1

SCHOOL OF CIVIL, ENVIRONMENTAL & CHEMICAL ENGINEERING

PROC 2076 / Chemical Engineering Design

Materials Selection and Design of Oil and Gas Pipeline System

Group 20

1 May, 2023

Augustina Goh

Members :

Muhamad Syarifuddin Ab Aziz

Muhammad Shafeeq Ayub

Muhammad Syafiq Danial Dany

Mohd Afif Irfan Norazhar

Umar Faruq Zamanuri

2

Executive Summary

This project requires us to select materials for piping design. Piping is an assembly of

pipes, flanges, gasket, valves, fitting and other components used to mix, distribute, control,

transfer fluid to a specific places. The better the material for the pipe, the longer the pipe

can last. Main threat in piping is corrosion that occurs due to present of oxygen, chloride

(in sea water), carbon dioxide (wet and dry) and others. Although there is no corrosive

element in kerosene, air still presents within the pipe even a small amount. That is for the

internal surface problem. For the external surface of pipes, the problem relies on the

environment. Our team decided to build pipes underground because of its advantage over

utilidor construction. There are approximately, 45% mineral, 20-30% water, 20-30% air

and 5% organic matter in the soil making external corrosion undeniable. Some criteria such

as corrosion resistant, cost, maintenance, availability, fracture toughness and fatigue

endurance are discussed and given rank. Then, material are selected and given ranked too

based on criteria and they were Titanium, Carbon Steel, Stainless Steel, Bronze and

Hasteloy C. We found that carbon steel is the most efficient material regarding its cheap

cost. Carbon steel then can be coated with Multi-component epoxy and polyurethane

coating (internal) and powder coating (external) to protect it from corrosion. More

information regarding cost of internal coating and external coating for carbon steel vs. cost

of stainless steel pipe is needed to make an absolute choice for best material. Criteria like

joining and density also should be focused more as joining of pipes involved considerable

amount of workforces and cost.

3

Table of Contents

Executive Summary.................................................................................................2

Table of Contents.....................................................................................................3

List of Figures and Tables........................................................................................4

Introduction / Scope.................................................................................................5

Background / Literature Review..............................................................................6

Main Body of Report: Material Requirements and Selection..................................8

Pipe Coating...........................................................................................................15

Conclusions and Recommendations......................................................................16

References..............................................................................................................17

Appendix................................................................................................................19

4

List of Figures and Tables

Figure.1 - Pipeline Typical Flow Scheme (Export Crude)

Table.1 – Criteria Definition

Table.2 – Criteria Comparison

Table.3 – List of Material and Their Resistant Against Each Fluid

Table.4 – Materials and Its Rank On Each Criteria

5

Introduction / Scope

Piping is an assembly of pipes used to transfer fluid between places such as storage tank,

processing factory and other. Piping construction can be seen everywhere especially in oil

and gas industry. Food processing and transfer of gas to resident house also used pipes of

different materials. The objective of this report is to resolve the problem with chosen type

of piping and try to build new efficient pipes for transporting chosen fluid. There will be

some material that needs to be chose and how the pipe work and its principle are going to

be explained. Before choosing material, rank of criteria will be discussed and ranked

according to its definition. Material selection is the most important part because the

efficiency of one process in industry decided by the quality of the material chosen and the

selection of material will base on how well the material resists corrosion. For example,

stainless steel and carbon steel give different effect on pipes cause of its different

properties. The piping project will be conducted whether under the ground or utilidor

depends on their pros and cons, and of course their environment factor will be different.

Coating of pipes is necessary depends on the type of material and its environment.

6

Background / Literature Review

Piping is an assembly of pipes, fittings, flanges, bolting, gaskets, valves, strainers, pipe

supporting elements, expansion joints, and other components used to convey, distribute,

mix, separate, discharge, meter, control, or snub fluid flows. For example, the commonly

used types of pipeline in oil and gas industry are flow lines, injection lines, export lines,

subsea pipelines and etc. In this report, the type of pipeline used to transfer kerosene is

export lines which transfer fluid from processing facility to tankage or loading point. The

tankage or storage tank is a cylindrical, vertical, open or closed tank that has many sizes

and capacities for containing petroleum products within atmospheric pressure. The storage

tank normally has a maximum operating temperature of 260°C. The kerosene transferred to

tankage should be under flashpoint. Flashpoint is the minimum temperature for the liquid

to ignite in air by forming a mixture at the surface of the liquid. From the definition, we

can see the lower the temperature the more easily for the liquid to ignite.

Figure.1 Pipeline Typical Flow Scheme – Export Crude

The main problem with piping is the corrosion due to present of; oxygen, carbon dioxide,

chloride, H2S and others.

Kerosene is free from such corrosive elements. But, the present of air in the pipes cannot

be avoided. There will be corrosion due to Oxygen, Carbon Dioxide and erosion (abrasion,

corrosion due to the flow of the fluid and its velocity within the pipe). For external surface

of pipe, it is exposed to air even the pipe is buried under ground surface. The typical soil

consists of approximately 45% mineral, 5% organic matter, 20-30% water, and 20-30% air.

7

Airs contain oxygen and carbon dioxide which induced corrosion where CO2 corrosion

(Sweet Corrosion) result in metal loss in the process fluid. Oxygen corrosion occurs when

metal is exposed to oxygen which leads to oxidation and metal loss. Acidity in soil also

can corrode a material such as steels. The greater the acidity, the higher the rate of

corrosion.

In this report the pipe will be buried instead of utilidor construction. From our research,

buried pipe is the recommended alternative, where possible. This is because buried pipes

do not disrupt roadways and lots, not subject to ambient temperature and vandalism. The

temperature below ground surface is around 20ºC, suitable for piping where temperature

(under flashpoint) of fluid low is a desirable. The buried pipes maintenance is cheaper than

utilidor type piping. Although it is hard to conduct maintenance, the pros still outperform

the cons.

8

Main Body of Report: Material Requirements and Selection

In this section, we are going to select appropriate materials for our piping design by using

suitable criteria. But first, ranking for the criteria must be made. The ranking is according

to the environment where the pipes will be installed and depends on the type of fluid used.

After that, using the criteria along with the ranking the selected materials are ranked

corresponding to its properties. Here is the list of criteria:

Table 1 - Criteria Definition

Criteria Definition.

Cost The price of the materials and substance

used to make those pipelines.

Availability The abundances of the material since the

less abundance it is the more expensive it

will be.

Maintenance Cost of maintenance activities such as

planned repairs, inspection, replacement and

equipment change.

Fracture Toughness The ability to withstand damage and not

fractured (cracked).

Fatigue Endurance The ability to withstand a long period of

cycle of the fluid during the life of piping

system.

Corrosion Resistant Affinity of a substance (usually a metal) to

withstand the damage caused by oxidization

or other chemical reaction.

Melting Point The max temperature where a material

melts.

Thermal Conductivity The tendency of the material to conduct

9

heat.

From this point, criteria from the table above will be ranked in relation to our project.

Using properties of kerosene when transferring it to tankage, the component of soil and air,

we discussed the importance each criteria and give rank to it using comparison chart

below. The constant appearances of criteria in the table below depict its usefulness.

Table 2 - Criteria Comparison

10

From the table above, the rank is as follows:

1) Corrosion Resistant

Our main concern in this project. Even though kerosene is not corrosive, air still

present leading to corrosion and there are external corrosion too due to exposure to

air. Corrosion damaged the pipe and can halt the process of transferring fluid within

the factory. That is why a material which resists corrosion is highly desirable.

2) Cost

Every company wants to save cost when constructing a facility. The cheaper the

material the better. But, it’s not just initial cost that need to be concern about, long

term cost should be consider as well such as the cost of repair, maintenance and etc.

3) Maintenance

The material must have good properties as it would long last. Material such as

stainless steel doesn’t need a future maintenance because of it high sustainability.

The less maintenance, the less the cost of maintenance. One of the reasons why

maintenance rank below cost.

4) Fatigue Endurance

The stronger the material, the higher the fatigue endurance. When the material has

high fatigue endurance, the higher the number of cycle of the fluid the pipe can

withstand. Thus, the gap of future maintenance increases, nonetheless saving cost.

5) Availability

After considering above criteria, then we have to consider its availability. Even if

the material has outstanding performance, if it’s a rare material (not abundance

within that area or country) it would be expensive. It’s number 5 in ranking because

although the material might be expensive, a long term benefit might beat the cons.

11

6) Fracture Toughness

The maximum temperature when transferring kerosene is 38°C and below. Unseen

problem such as temperature drop might happen probably because of cold winter

although the pipe is buried. When temperature drops, pressure also drop and the

material have to withstand such changes or cracked is imminent.

Next, we selected materials from the most important aspect which is corrosion resistant.

Then we go slowly through criteria above from top 1 to number 6 and add other criteria if

necessary.

Corrosion Resistance 1) Excellent 2) Good  3) Poor

Fluid

Metal

Carbon Steel

Cast Iron

302 and 304

Stainless Steel

316 Stainless

SteelBronze Durimet Monel Hasteloy

BHasteloy

C Titanium

Carbon dioxide, dry 1 1 1 1 1 1 1 1 1 1

Carbon dioxide, wet 3 3 1 1 2 1 1 1 1 1

Oxygen 1 1 1 1 1 1 1 1 1 1

Petroleum oils 1 1 1 1 1 1 1 1 1 1

Water, sea 2 2 2 2 1 1 1 1 1 1

Calcium Chloride (alkaline) 2 2 3 2 3 1 1 1 1 1

Magnesium ions 1 1 1 1 2 1 1 1 1 1

Sulfuric acid, air free 3 3 3 3 2 1 2 1 1 2

Table 3 – Material resistant against corrosion rating

Table above shows metals with it corrosive resistant against specific type of fluid. From

the table above, we can see that titanium, nickel alloy and stainless steel have excellent

resistant against almost all of the fluid listed. The highlighted row means the fluid is

12

present as a threat in our project. Sea water containing NaCl is considered present because

of condensate seawater. Carbon and bronze has medium corrosion against the highlighted

fluid.

Next, we bring the chosen materials from table above to the next stage. The following is

the material we could discuss further.

1. Titanium

2. Stainless steel

3. Hasteloy C (Nickel Alloy)

4. Carbon Steel

5. Bronze

Unselected material is due to:

Monel: Too expensive although it is resistant to salt which is highly desirable.

302 and 304 Stainless Steel, 316 Stainless Steel : There are many types of stainless steel,

thus a general stainless steel is chosen to simplify things. While for Durimet (stainless

steel), it is hard to cut and require many workforces for cutting.

Cast Iron : Cast iron is vulnerable to rust when exposed to moisture

13

The table below shows the top 6 criteria with the chosen materials. Each material has their

advantages and disadvantages. The materials will be ranked according to the respective criteria.

The rank of criteria decreases from left to right.

Citeria Corrosion Resistant

Cost Maintenance Fatigue endurance

Availability Fracture toughness

score

Titanium 1 3 1 2 2 2 11

Stainless Steel

1 3 1 1 2 1 9

Hasteloy C(nickel)

1 3 1 1 2 2 10

Carbon Steel

3 1 2 1 1 1 9

Bronze 1 3 2 3 1 1 11

Table 4 - Materials and Its Rank on Each Criteria

From the table above, the rank is as follow:-

1. Stainless Steel and Carbon Steel

2. Hasteloy C

3. Bronze

4. Titanium

Although stainless steel and carbon steel has the same scores, carbon steel fall in our 1st

rank while carbon 2nd.

1. Carbon Steel: Among the threat, carbon steel is weak against sea water and wet

carbon dioxide where stainless steel is much better. But this problem can be solved

by coating both internal and external surfaces of carbon steel pipe. The price of

carbon steel is almost 10 times cheaper compared to stainless steel. The good

fracture toughness increases its fatigue endurance (life span) and reduces the needs

for maintenance and repairs. Carbon steel does not rot and can withstand natural

disaster such as earthquake and tornado. It is also highly resistant to vibration and

shock. What makes carbon steel interesting is it can be recycled without losing any

strength and makes it environmentally friendly.

14

2. Stainless Steel: It has good corrosion resistant against all fluid especially chlorides

which are present in sea water, but its cost make people reject this option. Stainless

steel doesn’t need to be coated like carbon steel and that fact reduce the

maintenance cost. Thus, no need for repainting and nonetheless further reducing the

cost. But, if maintenance is made, it will cost 3 times the amount to construct the

stainless pipe. Still, long term investment can be considered.

3. Hasteloy C: Hasteloy C is an excellent corrosion resistant and salt which supposed

to be a good material for piping. But, the fact it is the most expensive in the list

turns decreases its rank. If the cost for the material is expensive the maintenance

must be expensive too. Maintenance at least needs to be done 1-10 times a year for

Hasteloy pipes. Its fracture toughness is not as good as carbon steel and bronze.

4. Bronze : Copper is corrosion resistant and strong. Making it long lasting and

require less maintenance. However, the downside is that the price of copper is

expensive due to its low availability. Its fracture toughness exceeds the 5 materials

and sadly the rate of wear surpasses those 5 materials too.

5. Titanium: Also a good corrosion resistant. Once again, the high price is one of the

downside. It also has poor wear resistant. Maintenance needs to be done every 6-12

months. Its availability is still good but there’s a limit when buying it. The fracture

toughness is the lowest among the 5 materials. Higher risk of cracked. Cracking of

pipe during sudden pressure drop especially during start-up is not a trivial thing.

After ranking materials for their ability to resist corrosion and other criteria, we found out

carbon steel is the best material for piping. Cheap, strong, wear resistant and its availability

are the best fit for the pipe, but only when an internal and external coating is applied.

15

Pipe Coatings

The coating used for carbon steel pipe surface is as follow:-

Internal Coating (Multi-component epoxy and polyurethane coating)

Epoxy coating can be either double layer or thin film. Epoxy is the anti-corrosion agent. As

mention, although kerosene is free of corrosive element, oxygen and carbon dioxide (wet)

still exist within the solution. Corrosion due to oxygen and carbon dioxide still occur. The

coating limits the contact of oxygen and carbon dioxide. Kerosene might have sand in it.

These particulates become aggressively corrosive projectiles when travelling in pipes.

Such coating is able to withstand high impact created by these fast moving particulates.

External Coating (Powder Coating)

Powder coating is a passive barrier protection besides paint that physically isolating the

steel from external threat such as carbon dioxide, water, oxygen and condensate sea water)

making the carbon steel invincible to corrosion .This method is the most widely used when

protecting against corrosion. The powder coat emits zero volatile organic compounds.

Moreover, the waste powder can be collected and reused after sprayed giving it almost

96% efficiency in usage. The coating also is flexible and yields with the material it is

spread to. Thus, it is ideal when involved in transportation industry as they moved down

the road with less vibration and twisting leading to low risk of damaged material.

16

Conclusions and Recommendations

Having an appropriate design of piping nonetheless will save cost even in long-term

period. However, in order to build a better pipe, a suitable material is a must. Getting the

right material require a great knowledge on the purpose of the piping. Buried and utilidor

piping had different impact on the external surface of pipe. A comparison should be made

in future to distinguish their advantages and disadvantages. Although many recommend

buried piping, more info is needed to get the picture of how it works. The type of fluid and

any unnecessary threat within internal surface of pipe must be known too. Certain material

like carbon steel require coating while stainless steel not. More information regarding cost

of internal coating and external coating for carbon steel vs. cost of stainless steel pipe is

needed to see a bigger picture when selecting best material. Criteria like joining and

density also should be focused more as joining of pipes involved considerable amount of

workforces and cost. Same goes for density of material, the higher the density, the higher

the cost of transportation.

17

References

3 Reasons To Use Carbon Steel Pipe, Pipe, ST.Louis Pipe and Supply, viewed 10 September 2015, <http://www.stlpipesupply.com/blog/reasons-use-carbon-steel-pipe/ >

British Stainless Steel Association, 2015, Availability of Stainless Steel Grades, Viewed 16 September 2015, < http://www.bssa.org.uk/topics.php?article=684 >

CCS-Inc., 2012, Utilizing and Protecting Carbon Steel in Industrial Environments, viewed 17 September, <http://www.ccs-inc.com/ccs-resources/profile/utilizing-and-protecting-carbon-steel-in-industrial-environments>

Common Materials Used In Pipe Fittings, Pipe Fitting by Material, Pipe Fitting & Flanges B2B Market Place, viewed 5 September 2015 <http://www.thepipefittings.com/pipe-fitting-material.html#mate >

Copper Benefits For Using Copper Tubing For Mechanical Systems, Copper Development Association Inc, viewed 6 September 2015 <http://www.copper.org/applications/plumbing/benefits/#lnglstng>

Claire Soares, BH 2015,Gas Turbines: A Handbook of Air, Land and Sea Applications,2nd

edn, Wyman Street, Waltham, MA

Chef Tony Matassa, April 2105, The Advantages of Cast Iron Cookware, viewed 17 September <http://www.shopperschoice.com/content_content_1558.html>

Cathodic Protection Buried Pipeline, n.d http://onyxincorporated.com/wp-content/uploads/2012/11/Cathodic-Protection-Of-A-Buried-Pipeline-OnyxIncorporated-pipeline-inspection-services-2.png [accessed15 September 2015]

Galvanic Corrosion, Engineering Design Encyclopedia, Enggcyclopedia, viewed 15

September 2015<http://www.enggcyclopedia.com/2012/02/galvanic-corrosion/>

Japan Stainless Steel Association, MA 2012, Manual for Stainless Steel Pipes for Buildings: corrosion of stainless steel piping, Nickel Institute publishing, Brussels, Belgium, viewed 6 September 2015, <http://www.nickelinstitute.org/~/Media/Files/TechnicalLiterature/12008_PipingManualStainlessSteelPipesForBuildings.pdf>

John A.Mountford, Jr. Director Of Marketing, P 02170, ‘Titanium – Properties, Advantages And Applications Solving The Corrosion Problems In Marine Service’, Corrosion 2002, Viewed 5 September 2015, Tico Titanium Inc.

J. R. Davis, C 2010, Corrosion: Understanding the Basics, 1st edn, Material Park, OH, viewed 14 September 2015 <http://www.slideshare.net/rfmengr/corrosion-in-soils>

Jerry Weiser, N 2011, ‘Corrosion Primer: protect underground piping from corrosion and what to do before the outage, Cycle Combine Journal (CCJ), pp. 685-691

18

Jerry Weiser, Protect underground piping from corrosion: What to do before the outage https://www.nortoncorrosion.com/documents/cathodic-protection/Combined-Cycle-Outage-Handbook-2011.pdf> [accessed 15 September 2015]

Plant Pipe Coating, Technologies Equipment And Materials For Construction Repair And Rehabilitation Of Pipelines And Infrastructure, Argus Groups, Viewed 6 September 2015<http://www.arguslimited.com/pipeline_corrosion_protection/plant_pipe_coating>

Protective Epoxy Coating For Oil and Gas Pipelines, Internal And External Protective Pipeline Coatings, viewed 15 September 2015 <http://www.masterbond.com/articles/chemical-and-heat-resistance-protective-epoxy-coatings-oil-and-gas-pipelines>

Powder Coating Vs. Paint, Sparta Designing Solution, viewed 14 September 2015 <http://www.spartaengineering.com/powder-coating/>

Robert W. Serth, Thomas Lestina, MA 2014, Process Heat Transfer: Principles, Applications and Rules of Thumb, viewed 15 September 2015)

Roy Beardmore, 2010, Metal Cost, viewed 17 September, <http://www.roymech.co.uk/Useful_Tables/Matter/Costs.html>

Ray Mignogna, Corrosion in soils, http://www.slideshare.net/rfmengr/corrosion-in-soils , May 2010. (accessed 12 September 2015)

Soil composition, http://www.ctahr.hawaii.edu/mauisoil/a_comp.aspx ,2015 (accessed 12 September 2015)

19

Appendix

Appendix 1- Material and Their Pros and Cons