775 - 0.886) = 2.889 in.2 83

Instructor’s Outline 1. The nozzle is not adequately reinforced because it does not have enough reinforcement available.


2. The problem now proceeds to determine the required dimensions of a reinforcement pad. Note, however, that the additional reinforcement could also be added by using a thicker nozzle or by using a thicker shell section near the nozzle.

95


Sample Problem 3 - Solution, cont’d • Calculate Dp te = 0.5625 in. (reinforcement pad thickness) A 5 = [Dp - (d + 2 t n)] t e 2.889 = [Dp - (7.75 + 2(0.5 - 0.0625)] 0.5625 Dp = 13.761 in. • Con fi rm Dp within shell reinforcement zone, 2d 2d = 2 × 7.75 = 15.5 in. 84

Instructor’s Outline 1. The reinforcement pad thickness was assumed to be equal to the shell thickness. This is common practice.

Therefore, Dp = 13.761 in. acceptable


2. A final check is made to ensure that the reinforcement pad is within the reinforcement zone.

96

Overview of Pressure Vessel Design Instructor’s Personal Notes Flange Rating • Based on ASME B16.5 • Identifies acceptable pressure/temperature combinations • Seven classes (150, 300, 400, 600, 900, 1,500, 2,500) • Flange strength increases with class number • Material and design temperature combinations without pressure indicated not acceptable 85

Instructor’s Outline 1. ASME B16.5 provides standard flange dimensional details. 2. Flange strength is based on dimensions and material used.

Major Learning Points The flange rating establishes acceptable temperature/pressure combinations and is based on ASME B16.5

97


Material Specification List Material Groups Material Group Number

Nominal Designation Steel

Product Forms Forgings Spe c. No .

1.1

1.2

Castings

Plat es

Grade

Spe c. No .

Grade

Spec. No.

A105

--

A216

WC B

A515

A350

LF2

--

--

A516

70

C-Mn-Si

--

--

--

--

A537

Cl.1

Carbon

--

--

A216

WCC

--

--

--

--

A352

LCC

--

--

2 ½ Ni

--

--

A352

LC2

A203

B

3 ½ Ni

A350

LF3

A352

LC3

A203

E

Carbon

Grad e 70

ASME B16.5, Table 1a, Material Specification List (Excerpt)

Figure 4.17 86

Instructor’s Outline 1. Acceptable flange materials are grouped based on similarities in strength.

Major Learning Points Flange Material Group Number is based on material specification and product form.

2. The Material Group is determined based on the specified material.

98

Overview of Pressure Vessel Design Instructor’s Personal Notes Pressure - Temperature Ratings Material Group No. Classes Temp., °F -20 to 100 200 300 400 500 600 650 700 750 800 850 900 950 1000

1.1

1.2

1.3

150

300

400

150

300

400

150

300

400

285 260 230 200 170 140 125 110 95 80 65 50 35 20

740 675 655 635 600 550 535 535 505 410 270 170 105 50

990 900 875 845 800 730 715 710 670 550 355 230 140 70

290 260 230 200 170 140 125 110 95 80 65 50 35 20

750 750 730 705 665 605 590 570 505 410 270 170 105 50

1000 1000 970 940 885 805 785 755 670 550 355 230 140 70

265 250 230 200 170 140 125 110 95 80 65 50 35 20

695 655 640 620 585 534 525 520 475 390 270 170 105 50

925 875 850 825 775 710 695 690 630 520 355 230 140 70

Figure 4.18 87

Instructor’s Outline 1. This table combines information for three Material Groups for illustrative purposes.

Major Learning Points Pressure/temperature rating is a function of Material Group and design temperature.

2. Review the information in this table and how it is used to determine the appropriate flange rating.

99

Overview of Pressure Vessel Design Instructor’s Personal Notes Sample Problem 4 Determine Required Flange Rating Pressure Vessel Data: Shell and Heads:

SA-516 Gr.70

Flanges:

SA-105

Design Temperature: 700°F Design Pressure:

275 psig

88

Instructor’s Outline 1. Sample Problem 4 illustrates how to determine flange rating.

Major Learning Points Sample Problem to illustrate determining flange rating.


100

Overview of Pressure Vessel Design Instructor’s Personal Notes Sample Problem 4 - Solution • Identify flange material specification SA-105 • From Figure 4.17, determine Material Group No. Group 1.1 • From Figure 4.18 with design temperature and Material Group No. determined in Step 3 – Intersection of design temperature with Material Group No. is maximum allowable design pressure for the flange Class 89

Instructor’s Outline Review the problem solution.


101


Sample Problem 4 - Solution, cont’d – Table 2 of ASME B16.5, design information for all flange Classes – Select lowest Class whose maximum allowable design pressure ≥ required design pressure.

• At 700°F, Material Group 1.1: Lowest Class that will accommodate 275 psig is Class 300. • At 700°F, Class 300 flange of Material Group 1.1: Maximum design pressure = 535 psig. 90

Instructor’s Outline 1. Use the lowest flange class that is suitable for the design conditions. Flange cost increases as the class increases.


2. A given flange class is good for a range of temperature/pressure combinations for a particular Material Group.

102


Flange Design • Bolting requirements – During normal operation (based on design conditions) – During initial flange boltup (based on stress necessary to seat gasket and form tight seal Am

=W S

91

Instructor’s Outline 1. Division 1 Appendix 2 procedure for custom-designed flanges.

Major Learning Points ASME procedure must be used for custom-designed flanges.

2. Used if flange size not covered by ASME B16.5 or ASME B16.47. 3. Typical application is girth flange for shell-and-tube heat exchanger.

103


Flange Loads and Moment Arms Flange Ring

Gasket

h

t

A

hG

W

h T

hD

C

g1

H T G

HG

HD

B

g0 Flange Hub

Figure 4.19 92

Instructor’s Outline 1. Applied loads act at different flange locations.

Major Learning Points Various flange loads are applied on corresponding moment arms.

2. Flange moments are calculated for the operating and gasket seating cases.

104


Stresses in Flange Ring and Hub • Calculated using: – Stress factors (from ASME code) – Applied moments – Flange geometry • Calculated for: – Operating case – Gasket seating case 93

Instructor’s Outline 1. Various stresses are calculated for each case and must be kept within allowable limits. 2. Flange dimensions are adjusted as needed to meet allowable stresses (e.g., increase thickness, change hub dimensions, etc.).


Flange stresses are calculated and compared to allowable values.

•

Both operating and gasket seating cases must be checked.

3. Equipment suppliers use computer programs to “optimize” flange design to be least weight (i.e., lowest cost).

105


Flange Design and In-Service Performance Factors affecting design and performance • ASME Code m and y parameters. • Specified gasket widths. • Flange facing and nubbin width, w • Bolt size, number, spacing

94



1. Flange is designed for specific gasket type, dimensions, and facing details. Changing any of these after flange is fabricated (e.g., gasket type) can adversely affect in-service performance.

Various parameters affect flange design and performance.

2. TEMA specifies minimum gasket width and bolt spacing criteria.

106


ASME Code m and y Factors Gasket Factor, m

Min. Design Seating Stress y, psi

Flat metal, jacketed asbestos filled: Soft aluminum Soft copper or brass Iron or soft steel Monel 4-6% chrome Stainless steels and nickel-base alloys

3.25 3.50 3.75 3.50 3.75 3.75

5,500 6,500 7,600 8,000 9,000 9,000

(1a), (1b), (1c), (1d); (2); Column II

Solid flat metal: Soft aluminum Soft copper or brass Iron or soft steel Monel or 4-6% chrome Stainless steels and nickel-base alloys

4.00 4.75 5.50 6.00 6.50

8,800 13,000 18,000 21,800 26,000

(1a), (1b), (1c), (1d); (2), (3), (4), (5); Column I

Gasket Type and Material

Facing Sketch and Column in ASME Table 2-5.2 (Figure 4.21)

Figure 4.20 95



1. This is an excerpt from Table 2-5.1.

•

2. Review the variation in m and y with gasket type.

Gasket m and y factors are based on gasket type.

•

Gasket type also affects gasket width used in calculations.

107


ASME Code Gasket Widths Facing Sketch (Exaggerated)

Basic Gasket Seating Width b o

N

Column I

Column II

N 2

N 2

N

(1a) N

N

(1b) w

T N

(1c) w

w

≤N

w + T ;  w

 

2

T

+N

max  

w + T  w + N ; max  2  4 



4

N

(1d)

w ≤N H

H

G

G

G O.D.Contact Face

h

G

b

G

h

G

C Gasket L Face

Forb o >¼in.

For b o < ¼in.

ASME Code Gasket Widths (Table 2-5.2 excerpt)

Figure 4.21 96

Instructor’s Outline 1. This is an excerpt from Table 2-5.2. 2. Review the flange facings shown.

Major Learning Points The gasket width used in the calculations depends on the type of flange facing.

108


Gasket Materials and Contact Facings Gasket Materials and Contact Facings Gasket Factors m for Operating Conditions and Minimum Design Seating Stress Gasket Material

Gasket Factor

Flat metal, jacketed asbestos filled: Soft aluminum Soft copper or brass Iron or soft steel Monel 4% - 6% chrome Stainless steels and nickel-base alloys

m

Min. Design Seating Stress y , psi

3.25 3.50 3.75 3.50 3.75 3.75

5500 6500 7600 8000 9000 9000

Sket ches

y

Facing Sketch and Column in Table 2-5.2

(1a), (1b), (1c),2, (1d) 2, (2)2, Column II

Figure 4.22 97

Instructor’s Outline Review the additional gasket information shown.

Major Learning Points Information on additional gasket types.

109


Maximum Allowable Working Pressure (MAWP) Maximum permitted gauge pressure at top of vessel in operating position for designated temperature • MAWP ≥ Design Pressure • Designated Temperature = Design Temperature • Vessel MAWP based on weakest component

98

Instructor’s Outline 1. Emphasize that MAWP is based on the as-supplied component thicknesses.

– Originally based on new thickness less corrosion allowance – Later based on actual thickness less future corrosion allowance needed

Major Learning Points MAWP is defined.

2. Thicknesses used exclude corrosion allowance and thickness added to absorb other loads. 3. MAWP is useful to know for potential future rerate.

110


Local Loads • Piping system • Platforms, internals, attached equipment • Support attachment

99

Instructor’s Outline 1. Review the typical external loads that may be applied.

Major Learning Points Externally applied loads must also be considered in vessel design.

2. External loads cause local stresses that must be evaluated. 3. Other industry standards must be used to evaluate local stresses (e.g., WRC 107 and 297).

111


Types of Vessel Internals • Trays • Inlet Distributor • Anti-vortex baffle • Catalyst bed grid and support beams • Outlet collector • Flow distribution grid • Cyclone and plenum chamber system 100

Instructor’s Outline 1. Different types of internals are used to perform various process functions.

Major Learning Points Several types of vessel internals may be installed.

2. Review list of internals. 3. ASME Code does not cover design of internals. End-user, vessel vendor, and/or contractor must develop requirements.

112


ASME Code and Vessel Internals • Loads applied from internals on vessel to be considered in design • Welding to pressure parts must meet ASME Code

101

Instructor’s Outline Discuss ASME requirements for loads applied to vessel and welding to pressure parts.

Major Learning Points ASME Code requires that internals be considered only to extent of their effect on pressure shell.

113


Corrosion Allowance For Vessel Internals • Removable internals: CA = CA of shell – Costs less – Easily replaced

• Non-removable internals: CA = 2 (CA of shell) – Corrosion occurs on both sides 102

Instructor’s Outline 1. Potential corrosion of internals should not be ignored.

Major Learning Points Corrosion allowance should be considered in the design of internals.

2. Corrosion allowance should be considered in a practical and costeffective manner.

114


Head-to-Shell Transitions th

th t r a p r e n n i h T

l y

t r a p r e n n i h T

l

Tangent Line

y

t

ts

s

th

y l

th

Tangent Line

y t r a p r e n n i h T

l

t

t

s

t r a p r e n n i h T

s

Fillet Weld

Butt Weld Intermediate Head Attachment

Figure 6.1 103

Instructor’s Outline 1. Review typical acceptable welding and fabrication details.

Major Learning Points ASME Code specifies acceptable welding and fabrication details.

2. Details for openings were previously reviewed. 3. Highlight thickness taper. 4. Intermediate heads should retain fillet weld in refinery applications.

115


Typical Shell Transitions CL

In all cases, l shall not be less than 3y.

CL

y

l l

C L

Figure 6.2 104

Instructor’s Outline Review thickness taper requirements.

Major Learning Points ASME Code fabrication details.

116


Nozzle Neck Thickness Tapers

Figure 6.3 105

Instructor’s Outline Thickness taper may be required in nozzle neck.


117


Stiffener Rings

In-Line Intermittent Weld Staggered Intermittent Weld

Continuous Fillet Weld On One Side, Intermittent Weld On Other Side

Figure 6.4 106

Instructor’s Outline 1. Vacuum stiffening ring attachment details.


2, ASME Code specifies weld spacing, size, and length.

118

Overview of Pressure Vessel Design Instructor’s Personal Notes Post Weld Heat Treatment • Restores material properties • Relieves residual stresses • ASME Code PWHT requirements – Minimum temperature and hold time – Adequate stress relief – Heatup and cooldown rates

107

Instructor’s Outline 1. ASME Code specifies PWHT requirements only for relief of residual stresses.

Major Learning Points ASME Code PWHT requirements.

2. Need for PWHT due to other reasons must be specified by end-user or contractor. •

Service considerations (e.g., wet H 2S, caustic)

•

Weld hardness reduction

119

Overview of Pressure Vessel Design Instructor’s Personal Notes Inspection and Testing Inspection includes examination of:

• Base material specification and quality • Welds • Dimensional requirements • Equipment documentation 108

Instructor’s Outline Highlight main areas included in inspection.

Major Learning Points ASME Code inspection requirements.

120

Overview of Pressure Vessel Design Instructor’s Personal Notes Common Weld Defects B et we en Wel d B ead an d Ba se Me ta l

B et we en A dj ac en tP as se s

Lack of Fusion

I nc om pl et e F li li ng at Ro ot on On e S id e O nl y

I nc om pl et e F il li ng at Ro ot

Incomplete Penetration External Undercut

InternalUndercut

Undercut

Figure 7.1 109

Instructor’s Outline Review common types of weld defects.

Major Learning Points Particular types of weld defects may occur.

121

Overview of Pressure Vessel Design Instructor’s Personal Notes Weld Defects Presence of defects: • Reduces weld strength below that required • Reduces overall strength of fabrication • Increases risk of failure

110

Instructor’s Outline Review why weld defects can reduce vessel integrity.

Major Learning Points Presence of unacceptable weld defects reduces vessel integrity.

122


Types of NDE NDE TYPE Radiographic

Visual

Liquid Penetrant

Magnetic Particle

Ultrasonic

DEFECTS DETECTED Gas pockets, slag inclusions, incomplete penetration, cracks Porosity holes, slag inclusions, weld undercuts, overlapping Weld surface-type defects: cracks, seams, porosity, folds, pits, inclusions, shrinkage Cracks, porosity, lack of fusion Subsurface flaws: laminations, slag inclusions

ADVA NT AGES Produces permanent record. Detects small flaws. Most effective for butt-welded joints. Helps pinpoint areas for additional NDE.

L IM IT AT ION S Expensive. Not practical for complex shapes.

Can only detect what is clearly visible.

Used for ferrous Can only detect and nonferrous surface materials. Simple imperfections. and less expensive than RT, MT, or UT. Flaws up to ¼ in. beneath surface can be detected. Can be used for thick plates, welds, castings, forgings. May be used for welds where RT not practical.

Cannot be used on nonferrous materials. Equipment must be constantly calibrated.

Figure 7.2 111

Instructor’s Outline 1. Review NDE methods and types of defects detected. 2. Review advantages and limitations of each NDE method.


Different NDE methods are best suited to detect particular defect types.

•

Each NDE method has advantages and disadvantages.

123

Overview of Pressure Vessel Design Instructor’s Personal Notes Typical RT Setup X-Ray Tube

X-Ray

Film

Test Specimen

Figure 7.3 112

Instructor’s Outline Review typical setup for RT inspection.

Major Learning Points Typical RT setup.

124


Pulse Echo UT System Cathode Ray Tube (CRT)

A

C

Read Out

B

BaseLine Input-Output Generator

Cable

Transducer A Couplant Test Specimen

B C

Flaw

Figure 7.4 113

Instructor’s Outline Review how pulse echo UT system can detect defects.

Major Learning Points Typical pulse echo UT system.

125


Pressure Testing • Typically use water as test medium • Demonstrates structural and mechanical integrity after fabrication and inspection • Higher test pressure provides safety margin • PT = 1.5 P (Ratio)

114

Instructor’s Outline 1. Water is a safer test medium than air. Pneumatic testing should only be used on an exception basis.

Major Learning Points Pressure test is used as final demonstration of vessel integrity.

2. “Ratio” is the lowest value of:

S( test temperatur e) S ( design temperatur e)

126


Pressure Testing, cont’d Hydrotest pressures must be calculated: • For shop test. Vessel in horizontal position. • For field test. Vessel in final position with uncorroded component thicknesses. • For field test. Vessel in final position and with corroded component thicknesses. • PT ≤ Flange test pressure • Stress ≤ 0.9 (MSYS) • Field test with wind 115

Instructor’s Outline Review additional pressure test design considerations.

Major Learning Points Pressure test considerations.

127


Summary • Overview of pressure vessel mechanical design • ASME Section VIII, Division 1 • Covered – Materials

– Design

– Fabrication – Testing

– Inspection

116

Instructor’s Outline 1. Highlight the subjects covered in the course.

Major Learning Points Summarize course.

2. Note that much more time is required for an in-depth discussion of pressure vessel design. This course provides a good starting point to proceed further for those who need to. 3. Provide the evaluation form for the class to complete. Collect these and return them to the sponsoring unit. 4. Distribute the CEU form to the participants and point out that they will have to mail it in themselves, with the required standard fee. All the information is on the form.

128

Appendix A Reproducible Overheads

Appendix B Course & Instructor Evaluation Form

ASME Career Development Series Course Evaluation

Course Title: ________________________________________________ Location: ___________________________________________________ Instructor: __________________________________________________ Please assist us in the evaluation of this program. Answer the following questions by circling only one answer unless otherwise stated. We will be using your feedback to plan future programs. Your assistance is most appreciated. Please return to instructor as requested. A.

Course Evaluation

Please record your overall reaction to the program by placing a circle around the app ropriate number on the scale. 10 9 Excellent

876 Good

Fair

543 Poor

210

Please evaluate the course by circling E (excellent), G (good), F (fair), or P (poor) in the appropriate location. 1.

Course content matches brochure description

1.1 E G F P

Relevance of New course notes/ Applic ability Knowledge Overall workbook to your job Gained

1.2 E G F P

1.3 E G F P

Rating

1.4 E G F P 1.5 E G F P

2.

What do you think was the best feature of the course?

3.

What changes, if any, would you make in the program content and/or format?

4.

Can you share with us any comments about this program that we coul use as a quote on our course literature?

Optional Information:

Name: _______________________________ Company: ____________________________

Title: _______________________________ City, State: __________________________

131

B.

Instructor’s Evaluation

Please evaluate the instructor(s) by circling E (excellent), G (good), F (fair), or P (poor) in the appropriate location 5.

Effective knowledge of subject matter

1.1 E G F P

Effectiveness Effective o f te achi ng us e o f Cl ass method class time

1.2 E G F P

1.3 E G F P

Openness to Ov er al l Participation Rating

1.4 E G F P 1.5 E G F P

C. 6.

Facilities How would you rate the meeting site?

7.

How would you rate the overnight accommodations (if applicable)?

8.

I n w hat oth er citi es wou ld you lik e to see thi s cour se held ?

9.

Additional Comments:

D. 10.

Future Courses and Educational Products (Video, Self Study, Software) Wh at oth er cou rses wo uld yo u like to s ee spo nsor ed?

11.

What educational products would you like to see sponsored by ASME and in what medium?

E.

On-Site Company Training

12.

Would your organization be interested in holding this course or other ASME courses at your facility? If so, please indicate the area of interest and the contact person. Thank you.

13.

Course Name/Topic: _________________________________________________________

14.

Contact Name: ________________________________ Phone No.: ___________________

132

Appendix C

Continuing Education Unit (CEU) Submittal Form Course Improvement Form

133

ASME Career Development Series Continuing Education Unit (CEU) Request Form

Each 4-hour ASME Career Development Series Course earns 0.4 CEU’s PLEASE PRINT ALL YOUR INFORMATION CLEARLY YOUR CERTIFICATE WILL BE PREPARED FROM THIS FORM

Title of Program: ______________________________________________ _______ Date Held: __________________________________________________________ Instructor: __________________________________________________________ Location: ___________________________________________________________ Number of CEU’s Earned: (0.4 per 4-hour module) ____________ Last Name: __________________________________________ First Name, Middle Initial: ______________________________ Title/Position: ________________________________________ Company: ___________________________________________ Address: ____________________________________________ City: _______________________ State: __ Zip: ____________ Telephone: __________________ Fax: ____________________ Email: _________________________ Please send this form, along with a check made out to ASME for the standard fee of $15.00 to: ASME Continuing Education Institute Three Park Avenue New York, NY 10016-5990 Your Certificate will be prepared and sent to the address you indicated above.

134

ASME Career Development Series Course Improvement Form

Important Note: Submission of this form is optional. However, we would like to solicit the comments of the Instructor so that we may continuing improve on the Career Development Series. Any instructors who would like to write a course should indicate so on this form and an authors package will be forwarded to you. Thank you for helping us with the Career Development Series

Name: _________________________________________________________ Address: _______________________________________________________ City/State/Zip: __________________________________________________ Telephone: ______________________________ Fax: ____________________________________ Email: __________________________________ Comments:

Please send this form to: ASME Continuing Education Institute Three Park Avenue New York, NY 10016-5990

135

ASME Career Development Series Instructor’s Biography Form

Important Note: Submission of this form is required every time a Career Development Series Course is taught. ASME cannot process attendees’ CEU requests without this form. Attachments to this form must include: 1. A biographical sketch of the instructor. 2. Course evaluations filled out by the participants at the completion of the course.

Course: ____________________________________________________ Date Presented: ______________________________________________ Location: ___________________________________________________ Instructor: __________________________________________________ Number of participants: ________________________________________ Sponsoring Unit: _____________________________________________

136

Pressure Vessel Design ASME Guide

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