PIPING MATERIALS

INTRODUCTION

Piping materials are of many types. The specific material to suit a design requirement is chosen on the basis of certain key factors.

FACTORS AFFECTING SELECTION OF PIPING MATERIALS

• Mechanical properties – tensile, yield, creep, rupture, fatigue and impact

• Performance requirements and material reliability• Safety• Environmental conditions• Availability• Resistance to erosion and corrosion• Economic factors

VITAL CHARACTERISTICS REQUIRED Toughness

Creep StrengthDuctility

Good surface finishHardness

CLASSIFICATION OF PIPING MATERIALS

O T H E R S P E C IA L A L L O YS

S T A IN L E S S S T E E L

A L L O Y S T E E L

C A R B O N S T E E L

C A S T IR O N

F E R R O U S

L E A D A N D IT S A L L O YS

N IC K E L A N D IT S A L L O YS

A L U M IN IU M & IT S A L L O YS

C O P P E R & IT S A L L O YS

N O N -F E R R O U S

M E T A L L IC

C E M E N T

C E R A M IC

G L A S S

L D P E

P T F E

H D P E

P V C

N O N -M E T A L L IC

F R P P P L IN E D

M S G L A S S L IN E D

M S C E R A M IC L IN E D

M S L E A D L IN E D

M S P T F E , M S P V DF

M S R U B B E R L IN E D

L IN E D

P IP IN G M A T E R IA LS

COMMONLY USED PIPING MATERIALS LOW CARBON STEEL, LOW ALLOY STEEL AND STAINLESS STEELS

(used for high temperature services)

WROUGHT IRON, CAST IRON, DUCTILE IRON, COPPER, BRASS, ALUMINIUM AND ITS ALLOYS AND NICKEL STEEL

 OTHER PLASTICS MATERIALS

(PVC, polythene, polypropylene, asbestos cement, GR pipes, concrete, glass, rubber and some newer plastics)

TEMPERATURE LIMITATION OF PIPING MATERIALS

SI NO

MATERIAL MAX WORKING TEMP OC

REMARKS

1 Carbon Steel Yield stress decreases beyond this temp

A106 GrB 427

API 5L GrB 230

2 Alloy Steel -do-

A335 GrP11 570

A335 GrP22 600

A335 GrP91 650

3 Stainless Steel From –220 OC to 538 OC

A312 GrTP304 -200 to 500

A312 GrTP316 -200 to 538

4 Aluminium 175 Loses strength beyond this temp

5 Titanium 400 -do-

6 Thermoplastics 260 Melts beyond this temp

7 Thermosetting plastics

260 Some epoxies can be used upto 290 OC

8 Concrete 290 Cannot be used for temp intensive services

9 Rubber Room Temp -do-

MATERIAL PROPERTIESMATERIAL YIELD STRENGTH (Mpa) UTS (MPa)Carbon Steels 260-1300 500-880

Cast Irons 220-1030 400-200

Low Alloy Steel 500-1980 680-2400

Mild Steel 220 430

Stainless Steel, austenitic 286-500 760-1280

Stainless Steel, ferritic 240-400 500-800

Nickel and its alloys 200-1600 400-2000

Titanium and its alloys 180-1320 300-1400

Copper 60 400

Cooper Alloys 60-960 250-1000

Brasses and Bronzes 70-640 230-890

Aluminium 40 200

Aluminium Alloys 100-627 300-700

Lead and its alloys 11-55 14-70

Tin and its alloys 7-45 14-60

Polypropylene 19-36 33-36

Polyurethene 26-31 58

Polyethylene HD 20-30 37

Polyethylene LD 6-20 20

FERROUS MATERIALS

CARBON STEELS

Is an alloy of Iron and Carbon

Contains 0.1 % to 1.5 % of Carbon

Based on Carbon Content it can be classified into

1. Mild steel - 0.05 % - 0.30 %

2. Medium Carbon steel – 0.30 % - 0.70 %

3. High carbon Steel – 0.70 % - 1.5 %

4. It can withstand upto to a temperature of 450 C

 General chemical composition of CS is C - 0.07, 1.56 %, Mn – 1.6 %,

Si – 0.6 %, S – 0.1%, P – 0.1%.

CARBON STEEL – MATERIAL COMPOSITION

C Mn Si P SA106 GrB(1/2”-14”)

API 5L GrB(1/2”-14”)A53 GrB(1/2”-14”)

A105 (S.W.)(1/2”-1½”)

A216GrWCB2” & above

0.04 0.045CS castings suitable for high Temp services 0.3 1 0.6

0.035 0.035

Forged CS for ambient and high Temp services 0.35 0.9 0.35 0.05 0.05

MATERIAL DESCRIPTION CHEMICAL COMPOSTION

Seamless, CS pipe for low Temp services (Galv) 0.3 0.9 0.15 - 04

0.035

ERW ( E=0.85), CS pipe, Seamless 0.27 1.15 - 0.04 0.05

Seamless, CS pipe for high Temp & Pr services 0.3 0.29 - 1.06 0.1 0.035

ALLOY STEELS

• Adding of Alloying elements to improve the characteristics of the material is termed as Alloy Steel.

• Commonly used Alloying elements are Silicon, Chromium, Nickel, Molybdenum, Manganese, Vanadium, Titanium, Boron, Aluminium, Cobalt and Tungsten.

• WHAT ARE THE EFFECTS OF ALLOYING?

PURPOSE OF ALLOYING

1. Improved Corrosion resistance 2. Better Hardenability 3. Improved Machinability High or low temperature Stability Ductility Toughness 4. Better Wear resistance

INFLUENCE OF ALLOYING ELEMENTSAlloying Advantage Disadvantage

Aluminium          Resistance to heat and oxidation(2 - 5 %)          Improves scale resistance

         Imparts strength         Increases wear resistance (carbides)         Corrosion resistance         Hardness & Strength         If above 5% corrosion resistance is improved even at high temp

Manganese          Increases tensile strength & machinability         Improves hardenability

Molybdenum          High temp strength & impact resistance(0.15 – 0.6 %)          Corrosion resistance especially to chloride solutions

         MachinabilityNickel          Decreases decomposition of austenite

(upto 5%)          Increases resistance to oxidation at high temp         Decreases critical temperature         Prevents precipitaion of Cromium Carbides         Imparts strength         Wear resistance         Abrasion resistance         Increases red hardness (hot working)         Powerful deoxidiser, forms strong carbides         Wear resistance & strength         Causes fine grain structure

Increases brittleness

ChromiumMachinability,

weldability

Vanadium

Machinability

Titanium

Tungsten

LOW ALLOY STEEL – MATERIAL COMPOSITION

C Mn Si Cr Mo

0.05 - 0.15 0.3 - 0.6 0.5 1.9 - 2.6 0.87 - 1.13 HP, superheated and hot reheat Steam

0.08 - 0.12 0.3 - 0.6 0.2 - 0.5 8 - 9.5 0.85 - 1.05 Superheated steam piping system

Pipe fitting alloy steel for moderate and elevated Temp

0.05 - 0.15 0.3 - 0.6 0.5 1.9 - 2.6 0.87 - 1.13 High Temp services

Alloy steel castings for Pr containing parts suitable for high Temp services

0.18 0.4 - 0.7 0.6 2 - 2.75 0.9 - 1.2 Valves for AS pipes

Ferritic alloy steel pipe for high Temp services

DESCRIPTION CHEMICAL COMPOSTION SERVICE

STAINLESS STEEL

        Adding 11.5 % or greater chromium in iron,changes the microstructure and based on that its varieties are obtained.

        Posses greater percentage of chromium which forms a chromium oxide film exposed to air that prevents chemical attack of moist air on the material surface

        Nickel retains the austenitic structure of steel        Greater resistance to corrosion than all types of steels         Classified into three types based on its micro structure 1. Austenitic stainless steel 2. Ferritic stainless steel 3. Martensitic stainless steel

STAINLESS STEEL – MATERIAL COMPOSITION

C Mn Cr Mo Ni

A312Gr.TP316L(1/2”-14”)

A403 Gr.WP304

A351Gr.CF8A182

Gr.F304

(2” & above)

8 - 11

Forged fittings

Castings

A312 GrTP304

2-Mar 11 - 14 Corrosive process service

SERVICE

18-20 - 8 - 11Wrought austenitic stainless steel pipe fittings 0.08 2

MATERIAL DESCRIPTION CHEMICAL COMPOSTION

8 - 11 Hydrocarbons, chemicals, etc.

Welded & seamless austenitic stainless steel0.27 1.15 16-18

-

0.04 2 18-20 -

Valve castings

0.08 2 18-20 - 8 - 11 Flanges

0.08 1.5 18-21

NON-FERROUS MATERIALS

COPPER AND ITS ALLOYS

• Used when heat and electric conductivity are important• Theraml conductivity is high• Alloys are brasses, Bronzes (Cu-Sn) and Cupronickels (Cu-Ni)• Upto 20% Zn in Brass gives good corrosion resistance• Bronzes display good strength with corrsion resistance• Cupronickels have highest corrosion resistance among Cu alloys• Cupronickels are used for heat exchanger tubing

NICKEL AND ITS ALLOYS

• Easy machinability and weldability• Chloromet and Hastelloy are widely used other than Monel 400• Not resistant to oxidising environments• Monel 400 is used to handle dilute sulphuric acid and

hydrochloric acid• Alkalis and sea water do not affect Nickel

ALUMINIUM AND ITS ALLOYS

• Good thermal conductivity• Most workable metal• Highly resistant to atmospheric conditions, industrial fumes,

fresh brackish or salt water• Not resistant to corrosion• Loses strength rapidly at 1750C.

TITANIUM

• Strong and medium weight• Titanium Oxide is formed which prevents corrosion• Resistant to Nitric acid of all concentrations except fuming

nitric acid• Welding requires inert atmosphere• Loses strength above 4000C• Provides good resistance to hydrochloric acid when alloyed

with 30% Molybdenum• Not affected by impingement and crevice corrosion

COMMON NON-FERROUS PIPING MATERIALS (METALS)ASTM Des. DESCRIPTION SERVICES

SB42 Seamless Cu pipes Heat exchanger services

SB43 Seamless red brass pipes Moderate corrosion resistance

SB75 Seamless Cu tubes Heat exchanger tubing

SB161 Ni seamless pipes & tubes Alkaline solution, sea water

SB165 Ni-Cu alloy, seamless pipes & tubes Dilute sulphuric acid

SB167 Ni-Cr-Fe alloy for seamless pipes & tubes Hydro fluoric acids

SB171 Ni-Cr-Fe alloy for condenser tube plates Condenser tubing

SB210 Al alloy drawn seamless tubes Cryogenic

SB241 Al alloy extruded tubes & seamless pipes Cryogenic and low temp

SB337 Seamless and welded Ti & Ti alloy pipes Nitric acid & sea water

SB444 Ni-Cr-Mo-Columbium alloy, seamless pipes & tubes

High concentration acid

SB564 Ni alloy forgings Forged pipe fittings

SB690 Fe-Ni-Cr-Mo alloys, seamless pipes & tubes

Wear resistant services

NON-FERROUS MATERIALS COMPOSITIONASTM

DesSi Cu Al Ni

(Co)Pb Fe Zn Mn Ti P C Cr Others

SB43 - 84.6-86

- - 0.5 max

0.5 max

Rem. - - - - -

SB75 - 99.9min

- - - - - - - 0.015-0.45

- -

SB161 0.35max

0.25max

- 99 min

- 0.4 max

- 0.35 max

- - 0.15 max

-

SB165 0.52-3

0.3-0.5

0-2.4 45-72 - 6-25 - 0.5-1.5

0.05-0.1

0.02 max

0.05-

0.25

14-29

SB171 - 58-62 6-11 - 0.07-0.25

0.06-0.4

0.2-1 1-1.5 0.1-0.2

- - - Sn

SB241 0.2-0.6

0.05-0.4

- - - 0.35-0.7

0.05-0.25

0.03-1.5

0.05-0.2

- - 0.05-0.25

SB444 0.5max

- 0.4 max

58 - 5 max - 0.5 max

- 0.015 max

0.1 max

20-23

Cb, Ta, Co, Mo

SB564 0.05-1

0.2-40

0.1-0.5

20-99 - 0.2-50 - 1-3 0.1-2 0.04 max

- 0.5-35

Mo

SB690 1 max

0.75 max

- 23.5-25.5

- Rem. - 2 max

- 0.04 - 20-22

Mo, N

NON-METALLIC PIPES

COMMONLY USED NON-METALLIC PIPING MATERIALS

• Plastics – Thermoplastics and Thermosetting plastics• Concrete• Ceramic• Asbestos-Cement• Glass• Rubber

THERMOPLASTICS

POLYVINYL CHLORIDE (PVC)

• Tough and exceptionally resistant to chemical attack• Rigid unplasticized Polyvinyl Chloride is thermoplastic material• Pipes are manufactured by extrusion• Fittings, flanges and valves are manufactured by injection

moulding

TYPES OF PVC

There are three types of PVC pipes,

Type-I, “normal-impact” grade

Type-II, “high-impact” grade

Type-IV, newer grade

PVC MATERIAL PROPERTIES

PROPERTIES TYPE – I TYPE – II TYPE - IVHydrostatic design

pressure2000 psi 1000 psi 1600 psi

Temperature 160 OF - -

Grades available PVC 1120, PVC 1220

PVC, 2110, PVC 212, PVC 2116

PVC 4116

ADVANTAGES OF PVC PIPES

• No physical or little deterioration when exposed to direct sunlight, unlike other plastics

• Does not support combustion• No scales are formed over smooth inside surface

APPLICATIONS OF PVC

• Extensively used in highly corrosive application involving acids, alkalis, salt solution, alsohols and many chemical

• In oil fields as it can carry sour crude oil to which PVC is inert and paraffin built-up is minimum

• Salt-water disposal in oil fields• Gas transmission service• Cold water line in Industry as it is non-toxic and doesn’t add

any odour or taste to water• For vent piping for removal of acid fumes and corrosive gases

TETRAFLUROETHYLENE (TEFLON)

• Unaffected by alkalis and acids except flourines and chlorines, molten metals at elevated temperatures (260 0C max)

• TFE + Chlorine = CTFE, which is highly resistant to corrosion by acids and alkalis up to 180 0C

• TFE components can be prepared only by powder metallurgy

POLYETHYLENE (PE)

• Produced from hydrocarbons and ethylene under high temperature and extremely high temperature pressure

• Types – Low, Medium and High Density• HDPE is not very flexible as LDPE• 2% Carbon black is added to increase weather resistance

APPLICATIONS OF PE

• HDPE is used in jet wells and farm sprinklers• Salt water disposal lines• Chemical waste lines• Gas gathering systems• Conduit for power and telephone cables

ACRYLONITRILE-BUTADIENE-STYRENE (ABS)

• It produced by injection or compression moulding• Exhibit good toughness and tensile strength

APPLICATIONS OF PE

• Service of inorganic acids, bases and salts• Sewage piping• Crude oil and gas piping

THERMOSETTING PLASTICS

Generally produced by centrifugal casting, hand lay-up moulding and filament winding. Major resins are Epoxy and Polyester resins and generally reinforced with glass or blue asbestos fibre.

EPOXY

• Used in transportation of acids, neutral or basic salt solutions, waste process water and sewage

• Used in paper industries for pulp stock wastes and dyes• It resists fouling, salt atmosphere and marine organism• Used in food and beverage industry

CONCRETE PIPES

CONCRETE PIPING MATERIALS

• Types – reinforced and non-reinforced• Some non-reinforced concrete pipe material specifications are

ASTM C14, AASHO M86, ASTM C412, etc.• Non-reinforced pipe sizes vary from 12” to 24”• Some reinforced concrete pipe material specifications are

ASTM C76, AASHO M170, SS-P-375, etc.• Used for sewage and industrial waste, storm waste, culverts,

water supply

ASBESTOS-CEMENT PIPES

• Not used very commonly• Some standard material specification are ASTM C296, AWWA

C400, SS-P-331, etc.• Used for drains and industrial waste

PIPE LININGS

COMMONLY USED LINING MATERIALS

• Rubber• Plastic• Lead• Glass• Epoxy resin• Synthetic resin

RUBBER LINED PIPES

• Natural and Synthetic rubber linings are used to counteract corrosion

• Generally used in the temperature range of –20 OC to 50 OC• Commonly used natural rubbers are soft rubber, semi-hard and

hard rubbers• Commonly used synthetic rubbers are Polychloroprene-

Neoprene, Butyl rubber, Nitrile rubber and Thiokol• Cannot be used for strongly oxidising conditions or halogenated

carbon

PLASTIC LINING

• PTFE and PVC are important lining materials• Used for chemical resistance, corrosion protection, resist

abrasion, non-toxic and smooth bore reduces friction• PTFE is chemically inert and used from –270 OC to 260 OC• Polyvinyl flouride, fluoroethylene propylene and polypropylene

can be added to enhance the range of PTFE• PVC provides tough and heavy-duty finish resistant to most acid

and marine growth

LEAD LININGS

• Lead lining is useful for most corrosive fluids and sulphuric acid below 80% concentration

• Should not be used for nitric acid, hydrochloric acids, hydrofluoric acids, organic acids and alkalis

• Can be alloyed to improve mechanical properties

GLASS LININGS

• Glass enamel (glass like) inorganic compositions are used as linings

• Bonded to mild steel by fusion on metal surface above 750 OC• Provide good resistance against acid attack and abrasion• Cheap alternative in many situations• Temperature range of –20 OC to 250 OC

EPOXY RESIN LININGS

• Good resistance to alkalis and most acids except strongly oxidising ones

• Good resistance to abrasion by suspended particles due to glossy nature of lining

• Used mostly in natural gas pipe lines

SYNTHETIC RESIN LININGS

• Sprayed phenol formaldehyde can be used when expected corrosion is less

• Cannot be used above 80 OC• Because of sterile and non-tainting properties it is used in food

processing industries• Mostly used to line welded steel vessels

LINED PIPES SAMPLES

PIPING MATERIAL SPECIFICATION

What is a Material Specification?

A Piping Material Specification is an engineering specification that contains requirements for the selection of materials to be used in the construction and fabrication for all process and utility piping.

FEATURES OF A MATERIAL SPECIFICATION

• Material of construction, end construction, end connections and wall thicknesses for various ranges

• Individual line class of the piping materials• Codes and standards relevant to the pipes and fittings of the

specified material class• Line class coding system• Pressure-Temperature ratings for various fittings and limiting

sizes of fittings• Other general notes and design criteria as applicable to the

material class

CLASS SERVICE INDEX – IDEA STANDARDSSI NO CLASS MATERIAL MAX P

(kg/cm2)T RANGE

(OC)SERVICE

1 A1A CS 20 -29 to 300 Fuel oil, nitrogen liquid, fuel gas, NaOH, brine, steam tracing

2 A1AR CS 20 -29 to 300 Steam condensate, BFW

3 A1B CS 20 -45 to 400 Hydrocarbons, catalyst solutions, lube oil, flare, flue gas, caustic, hot

nitrogen

4 A21A 304 SS 19.33 -29 to 300 Pure water(pump seal cooling) WPF, additive solutions, seal oil, antifoam,

carbonate, brine II

5 A21B SS 19.33 -29 to 150 Demin. Water, other process

6 A37A Aluminium 1.4 100 Pneumatic conveying

7 B1C CS - - Chlorine vapour, chlorine liquid

8 B1EH CS 52 -29 to 260 Hydrocarbons for HDPE only (Dupont B1E)

9 D21A 304 SS 101.25 -200 Liquid ethylene (Cryogenic)

10 S5A CS polypropylene

lined

10.55 -29 to 80 Chemical sewer, regeneration wastes (H2SO4 and NaOH)

SOME MATERIAL COMPARISONS

GENERAL DESIGN CONSIDERATIONS

• Seamless pipes are mostly preferred in power piping, butt welded may also be used

• API 5L pipes are not permitted by IBR for design pr.>20 kgcm2 and temp>260 OC

• Most projects require multinational specification

• Economy precedes the choice of code for material specification, after design requirements

THANK YOU

FOR YOUR PATIENCE