17_seventeenth report_shear pin_30 sept - 04 oct_rev_0

8/13/2019 17_Seventeenth Report_Shear Pin_30 Sept - 04 Oct_rev_0

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2006/030041/07

PO Box 4864Vanderbijlpark

Republic of South Africa

Tel +27(0)16 981 0237Fax+27(0)16 981 0238

Cell+27(0)82 413 0555

[email protected]

WEEKLY REPORT 09 SEPT - 13 SEPT

Name: Gustav Oehley

Student Number: 211111309

Email: [email protected]

Date: 16/09/2013

Mentor: Mr. S.E.F. Botha

Managing Director:

Supervising Foreman:

Mr. J. Greyling

Anton van Vollenstee


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Table of contents P

Cover page 1

Table of contents 2 -3

List of Figures 3

List of Tables 3

1. Abstract and Introduction 4

2. Objective 4

3. Vertical Tank Design 4

3.1 Joints 5

3.1.1 Welding Symbols 53.1.2 Vertical Shell Joints 5

3.1.3 Horizontal Shell Joints 5

3.1.4 LapWelded Bottom Joints 5

3.1.5 Butt-Welded Bottom Joints 5

3.1.6 Bottom Annular-plate Joints 5

3.1.7 Shells-to-Bottom Fillet Welds 6

3.1.8 Wind Girder Joints 6

3.2 Design Considerations 6

3.2.1 Design Factors 6

3.2.2 External Loads 6

3.2.3 Protective Measures 6

3.2.4 External Pressure 6

3.2.5 Tank Capacity 7

3.3 Design Considerations 7

3.3.1 Foundation 7

3.3.2 Corrosion Allowances 7


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3.3.3 Service Conditions 7

3.3.4 Weld Hardness 7

3.4 Bottom Plates 8

3.5 Annular Bottom Plates 8

3.6 Shell design 9

3.6.1 Allowable Stress 9

3.6.2 Calculations of thickness for Shell 11

3.7 Shell openings 11

4. Conclusion 12

5. References and Resources 12

List of FiguresFigure 1: Vertical Tank 4

List of Tables

Table 1: Shell Plate thickness with Sizes weld 5

Table 2: Plate Thickness with Hydrostatic Stress 8

Table 3: Tank diameter with Plate thickness 8

Table 4: Plate material with Allowable Stresses 10


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1. Abstract and Introduction

During this week at Onsite services, I looked into tanks and how to design them, also the calculation

involving Tanks. During previous weeks at On-site services I assisted the boilermaker with thefabrication of a 6m diameter tank and was involved in Boiler making, fittings and all the various

fabricating techniques used to erect this tank. The main engineer gave me the American Petroleum

Institute standard and through standard I was guided on tank design.

2. Objective

The objective for this report is to give feedback on the topic and time that I spend during the week and

also giving information about the content that I have researched.

3. Shear Pin Design

Figure 1: Shear Pin

A shear pin is a safety device designed toshear in the case of a mechanical overload, preventing other,more expensive parts from being damaged. As a mechanicalsacrificial part,it is analogous to

anelectric fuse.

The pin itself may be a plainmetal rod inserted through a hub and axle; the diameter of the rod iscarefully chosen to allow theshearing action when the desired breakawayforce orshock is reached.

Acotter pin may also be used as a low-tech shear pin.

They are most commonly used indrive trains,such as asnow blower'sauger or thepropellers attached

to marine engines.

Another use is inpushbackbars used for largeaircraft.In this device, shear pins are frequently used to

connect the "head" of the towbar

the portion that attaches to the aircraft

to the main shaft of thetowbar. In this way, the failure of the shear pin will physically separate the aircraft and the tractor. Thedesign may be such that the shear pin will have several different causes of failuretowbar rotation

about its long axis, sudden braking or acceleration, excessive steering force, etc. all of which could

otherwise be extremely damaging to the aircraft.
http://en.wikipedia.org/wiki/Shearing_(physics)http://en.wikipedia.org/wiki/Sacrificial_parthttp://en.wikipedia.org/wiki/Electric_fusehttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Shearing_(physics)http://en.wikipedia.org/wiki/Forcehttp://en.wikipedia.org/wiki/Shock_(mechanics)http://en.wikipedia.org/wiki/Cotter_pinhttp://en.wikipedia.org/wiki/Powertrainhttp://en.wikipedia.org/wiki/Snow_blowerhttp://en.wikipedia.org/wiki/Augerhttp://en.wikipedia.org/wiki/Propellerhttp://en.wikipedia.org/wiki/Pushbackhttp://en.wikipedia.org/wiki/Aircrafthttp://en.wikipedia.org/wiki/Aircrafthttp://en.wikipedia.org/wiki/Pushbackhttp://en.wikipedia.org/wiki/Propellerhttp://en.wikipedia.org/wiki/Augerhttp://en.wikipedia.org/wiki/Snow_blowerhttp://en.wikipedia.org/wiki/Powertrainhttp://en.wikipedia.org/wiki/Cotter_pinhttp://en.wikipedia.org/wiki/Shock_(mechanics)http://en.wikipedia.org/wiki/Forcehttp://en.wikipedia.org/wiki/Shearing_(physics)http://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Electric_fusehttp://en.wikipedia.org/wiki/Sacrificial_parthttp://en.wikipedia.org/wiki/Shearing_(physics)


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There are various types of pins as seen in figure below. Pins are normally driven into place and have

the advantage that they can transmit torque as well as axial load. The diameter of the pin is

approximately one quarter of the shaft diameter. Pins should not project beyond the hub surface for

safety reasons.

Figure 1: Types of Shear Pin

Shear pins are used as mechanical fuses. The pins are designed to transmit a certain mean torque, but if

the torque exceeds a predetermined maximum value, the pin will fail, preventing further damage to the

equipment.

3.1 StandardsThe following gives a list of standards applicable to the various types of pins:

1. Round pins BS 1804 : part 219682. Taper pins with drilling specifications ANSI B18.8.2 19783. Grooved PinsANSI B18.8.219784. Split tubular spring pins ANSI B18.8.21978


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3.2 Information Gathered


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3.3 Design StatementDesign a shear pin made out of two materials: 080M40 (EN 8) and Copper, the grade of copper must

be a design decision. The hub of the coupling must be connected with a round pin. The shaft is driven

by an electric motor and transmit 7,5 kW at 1500rpm before gearbox is engaged. The gear ratio is

100:1. The pin is allocated 141 mm for the center of the shaft.

3.4 Calculations


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3.5 ProgrammingAfter I have done the calculations on the shear pin, I wrote a excel program where I could input

different values of the design and the program would output the size of shear pin required for the

application.

Excel Program


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3.5 CAD Model


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4. Conclusion

After finishing this report and getting information on Tank design, reading and studying the standards I

can say that I have gained a large amount of knowledge in the design process of tanks. I receivedvalues of a tank to calculate the Shell thickness and base plate thicknesses. Using the API 650 standard

as a guide, I correctly calculated the correct thicknesses.

5. References and Resources

http://www.vopak.com/business_segments/storage/142_tank_terminal.php

http://www.piping-designer.com/API_650_Tank_Calculation

http://www.eng-tips.com/viewthread

Code of Federal Regulations40 CFR 280.31 Operation and maintenance of corrosion protection.

Holm L. (2012).Long Term Experiences with Solar District Heating in Denmark.Presentation.European Sustainable Energy Week, Brussels. 18 - 22 June 2012.

ASME RTP-1-2005 Part 1-110 (Scope of Standard)

"Industrial Tank Cleaning Mixer".Waterline Tank Technologies LLC.

"1910.110(e)(4)(i)".United States Department of Labor - OSHA.
http://www.vopak.com/business_segments/storage/142_tank_terminal.phphttp://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=3113bdbd55bf563c9663729770e6a78e&rgn=div8&view=text&node=40:26.0.1.1.10.3.47.2&idno=40http://www.euroheat.org/Admin/Public/DWSDownload.aspx?File=%2fFiles%2fFiler%2fPresentations%2f20120618-22_EUSEW%2f120619_EUSEW_3+-+Holm+brussel+juni+2012.pdfhttp://www.waterlinellc.com/https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=19164https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=19164http://www.waterlinellc.com/http://www.euroheat.org/Admin/Public/DWSDownload.aspx?File=%2fFiles%2fFiler%2fPresentations%2f20120618-22_EUSEW%2f120619_EUSEW_3+-+Holm+brussel+juni+2012.pdfhttp://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=3113bdbd55bf563c9663729770e6a78e&rgn=div8&view=text&node=40:26.0.1.1.10.3.47.2&idno=40http://www.vopak.com/business_segments/storage/142_tank_terminal.php

17_seventeenth report_shear pin_30 sept - 04 oct_rev_0

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