rerate specification date - site sample.pdf · client: acme chemical date 5/09/2012 report no.:...

Client: ACME Chemical

Date 5/09/2012

Report No.: 20090.039 Vessel: ACAX 80005

Contact: John Smith Phone No.: 555-836-2223 Year Built: 1970

Rerate Specification

EXECUTIVE SUMMARY

The Delaware Plant Reliability Engineer at ACME Chemicals in Claymont, DE requested Eagle Inspection Technologies to include rerate calculations with the inspection report to support the proposed rerate for the DOT Railcar ACAX 80005 to be set on stationary supports and continue in service as a stationary pressure vessel in Fluosulfonic Acid service. This request was due to the requirements of the PA Dept. of Labor and Industry for pressure vessels operating within their jurisdiction. The calculations contained herein were based on the client request to rerate the vessel to 25psig at 200ºF. A corrosion allowance was established to meet MDMT requirements without impact testing and to extend the life of the vessel for greater than 20 years at the present estimated corrosion rate. All conditions appear to be satisfactory for the proposed rerate of the Railcar ACAX 80005. Rerate must be performed in accordance with the latest revision of the National Board (NB) by a contractor that is a NB certified R stamp holder for repairs of pressure vessels. A rerate nameplate must be install on the vessel and the PSV must be reset to 25psi maximum for over pressure protection of the vessel.

MAWP No Reference MAWP 25psi

Temp No Reference Temp 200'F

MDMT No Reference MDMT -20'F

Ca No Reference Ca 0.375"

Hydro Test Orig 400psi Hydro Test 33psi

Rerate change from original design

Rerate change from original design

Evaluation i.a.w. ASME S8 D1, UCS 66 confirms MDMT at -20ºF

Established to base remaining life to >20 years, 3/8" for all components

Hydro test required due to change from critical service (class 5 corrosive medium)

StatusOriginal Design Parameters

Appendix A Vessel Rerate Engineering Calculations

Appendix B Drawings

Appendix C Supplemental Supporting Documents

Appendix D Manufacturers Data Sheets

Current Design Parameters

of 9Project No.: 20090.039 Author: Jeff Walling

Page 1

1) Cylindrical Shell Calculations

2) Formed Head Calculations

3) Nozzle Calculations

4) Nozzle Reinforcement Calculations

5) Horizontal Vessel Stress Calculations

6) Component MDMT Evaluation

7) Component Stress Calculations

Appendix A

Vessel Rerate Engineering Calculations

of 49Project No.: 20090.039 Author: Jeff Walling

Page 2


Date5/9/2012

PRESSURE VESSEL CYLINDRICAL SHELL CALCULATIONS

Project No.: 20090.039

ASME SECTION VIII, Div 1, UG-27_28

Inside Radius, in. 59.643

Design Pressure, psi33

Joint Efficiency0.70

Int. Pressure Min. Thickness Calcs

Minimum Thickness, in. 0.121

Outside Diameter, in.

Minimum Thickness, in.

External Pressure Minimum Thickness CalculationEffective Length, in. A

L/Do

Do/t

Thickness, in.0.357 Internal Pressure, psi96.4

Cu Ft3104

Cylinder Capacities

Plate Data

Sq In

178694

Gals23217

lb's ofWater 193562

ProdS.G.1.84

Sq Ft

1242

lb's of Prod.

356155

lb's of Steel

37061

MetalCu in

130804

Prod + Steel

393215

Shell Length, in. 474.000

Shell Thickness, in0.732

Variables for Capacities

Total lb's

Shell Radius, in60.000

Component Main Shell

R

P

E

S

t

L

tx

Do

Internal Pressure Calculation

Pt = tnom - Ca =

Material AAR-TC128-B

Factor from Figure G

Thickness, in.

External Pressure CalculationA

L/Do

Do/t

t Factor from Figure G

Vessel ACAX 80005

X-Chart

X-Chart

MAWP25

Temp.200

tnom0.732

Ca0.375

S.H.9.88

Do120.000

Prod. SG1.84

t for Reinf. Calc0.085

PR/(SE-0.6P) = t (> tx or PR/(S-0.6P) = tr)

tr

External Pressure, psiPa

B Stress Value

External PressurePa

B Stress Value

23100

Year Built

1970

Stress, psi

SEt/(R+0.6t) = P

Page 1 of 1Project No.: 20090.039 Author: JLW


Date5/9/2012

PRESSURE VESSEL ELLIPSOIDAL HEAD CALCULATIONS

Project No.: 20090.039 MAWP 25ASME SECTION VIII, Div 1, UG-32_33

Inside Diameter, in. 118.438

Design Pressure, psi32.9

Design Temperature,°F200

Joint Efficiency0.85

Int. Press. Min. t Calcs

Min. Thickness, in. (Knl) 0.099


External Pressure Minimum Thickness CalculationA


Component Head 1&2

D

P

T

E

S

t

t

Internal Pressure Calculation

Pt = tnom -Ca =

Material AAR-TC128-B


Thickness, in.

External Pressure CalculationAt Factor from Figure G

Vessel ACAX80005

X-Chart

Nominal Thickness, in. 0.781tnom

Inside Head Height, in. 29.610h

factor(s) (D/2H)K_K1

(Knl) PD/(2SE-0.2P) = t & (Cntrl) P0.9D/(2S-0.2P)=t (2:1 Ellipsoidal)

Ro

KoDo Ho Do/2Ho

2SEt/(D+0.2t) = P

Ro

131

Head Capacities Plate Data

Sq In18009

Gals979

lb's ofWater 8163

ProdS.G.1.84

Sq Ft125

lb's of Prod.15020

lb's of Steel3985

MetalCu in 14065

Prod + Steel

19005hm 30.000

t 0.781Variables for Capacities Total lb's

Rm 59.610

Pel 296.5

Nominal thickness, in.

Mean Head Height, in.

Mean Radius, in.

Head Perimeter, in.

(Includes 2 inch head skirt width)

Cu Ft

Ca 0.375

S.H. 9.88 Static Head, ft 0.076t Min. Thickness, in. (Cntrl)

94.750 Central Portion, in.CP

23100

B/(Ro/t) = Pa

Stress Value

External Pressure, psi

B/(Ro/t) = Pa

External Pressure, psi.

Pa

B

Stress Value

Pa

B

Stress, psi

X-Chart

Page 1 of 1Project No.: 20090.039 Author.: JLW

Client:ACME Chemical

Date 5/9/2012PRESSURE VESSEL NOZZLE CALCULATIONS

Project No.: 20090.039 Vessel ACAX 80005Year Built

1970ASME S8 D1, UG-27_45

Inside Radius, in. 9.875

Design Pressure, psi25.0

Joint Efficeincy1.00

Stress, psi20000

Int. Pressure Min. Thickness Calc

Calculated t, in. 0.063

Outside Diameter, in.


External Pressure Minimum Thickness CalculationEffective Length, in. A

L/Do

Do/t


Cu Ft1

Cylinder Capacities

Plate DataSq In

186

Gals4

lb's ofWater

33

ProdS.G.1.84

Sq Ft

1

lb's of Prod.

61

lb's of Steel237

MetalCu in 838

Prod + Steel

298

Shell Length, in. 3.000

Shell Thickness, in4.500

Variables for Capacities

Total lb's

Shell Radius, in.9.875

Comp. Manway

R

P

E

S

t

L

t

Do

External Pressure, psi

Internal Pressure Calculation SEt/(R+0.6t) = P

Pt = tnom - Ca =

Material CS - A105


Thickness, in.

External Pressure CalculationA

L/Do

Do/t

t

External Pressure


X-Chart

X-Chart

MAWP25

Temp.200

tnom4.500

Ca0.375

S.H.0.0

Do28

Prod. SG1.84

PR/(SE-0.6P) = t

5

Noz. Type Boss Flange

04

Size28

0.085Minimum Required Thickness =0.085Attaching Component tmin =

Standard Pipe - 12.5% = 0.328Minimum Design t = 0.460

Pa

B Stress Value

Pa

B Stress Value

NOTE:Flange Weight Not Considered

Page 1 of 1Project No.: 20090.039 Author: JLW

Client: ACME Chemical Date

5/9/2012

PRESSURE VESSEL NOZZLE REINFORCEMENT CALCULATIONS

Project No.: 20090.039Vessel ACAX 80005 Pressure 25 Temperature 200psi ºF

ASME S8, D1 UG-37

Component

Manway

Do28.000

t nom0.732

tn nom4.500

d19.750

E1.00

Rn9.875 2000023100

Fr10.87

Fr2 0.87

F1

Cv0.375

t0.357

tr0.357

tn4.125

trn0.085

t10.500

t20.250

h0.250

ti4.125

Vessel Material Nozzle Material

CS - A105 AAR-TC128-Btr based on:

Internal Pressures

Sv Sn

A 7.446

A1a 0.000

A2a 6.244

A3a 6.375

A41 0.216A43 0.054

Total Area Available, in.^2 8.300

A1b 0.000

A2b 72.143

A1 0.000

A2 6.244

A3b 73.661A3c 1.786

A3 1.786

Sufficient Reinforcement

Area Required

Area available in shell, in.^2 (use larger value)

Area avail. in nozzle projecting outward, in.^2 (use smaller value)

Area available in inward nozzle, in.^2 (use smaller value)

Area available in outward weld, in.^2

Area available in inward weld, in.^2

= (A1 + A2 + A3 + A41 + A43)

Nozzle Without Reinforcing Element

= dtrF + 2tntrF(1 - fr1)

= d(Et - Ftr) - 2tn(Et - Ftr)(1 - fr1)

= 2(t + tn)(Et - Ftr) - 2tn(Et - Ftr)(1 - fr1)

= 5(tn - trn)fr2t

= 5(tn - trn)fr2tn

= 5titifr2

= 2htifr2

= 5ttifr2

= t12fr2

= t22fr2

Confg. 3

1=Butt, 2=thru,3 = Ext.

Nozzle Groove Weld?

YesElement Groove Weld?

No

Cn0.375

t = 0.357

t = 0.750


Dp37.000

te0.750 13800

Fr40.597

t30.500

Fr30.597

A 7.446A1 0.000

A2a 6.244 A2c 77.390A2 6.244

A3 1.786

t10.500

A41 0.149within limits, take full credit

A43 0.054A5 4.032

Area Available, in.^212.415

Reinforcement Limit, in. = 39.5

Area Required, in.^2

A42 0.149

Pad Material:

Sufficient Reinforcement

SpCS Unknown

Nozzle With Reinforcing Element

Area available in outward weld, in.^2

Area available in inward weld, in.^2

Area outer element weld, in.^2

Area available in element, in.^2

Area available in shell, in.^2

Area avail. in nozzle projecting outward, in.^2 (use smaller value)

Area available in inward nozzle, in.^2

= A1 + A2 + A3 + A41 + A42 + A43 + A5

A1a 0.000A1b 0.000

= d(Et - Ftr) - 2tn(Et - Ftr)(1 - fr1)

= 2(t + tn)(Et - Ftr) - 2tn(Et - Ftr)(1 - fr1)

= dtrF + 2tntrF(1 - fr1)

= 5(tn - trn)fr2t = 5(tn - trn)fr2t(2.5tn + te)fr2

(use larger value)

A3a 6.375 A3b 73.661 A3c 1.786= 5titifr2 = 2htifr2= 5ttifr2

= (leg)²fr3

= (leg)²fr4

= (leg)²fr2

= (Dp - d - 2tn)te fr4

(use smaller value)


WELD LOADS AND STRENGTH PATHS

Unit Stress per UG--45 (c) and UW-15

Nozzle wall in Shear, = 0.70 x S = Snw14000Outter Noz fillet (41) in Shear, = 0.49 x S Sof6762Elem Grv Weld tension, = 0.74 x S = Tegw0Noz Grv Weld tension, = 0.74 x S = Tngw14800Repad fillet (42) in Shear, = 0.49 x S = Srf6762Inner Noz fillet (43) in Shear, = 0.49 x S Sif9800

Strength of connection elements

Nozzle wall in Shear, = Pi/2 x dm x tn x Snw STnw2164687Outter Noz fillet in Shear, = Pi/2 x Do x WL41 x Sof STof148629Elem Grv Weld tension, = Pi/2 x Do x WLte x Tgw STegw0Noz Grv Weld tension, = Pi/2 x Do x WLt x Tgw = STngw232267Repad fillet in Shear, = Pi/2 x Dp x WL42 x Srf = STrf196402Inner Noz fillet in Shear, = Pi/2 x Do x WL43 x Sif STif215404Loads to be carried by welds, per UG-41 (b) (1) and Fig. UG-41.1 sketch (a)

Limits172003[A-A1+2tnfr1(E1t-Ftr)]SvW =

244278[A2+A5+A41+A42]SvW1-1 = 172002.6

249083[A2+A3+A41+A43+2tntfr1]SvW2-2 = 172002.6

345683[A2+A3+A41+A43+2tntfr1]SvW3-3 = 172002.6

STrf + STnwPath 1-1

Strength Path Check Ratio Used/Avail.

STof + STegw + STngw + STifPath 2-2

STrf + STgw + STifPath 3-3

Repad S/Repad Weld S Ratio =Weld Load/Strength Max Ratio =

2E+06 Sat 0.07

596300 Sat 0.29

644073 Sat 0.27

0.28 OK0.29 OK


(Based on Zick Formula for Two Saddle Tanks)HORIZONTAL TANK EVALUATION

File No4

Report No20090.039

InitialsJLW

ClientACME

Tank NoACAX 80005

Date 5/9/2012

Temp. °F200

0.2833wt

ServiceFluosulfonic Acid

SG1.84

Material Catagory

CS/Crom. Stl(PCI)

FH (in.)106.60

A

21.5E

0.70S

23100

H

30.000L

474P

25D

120.000Temp.

200

ts

0.357th

0.406Y

50000

R

60.000

a°

122

28500000

Mtl # in L limit

37057CuFt in Head

130.9Mtl # in Head

4000

Total #

375209

Prod # in L limit

316290Q

187604b

12.000

tn Head

0.781tn Shell

0.732Other Weight, lbs

500

K13.14

K83.14 AAR-TC128-B

MEMaterial

Stress in Saddle (SS+) -3Stress in Mid Span (SM+) 4201

Stress due to Int Press (SP +) 2101

=([Q]*[A]*(1-((1-([A]/[L])+(([R]^2-[H]^2)/(2*[A]*[L])))/(1+((4*[H])/(3*[L]))))))/([K1]*[R]^2*[ts])

=(([Q]*[L]/4)*((1+(2*(([R]^2-[H]^2)/[L]^2)))/(1+(4*[H])/(3*[L]))-((4*[A])/[L])))/(3.1416*[R]^2*[ts])

=[P]*[R]/2*[ts]

Sum of Tensional Stress (S1 +): 63010.39 Vessel Strength is adequate for Tension LoadsRatio ([S1+]/S*E)

LONGITUDINAL BENDING STRESS

Allowable Compressive Stress 1: NA =([ME]/29)*(([ts]/[R])*(2-((2/3)*100*([ts]/[R]))))

0.006 Compression Stress not a FactorRatio = [ts]/[R] > 0.005

Allowable Compressive Stress 2: NA =[Y]/2

NA

STRESS IN TENSION

STRESS IN COMPRESSION

Stress in Saddle (SS - ) NAStress in Mid Span (SM - ) NA

=([Q]*[A]*(1-((1-([A]/[L])+(([R]^2-[H]^2)/(2*[A]*[L])))/(1+((4*[H])/(3*[L]))))))/([K8]*[R]^2*[ts])

=(([Q]*[L]/4)*((1+(2*(([R]^2-[H]^2)/[L]^2)))/(1+(4*[H])/(3*[L]))-((4*[A])/[L])))/(3.1416*[R]^2*[ts])

Sum of Compress. Stress (S1 - ): NA

=SP+SM

=SP-SM

16170Max Allow.

NAMax Allow.

NARatio ([S1-]/Mx Alw)

23100 28500000 120

Head Type

Ellipsoidal

Stiffening Rings? No


File No4

Report No20090.039

InitialsJLW

ClientACME

Tank NoACAX 80005

Date 5/9/2012

Temp. °F200

0.2833wt


SG1.84

Material Catagory

CS/Crom. Stl(PCI)

FH (in.)106.60

Stress in Shell (SS) 3087

Stress in Head (SH) 6515

Stress due to Int Press (SP). 1847

([K4]*[Q])/([R]*[th])

=[P]*[R]/2*[th]

Sum of Stress in Head: (SH3) 2346 =([K5]*[Q]/[R]*[th])+[SP]

0.28 Vessel Strength is adequate for tangential shear stress (<0.80*S)Ratio

TANGENTIAL SHEAR STRESS

0.846

Stiffening ring at horn of saddle?

K4

([k4]*[Q])/([R]*[ts])

0.393K5

0.10Ratio Vessel Strength is adequate for stresses in head (<1.25*S)

0.5WPt

6WPLWear Plate?

0.86ts

1) Contact points for the horn of the saddle determined from field measured distance of saddle contact along vessel circumference = 128 inches, and the measured circumference at 376.916 inches. Ratio = 128/376.916 = 0.339, contact angle = aº = Ratio x 360 = 122º2) ts & th based on tnom - Ca, ts = 0.732-0.375 = 0.357, th = 0.781-0.375 = 0.4063) Variables used herein were based on actual field measurements where accessible.

YesNo

Stress in Horn of Saddle (S4) -11873

Stress at Wear Plt Edge (S4) -29885

=-([K7]*[Q])/([ts]*([b]+1.56*([R]*[ts])^0.5))

0.51 Vessel strength is adequate for stress at the saddle horn (<1.50*S)Ratio

CIRCUMFERENTIAL STRESS

0.013

= -([Q]/(4*[ts]*([b]+1.56*([R]*[ts])^0.5)))-((12*[K6]*[Q]*[R])/([L]*[ts2]))

0.753

1.29Ratio Vessel strength is adequate for stress at wear plt edge (<1.50*S)

15WPw0.86

tsK6 K7

Stress in Bottom of Shell (S5) -20588

133a°

0.010K6

Wear Plate Values

0.41Ratio Vessel strength is adequate for stress in shell bottom (<.50*Y)

= -([Q]/(4*[ts]*([b]+1.56*([R]*[ts])^0.5)))-((12*[K6]*[Q]*[R])/([L]*[ts]^2))

NOTES:

Tangential Shear Stress (S2) 6515

0.377ts2

[WPt]^2+[ts]^2

Stiffening Ring(s) No


File No4

Report No20090.039

InitialsJLW

ClientACME

Tank NoACAX 80005

Date 5/9/2012

Temp. °F200

0.2833wt


SG1.84

Material Catagory

CS/Crom. Stl(PCI)

FH (in.)106.60

Variable = DefinitionA = distance from tangent line of the head to center of saddle, in.a° = horn of saddle contact angle, degreesb = width of saddle, in.D = outside diameter of vessel, in.E = joint efficiencyFH = fill height, in.H = outside depth of dish of head, in.K = constant from tableL = length of vessel tan-tan, in.M = materialME = modulus if elasticity, psiP = vessel maximum allowable working pressure, psiPCI = pounds per cu. in.PSI = pounds per sq. in.Q = load on one saddleR = outside radius of component, in.S = allowable stress value, psiSG = specific gravityth = actual thickness of head, in.tn = nominal thickness, in.ts = actual thickness of shell, in.Wpa° = wear plate contact angle, degreesWPL = wear plate length beyond horn of saddle, in.WPt = wear plate thickness, in.WPw = wear plate width, in.wt = weight, lbsY = yield stress of material, psi.

DEFINITIONS, Calculations based on L.P. Zicks analysis presentation in 1951

Client: ACME

Date

5/9/2012Vessel:ACAX80005 Project No: 20090.039

MATERIAL TOUGHNESS EVALUATION PER UCS-66

Component:Shell

req. thickness0.357

STEP 1 Component Variables

nom. thickness

Impact Testing Not Required

tn 0.732

tr

joint efficiency 0.80E*

corrosion allowance0.375cof Fig.UCS-66 ACurve

Min. Metal Temperature from Fig.UCS-66 14MDMT

STEP 2 Select MDMT from Fig.UCS-66

STEP 3 Determine Ratio

°F, original design-20MDMT

applied tensile stress10193

allowable stess valueS 23100

S*

joint efficiency used in tr0.70E

joint efficiency from Step 10.80E*

FIG. UCS-66.2 DIAGRAM OF UCS-66 RULES FOR DETERMINING LOWEST MINIMUM DESIGN METAL TEMPERATURE (MDMT) WITHOUT IMPACT TESTING

MAWP MAP

additional reduction in temperature 56 °F

STEP 4 Select MDMT from Fig.UCS-66.1 using ratio determined in STEP 3

Minimum Design Metal Temperature-42MDMT

Material CS Unknown

S*E* / SE0.504Ratio

Application: Design Conditions

psi psi

in.

in.

in.

°F

psi

psi

°F

YesExempt?

1) Material being evaluated is AAR TC-128 Gr. B (DOT Spec. 112A400W) which is not listed in the curves of ASME Sect. VIII, Div. 1 UCS-66. This evaluation was based on unknown, fine grain, normalized carbon steel which is qualified for use to -50ºF per AAR Manual App. M para 5.1.2 2) S* = Combined tensile stress from longitudinal bending and internal pressure.

Note:

Page 1 of 3Project No: 20090.039 Author: JLW

Component:Heads 1&2

req. thickness0.406


nom. thickness


tn 0.781

tr


corrosion allowance0.375cof Fig.UCS-66 BCurve







S*




MAWP MAP

additional reduction in temperature °F


Minimum Design Metal TemperatureMDMT

Material CS Unknown

S*E* / SE0.158Ratio


psi psi

in.

in.

in.

°F

psi

psi

°F

YesExempt?

1) Material being evaluated is AAR TC-128 Gr. B (DOT Spec. 112A400W) which is not listed in the curves of ASME Sect. VIII, Div. 1 UCS-66. This evaluation was based on unknown, fine grain, normalized carbon steel which is qualified for use to -50ºF per AAR Manual App. M para 5.1.2 2) See UCS 66(b)3 for ratio less than 0.35 in Step 3. Not further evaluation required for this component.

Note:


Component:MW Boss

req. thickness0.085


nom. thickness


tn 4.50

tr


corrosion allowance0.375cof Fig.UCS-66 BCurve







S*




25MAWP 6680MAP

additional reduction in temperature °F


Minimum Design Metal TemperatureMDMT

Material CS - A516 70

MAWP / MAP0.004Ratio


psi psi

in.

in.

in.

°F

psi

psi

°F

YesExempt?

1) Material being evaluated is unknown; therefore, lowest grade material allowed by DOT regulations (A 516 70) for railcar material was assumed for this evaluation (reference CFR-Title 49 179.100-7).2) See UCS 66(b)3 for ratio less than 0.35 in Step 3. Not further evaluation required for this component.

Note:


Applied Stress to vessel components in corroded condition MDMTS P R/D t E Long Bending Stress/E Total S*

Shell S = PR /t+ .6P 4192 25 59.643 0.357 0.7 4201 6001 10193Head S = PD/2t + .2P 3651 25 118.438 0.406 0.85 LBS LBS/E 3651Noz S = PR /t+ .6P 74 25 9.75 4.125 1 74

1) Vessel Layout Drawing

Appendix B

Drawings

Page 3 of 9Project No.: 20090.039 Author: Jeff Walling

1) DOT CFR Title 49 Summary

2) Fatigue Gracking TC-128 B

3) AAR TC128 Spec Sheet

Appendix C

Supplemental Supporting Documents


Home Page > Executive Branch > Code of Federal Regulations > Electronic Code of Federal Regulations

e-CFR Data is current as of May 7, 2012

Title 49: Transportation PART 179—SPECIFICATIONS FOR TANK CARS

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Subpart C—Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120)

§ 179.100 General specifications applicable to pressure tank car tanks.

§ 179.100-1 Tanks built under these specifications shall comply with the requirements of §§179.100, 179.101 and when applicable, §§179.102 and 179.103.

§ 179.100-3 Type.

(a) Tanks built under this specification shall be fusion-welded with heads designed convex outward. Except as provided in §179.103 they shall be circular in cross section, shall be provided with a manway nozzle on top of the tank of sufficient size to permit access to the interior, a manway cover to provide for the mounting of all valves, measuring and sampling devices, and a protective housing. Other openings in the tank are prohibited, except as provided in part 173 of this chapter, §§179.100–14, 179.101–1, 179.102 or §179.103.

(b) Head shields and shells of tanks built under this specification must be normalized. Tank car heads must be normalized after forming unless specific approval is granted for a facility's equipment and controls.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179–10, 36 FR 21344, Nov. 6, 1971; 65 FR 58632, Sept. 29, 2000; 74 FR 1802, Jan. 13, 2009]

§ 179.100-4 Insulation.

(a) If insulation is applied, the tank shell and manway nozzle must be insulated with an approved material. The entire insulation must be covered with a metal jacket of a thickness not less than 11 gauge (0.1196 inch) nominal (Manufacturers' Standard Gauge) and flashed around all openings so as to be weather-tight. The exterior surface of a carbon steel tank, and the inside surface of a carbon steel jacket must be given a protective coating.

(b) If insulation is a specification requirement, it shall be of sufficient thickness so that the thermal conductance at 60 °F is not more than 0.075 Btu per hour, per square foot, per degree F temperature differential. If exterior heaters are attached to tank, the thickness of the insulation over each heater element may be reduced to one-half that required for the shell.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179–10, 36 FR 21344, Nov. 6, 1971; Amdt. 179–50, 60 FR 49077, Sept. 21, 1995]

§ 179.100-6 Thickness of plates.

(a) The wall thickness after forming of the tank shell and heads must not be less than that specified in

Page 1 of 14Electronic Code of Federal Regulations:

5/9/2012http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=42d8cb2cd7517e55c9249df1189dc...

§179.101, nor that calculated by the following formula:

t = Pd / 2SE

Where:

d = Inside diameter in inches;

E = 1.0 welded joint efficiency; except for heads with seams=0.9;

P = Minimum required bursting pressure in p.s.i.;

S = Minimum tensile strength of plate material in p.s.i., as prescribed in §179.100–7;

t = Minimum thickness of plate in inches after forming.

(b) If plates are clad with material having tensile strength properties at least equal to the base plate, the cladding may be considered a part of the base plate when determining thickness. If cladding material does not have tensile strength at least equal to the base plate, the base plate alone shall meet the thickness requirement.

(c) When aluminum plate is used, the minimum width of bottom sheet of tank shall be 60 inches, measured on the arc, but in all cases the width shall be sufficient to bring the entire width of the longitudinal welded joint, including welds, above the bolster.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179–10, 36 FR 21344, Nov. 6, 1971]

§ 179.100-7 Materials.

(a) Steel plate: Steel plate materials used to fabricate tank shell and manway nozzle must comply with one of the following specifications with the indicated minimum tensile strength and elongation in the welded condition. The maximum allowable carbon content must be 0.31 percent when the individual specification allows carbon greater than this amount. The plates may be clad with other approved materials.

1Maximum stresses to be used in calculations.

2These specifications are incorporated by reference (IBR, see §171.7 of this subchapter).

(b) Aluminum alloy plate: Aluminum alloy plate material used to fabricate tank shell and manway nozzle must be suitable for fusion welding and must comply with one of the following specifications (IBR, see §171.7 of this subchapter) with its indicated minimum tensile strength and elongation in the welded condition. * * *

Specifications

Minimum tensile strength (p.s.i.) welded

condition1

Minimum elongation in 2 inches (percent) welded condition (longitudinal)

AAR TC 128, Gr. B

81,000 19

ASTM A 3022, Gr. B

80,000 20

ASTM A 5162 70,000 20

ASTM A 5372, Class 1

70,000 23



1For fabrication, the parent plate material may be 0, H112, or H32 temper, but design calculations must be based on minimum tensile strength shown.

20 temper only.

3Weld filler metal 5556 must not be used.

4Maximum stress to be used in calculations.

(c) High alloy steel plate. (1) High alloy steel plate must conform to the following specifications:

1Maximum stresses to be used in calculations.

(2)(i) High alloy steels used to fabricate tank must be tested in accordance with the following procedures in ASTM A 262, “Standard Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steel” (IBR, see §171.7 of this subchapter), and must exhibit corrosion rates not exceeding the following: * * *

Specifications

Minimum tensile strength (p.s.i.) 0 temper, welded

condition3,4

Minimum elongation in 2 inches (percent) 0 temper,

welded condition (longitudinal)

ASTM B 209, Alloy 50521

25,000 18


38,000 16


35,000 14


30,000 18


30,000 18


31,000 18


25,000 18

Specifications

Minimum tensile strength (p.s.i.)

welded condition1

Minimum elongation in 2 inches (percent) weld

metal (longitudinal)ASTM A 240/A 240M (incorporated by reference; see §171.7 of this subchapter), Type 304L

70,000 30

ASTM A 240/A 240M (incorporated by reference; see §171.7 of this subchapter), Type 316L

70,000 30



(ii) Type 304L and 316L test specimens must be given a sensitizing treatment prior to testing.

(d) All attachments welded to tank shell must be of approved material which is suitable for welding to the tank.

[Amdt. 179–10, 36 FR 21344, Nov. 6, 1971, as amended by Amdt. 179–32, 48 FR 27707, June 16, 1983; Amdt. 179–47, 58 FR 50237, Sept. 24, 1993; Amdt. 179–52, 61 FR 28679, June 5, 1996; Amdt 179–52, 61 FR 50255, Sept. 25, 1996; 66 FR 45186, Aug. 28, 2001; 67 FR 51660, Aug. 8, 2002; 68 FR 75759, Dec. 31, 2003]

§ 179.100-8 Tank heads.

(a) The tank head shape shall be an ellipsoid of revolution in which the major axis shall equal the diameter of the shell adjacent to the head and the minor axis shall be one-half the major axis.

(b) Each tank head made from steel which is required to be “fine grain” by the material specification, which is hot formed at a temperature exceeding 1700 °F., must be normalized after forming by heating to a temperature between 1550° and 1700 °F., by holding at that temperature for at least 1 hour per inch of thickness (30-minute minimum), and then by cooling in air. If the material specification requires quenching and tempering, the treatment specified in that specification must be used instead of the one specified above.

[29 FR 18995, Dec. 29, 1964. Redesignated, 32 FR 5606, Apr. 5, 1967 and amended by Amdt. 179–12, 39 FR 15038, Apr. 30, 1974]

§ 179.100-9 Welding.

(a) All joints shall be fusion-welded in compliance with the requirements of AAR Specifications for Tank Cars, appendix W (IBR, see §171.7 of this subchapter). Welding procedures, welders and fabricators shall be approved.

(b) [Reserved]

[29 FR 18995, Dec. 29, 1964, as amended at 65 FR 58632, Sept. 29, 2000; 68 FR 75759, Dec. 31, 2003]

§ 179.100-10 Postweld heat treatment.

(a) After welding is complete, steel tanks and all attachments welded thereto must be postweld heat treated as a unit in compliance with the requirements of AAR Specifications for Tank Cars, appendix W (IBR, see §171.7 of this subchapter).

(b) For aluminum tanks, postweld heat treatment is prohibited.

(c) Tank and welded attachments, fabricated from ASTM A 240/A 240M (IBR, see §171.7 of this subchapter), Type 304L or Type 316L materials do not require postweld heat treatment, but these materials do require a corrosion resistance test as specified in §179.100–7(c)(2).

[Amdt. 179–10, 36 FR 21345, Nov. 6, 1971, as amended by Amdt. 179–47, 58 FR 50238, Sept. 24, 1993; Amdt. 179–52, 61 FR 28679, June 5, 1996; 67 FR 51660, Aug. 8, 2002; 68 FR 75758 and 75759, Dec. 31, 2003]

§ 179.100-12 Manway nozzle, cover and protective housing.

(a) Manway nozzles must be of approved design of forged or rolled steel for steel tanks or of fabricated aluminum alloy for aluminum tanks, with an access opening of at least 18 inches inside diameter, or at

Test procedures Material Corrosion rate i.p.m.Practice B Types 304L and 316L 0.0040Practice C Type 304L 0.0020



least 14 inches by 18 inches around or oval. Each nozzle must be welded to the tank and the opening reinforced in an approved manner in compliance with the requirements of AAR Specifications for Tank Cars, appendix E, Figure E10 (IBR, see §171.7 of this subchapter).

(b) Manway cover shall be machined to approved dimensions and be of forged or rolled carbon or alloy steel, rolled aluminum alloy or nickel when required by the lading. Minimum thickness is listed in §179.101. Manway cover shall be attached to manway nozzle by through or stud bolts not entering tank, except as provided in §179.103–2(a).

(c) Except as provided in §179.103, protective housing of cast, forged or fabricated approved materials must be bolted to manway cover with not less than twenty3/4-inch studs. The shearing value of the bolts attaching protective housing to manway cover must not exceed 70 percent of the shearing value of bolts attaching manway cover to manway nozzle. Housing must have steel sidewalls not less than three-fourths inch in thickness and must be equipped with a metal cover not less than one-fourth inch in thickness that can be securely closed. Housing cover must have suitable stop to prevent cover striking loading and unloading connections and be hinged on one side only with approved riveted pin or rod with nuts and cotters. Openings in wall of housing must be equipped with screw plugs or other closures.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179–10, 36 FR 21345, Nov. 6, 1971; 68 FR 75760, Dec. 31, 2003]

§ 179.100-13 Venting, loading and unloading valves, measuring and sampling devices.

(a) Venting, loading and unloading valves must be of approved design, made of metal not subject to rapid deterioration by the lading, and must withstand the tank test pressure without leakage. The valves shall be bolted to seatings on the manway cover, except as provided in §179.103. Valve outlets shall be closed with approved screw plugs or other closures fastened to prevent misplacement.

(b) The interior pipes of the loading and unloading valves shall be anchored and, except as prescribed in §§173.314(j), 179.102 or 179.103, may be equipped with excess flow valves of approved design.

(c) Gauging device, sampling valve and thermometer well are not specification requirements. When used, they shall be of approved design, made of metal not subject to rapid deterioration by the lading, and shall withstand the tank test pressure without leakage. Interior pipes of the gauging device and sampling valve, except as prescribed in §§173.314(j), 179.102 or 179.103, may be equipped with excess flow valves of approved design. Interior pipe of the thermometer well shall be anchored in an approved manner to prevent breakage due to vibration. The thermometer well shall be closed by an approved valve attached close to the manway cover, or other approved location, and closed by a screw plug. Other approved arrangements that permit testing thermometer well for leaks without complete removal of the closure may be used.

(d) An excess flow valve as referred to in this specification, is a device which closes automatically against the outward flow of the contents of the tank in case the external closure valve is broken off or removed during transit. Excess flow valves may be designed with a by-pass to allow the equalization of pressures.

(e) Bottom of tank shell may be equipped with a sump or siphon bowl, or both, welded or pressed into the shell. Such sumps or siphon bowls, if applied, are not limited in size and must be made of cast, forged or fabricated metal. Each sump or siphon bowl must be of good welding quality in conjunction with the metal of the tank shell. When the sump or siphon bowl is pressed in the bottom of the tank shell, the wall thickness of the pressed section must not be less than that specified for the shell. The section of a circular cross section tank to which a sump or siphon bowl is attached need not comply with the out-of-roundness requirement specified in AAR Specifications for Tank Cars, appendix W, W14.06 (IBR, see §171.7 of this subchapter). Any portion of a sump or siphon bowl not forming a part of cylinder of revolution must have walls of such thickness and be so reinforced that the stresses in the walls caused by a given internal pressure are no greater than the circumferential stress that would exist under the same internal pressure in the wall of a tank of circular cross section designed in accordance with §179.100–6(a), but in no case shall the wall thickness be less than that specified in §179.101–1.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179–10, 36 FR 21345, Nov. 6, 1971; Amdt. 179–40, 52 FR 13046, Apr. 20, 1987; Amdt. 179–42, 54 FR 38798, Sept. 20, 1989; 65 FR 58632, Sept. 29, 2000; 68 FR 48571, Aug. 14, 2003; 68 FR 75760, Dec. 31, 2003]

§ 179.100-14 Bottom outlets.



(a) Bottom outlets for discharge of lading is prohibited, except as provided in §179.103–3. If indicated in §179.101, tank may be equipped with a bottom washout of approved construction. If applied, bottom washout shall be in accordance with the following requirements;

(1) The extreme projection of the bottom washout equipment may not be more than that allowed by appendix E of the AAR Specifications for Tank Cars (IBR, see §171.7 of this subchapter).

(2) Bottom washout shall be of cast, forged or fabricated metal and shall be fusion-welded to the tank. It shall be of good weldable quality in conjunction with metal of tank.

(3) If the bottom washout nozzle extends 6 inches or more from shell of tank, a V-shaped breakage groove shall be cut (not cast) in the upper part of the outlet nozzle at a point immediately below the lowest part of the inside closure seat or plug. In no case may the nozzle wall thickness at the root of the “V” be more than1/4-inch. Where the nozzle is not a single piece, provision shall be made for the equivalent of the breakage groove. The nozzle must be of a thickness to insure that accidental breakage will occur at or below the “V” groove or its equivalent. On cars without continuous center sills, the breakage groove or its equivalent may not be more than 15 inches below the tank shell. On cars with continuous center sills, the breakage groove or its equivalent must be above the bottom of the center sill construction.

(4) The closure plug and seat shall be readily accessible or removable for repairs.

(5) The closure of the washout nozzle must be equipped with a3/4-inch solid screw plug. Plug must be attached by at least a1/4-inch chain.

(6) Joints between closures and their seats may be gasketed with suitable material.

(b) [Reserved]

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179–10, 36 FR 21345, Nov. 6, 1971; Amdt. 179–40, 52 FR 13046, Apr. 20, 1987; 66 FR 45186, Aug. 28, 2001; 68 FR 75760, Dec. 31, 2003]

§ 179.100-16 Attachments.

(a) Reinforcing pads must be used between external brackets and shells if the attachment welds exceed 6 linear inches of1/4-inch fillet or equivalent weld per bracket or bracket leg. When reinforcing pads are used, they must not be less than one-fourth inch in thickness, have each corner rounded to a 1-inch minimum radius, and be attached to the tank by continuous fillet welds except for venting provisions. The ultimate shear strength of the bracket-to-reinforcing pad weld must not exceed 85 percent of the ultimate shear strength of the reinforcing pad-to-tank weld.

(b) Attachments not otherwise specified shall be applied by approved means.


§ 179.100-17 Closures for openings.

(a) Closures shall be of approved design and made of metal not subject to rapid deterioration by the lading. Plugs, if used, shall be solid, with NPT threads, and shall be of a length which will screw at least six threads inside the face of fitting or tank.

(b) [Reserved]

§ 179.100-18 Tests of tanks.

(a) Each tank shall be tested by completely filling tank and manway nozzle with water or other liquid having similar viscosity, at a temperature which shall not exceed 100 °F during the test; and applying the pressure prescribed in §179.101. The tank shall hold the prescribed pressure for at least 10 minutes without leakage or evidence of distress.

(b) Insulated tanks shall be tested before insulation is applied.



(c) Caulking of welded joints to stop leaks developed during the foregoing test is prohibited. Repairs in welded joints shall be made as prescribed in AAR Specifications for Tank Cars, appendix W (IBR, see §171.7 of this subchapter).

(d) Testing of exterior heaters is not a specification requirement.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967; 66 FR 45186, Aug. 28, 2001; 68 FR 75760, Dec. 31, 2003]

§ 179.100-19 Tests of safety relief valves.

(a) Each valve shall be tested by air or gas for compliance with §179.15 before being put into service.

(b) [Reserved]

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, as amended at 62 FR 51561, Oct. 1, 1997]

§ 179.100-20 Stamping.

(a) To certify that the tank complies with all specification requirements, each tank shall be plainly and permanently stamped in letters and figures at least3/8inch high into the metal near the center of both outside heads as follows:

(b) [Reserved]

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179–10, 36 FR 21346, Nov. 6, 1971; Amdt. 179–52, 61 FR 28679, June 5, 1996; 65 FR 50463, Aug. 18, 2000]

§ 179.101 Individual specification requirements applicable to pressure tank car tanks.

Editorial Note: At 66 FR 45186, Aug. 28, 2001, an amendment published amending a table in §179.101. No text or table appears in §179.101.

§ 179.101-1 Individual specification requirements.

In addition to §179.100, the individual specification requirements are as follows:

Example of required stampingSpecification DOT-105A100WMaterial ASTM A 516Cladding material (if any) ASTM A240–304Tank builder's initials CladDate of original test ABCCar assembler (if other than tanker builder) 00–0000

DEF

DOT specification Insulation

Bursting pressure

(psig)

Minimum plate

thickness (inches)

Test pressure

(psig)

Manway cover

thicknessBottom outlet

Bottom washout

Reference(179.***)

105A100ALW Yes 500 5/8 100 22 1/2 No No105A200ALW Yes 500 5/8 200 22 1/2 No No



1When steel of 65,000 to 81,000 p.s.i. minimum tensile strength is used, the thickness of plates shall be not less than 5/8 inch, and when steel of 81,000 p.s.i. minimum tensile strength is used, the minimum thickness of plate shall be not less than 9/16 inch.

2When approved material other than aluminum alloys are used, the thickness shall be not less than 2 1/4 inches.

3When steel of 65,000 p.s.i. minimum tensile strength is used, minimum thickness of plates shall be not less than 1/2 inch.

4Tank cars not equipped with a thermal protection or an insulation system used for the transportation of a Class 2 (compressed gas) material must have at least the upper two-thirds of the exterior of the tank, including manway nozzle and all appurtenances in contact with this area, finished with a reflective coat of white paint.

5For inside diameter of 87 inches or less, the thickness of plates shall be not less than 1/2 inch.

6See AAR Specifications for Tank Cars, appendix E, E4.01 (IBR, see §171.7 of this subchapter), and §179.103–2.

105A300ALW Yes 750 5/8 300 22 5/8 No No105A100W Yes 500 39/16 100 2 1/4 No No105A200W Yes 500 39/16 200 2 1/4 No No105A300W Yes 750 111/16 300 72 1/4 No No105A400W Yes 1,000 111/16 400 72 1/4 No No105A500W Yes 1,250 111/16 500 2 1/4 No No 102–1,

102–2105A600W Yes 1,500 111/16 600 2 1/4 No No 102–4,

102–17109A100ALW Optional 500 5/8 100 22 1/2 No Optional109A200ALW Optional 500 5/8 200 22 1/2 No Optional109A300ALW Optional 750 5/8 300 22 5/8 No Optional109A300W Optional 500 111/16 300 2 1/4 No Optional112A200W Optional4 500 3,59/16 200 2 1/4 No No112A340W Optional4 850 111/16 340 2 1/4 No No112A400W Optional4 1,000 111/16 400 2 1/4 No No112A500W Optional4 1,250 111/16 500 2 1/4 No No114A340W Optional4 850 111/16 340 6 Optional Optional 103114A400W Optional4 1,000 111/16 400 6 Optional Optional 103120A200ALW Yes 500 5/8 200 22 1/2 Optional Optional 103120A100W Yes 500 39/16 100 2 1/4 Optional Optional 103120A200W Yes 500 39/16 200 2 1/4 Optional Optional 103120A300W Yes 750 111/16 300 2 1/4 Optional Optional 103120A400W Yes 1,000 111/16 400 2 1/4 Optional Optional 103120A500W Yes 1,250 111/16 500 2 1/4 Optional Optional 103



7When the use of nickel is required by the lading, the thickness shall not be less than two inches.

[Amdt. 179–52, 61 FR 28679, June 5, 1996 as amended at 66 FR 45390, Aug. 28, 2001; 68 FR 75760, Dec. 31, 2003]

§ 179.102 Special commodity requirements for pressure tank car tanks.

(a) In addition to §§179.100 and 179.101 the following requirements are applicable:

(b) [Reserved]

§ 179.102-1 Carbon dioxide, refrigerated liquid.

(a) Tank cars used to transport carbon dioxide, refrigerated liquid must comply with the following special requirements:

(1) All plates for tank, manway nozzle and anchorage of tanks must be made of carbon steel conforming to ASTM A 516/A 516M (IBR, see §171.7 of this subchapter), Grades 55, 60, 65, or 70, or AAR Specification TC 128–78, Grade B. The ASTM A 516/A 516M plate must also meet the Charpy V-Notch test requirements of ASTM A 20/A 20M (see table 16) (IBR, see §171.7 of this subchapter) in the longitudinal direction of rolling. The TC 128 plate must also meet the Charpy V-Notch energy absorption requirements of 15 ft.-lb. minimum average for 3 specimens, and 10 ft.-lb. minimum for one specimen, at minus 50 °F in the longitudinal direction of rolling in accord with ASTM A 370 (IBR, see §171.7 of this subchapter). Production-welded test plates prepared as required by W4.00 of AAR Specifications for Tank Cars, appendix W (IBR, see §171.7 of this subchapter), must include impact test specimens of weld metal and heat-affected zone. As an alternate, anchor legs may be fabricated of stainless steel, ASTM A 240/A 240M Types 304, 304L, 316 or 316L, for which impact tests are not required.

(2)–(6) [Reserved]

(b) [Reserved]

[29 FR 18995, Dec. 29, 1964]

Editorial Note: For Federal Register citations affecting §179.102–1, see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at www.fdsys.gov.

§ 179.102-2 Chlorine.

(a) Each tank car used to transport chlorine must comply with all of the following:

(1) Tanks must be fabricated from carbon steel complying with ASTM Specification A 516 (IBR, see §171.7 of this subchapter), Grade 70, or AAR Specification TC 128, Grade A or B.

(2)–(3) [Reserved]

(b) [Reserved]

[Amdt. 179–7, 36 FR 14697, Aug. 10, 1971; Amdt. 179–10, 36 FR 21346, Nov. 6, 1971, as amended by Amdt. 179–25, 44 FR 20433, Apr. 5, 1979; Amdt. 179–40, 52 FR 13046, Apr. 20, 1987; Amdt. 179–45, 55 FR 52728, Dec. 21, 1990; Amdt. 179–52, 61 FR 28680, June 5, 1996; 68 FR 75760, Dec. 31, 2003]

§ 179.102-3 Materials poisonous by inhalation.

(a) Each tank car built after March 16, 2009 for the transportation of a material poisonous by inhalation must, in addition to the requirements prescribed in §179.100–12(c), enclose the service equipment within a protective housing and cover.

(1) Tank cars must be equipped with a top fitting protection system and nozzle capable of sustaining, without failure, a rollover accident at a speed of 9 miles per hour, in which the rolling protective housing strikes a stationary surface assumed to be flat, level and rigid and the speed is determined as a linear



velocity, measured at the geometric center of the loaded tank car as a transverse vector. Failure is deemed to occur when the deformed protective housing contacts any of the service equipment or when the tank retention capability is compromised.

(2) As an alternative to the tank car top fitting protection system requirements in paragraph (a)(1) of this section, the tank car may be equipped with a system that prevents the release of product from any top fitting in the case of an accident where any top fitting would be sheared off. The tank nozzle must meet the performance standard in paragraph (a)(1) of this section and only mechanically operated excess flow devices are authorized.

(b) An application for approval of a tank car built in accordance with §173.244(a)(3) or §173.314(d) must include a demonstration, through engineering analysis, that the tank jacket and support structure system, including any anchors and support devices, is capable of withstanding a 6 mile per hour coupling without jacket shift such that results in damage to the nozzle.

[74 FR 1802, Jan. 13, 2009]

§ 179.102-4 Vinyl fluoride, stabilized.

Each tank used to transport vinyl fluoride, stabilized, must comply with the following special requirements:

(a) All plates for the tank must be fabricated of material listed in paragraph (a)(2) of this section, and appurtenances must be fabricated of material listed in paragraph (a)(1) or (a)(2) of this section.

(1) Stainless steel, ASTM A 240/A 240M (IBR, see §171.7 of this subchapter), Type 304, 304L, 316 or 316L, in which case impact tests are not required; or

(2) Steel complying with ASTM Specification A 516 (IBR, see §171.7 of this subchapter); Grade 70; ASTM Specification A 537 (IBR, see §171.7 of this subchapter), Class 1; or AAR Specification TC 128, Grade B, in which case impact tests must be performed as follows:

(i) ASTM A 516/A 516M and A 537/A 537M material must meet the Charpy V-Notch test requirements, in longitudinal direction of rolling, of ASTM A 20/A 20M (IBR, see §171.7 of this subchapter).

(ii) AAR Specification TC 128 material must meet the Charpy V-Notch test requirements, in longitudinal direction of rolling, of 15 ft.-lb. minimum average for 3 specimens, with a 10 ft.-lb. minimum for any one specimen, at minus 50 °F or colder, in accordance with ASTM A 370 (IBR, see §171.7 of this subchapter).

(iii) Production welded test plates must—

(A) Be prepared in accordance with AAR Specifications for Tank Cars, appendix W, W4.00 (IBR, see §171.7 of this subchapter);

(B) Include impact specimens of weld metal and heat affected zone prepared and tested in accordance with AAR Specifications for Tank Cars, appendix W, W9.00; and

(C) Meet the same impact requirements as the plate material.

(b) Insulation must be of approved material.

(c) Excess flow valves must be installed under all liquid and vapor valves, except safety relief valves.

(d) A thermometer well may be installed.

(e) Only an approved gaging device may be installed.

(f) A pressure gage may be installed.

(g) Aluminum, copper, silver, zinc, or an alloy containing any of these metals may not be used in the tank construction, or in fittings in contact with the lading.



(h) The jacket must be stenciled, adjacent to the water capacity stencil,

MINIMUM OPERATING TEMPERATURE _ °F.

(i) The tank car and insulation must be designed to prevent the vapor pressure of the lading from increasing from the pressure at the maximum allowable filling density to the start-to-discharge pressure of the reclosing pressure relief valve within 30 days, at an ambient temperature of 90 °F.

[Amdt. 179–32, 48 FR 27707, June 16, 1983, as amended at 49 FR 24317, June 12, 1984; 49 FR 42736, Oct. 24, 1984; Amdt. 179–45, 55 FR 52728, Dec. 21, 1990; Amdt. 179–52, 61 FR 28680, June 5, 1996; 65 FR 58632, Sept. 29, 2000; 66 FR 33452, June 21, 2001; 66 FR 45186, 45390, Aug. 28, 2001; 67 FR 51660, Aug. 8, 2002; 68 FR 75758, 75760 Dec. 31, 2003]

§ 179.102-17 Hydrogen chloride, refrigerated liquid.

Each tank car used to transport hydrogen chloride, refrigerated liquid must comply with the following special requirements:

(a) The tank car must comply with Specification DOT-105J600W and be designed for loading at minus 50 °F. or colder.

(b) All plates for the tank must be fabricated of material listed in paragraph (b)(2) of this section, and appurtenances must be fabricated of material listed in paragraph (b)(1) or (b)(2) of this section.

(1) Stainless steel, ASTM A 240/A 240M (IBR, see §171.7 of this subchapter), Type 304, 304L, 316, or 316L, in which case impact tests are not required; or

(2) Steel conforming to ASTM A 516/A 516M (IBR, see §171.7 of this subchapter), Grade 70; ASTM A 537/A 537M, (IBR, see §171.7 of this subchapter) Class 1; or AAR Specification TC 128, Grade B in which case impact tests must be performed as follows:

(i) ASTM A 516/A 516M and A 537/A 537M material must meet the Charpy V-notch test requirements, in longitudinal direction of rolling, of ASTM A 20/A 20M (IBR, see §171.7 of this subchapter).

(ii) AAR Specification TC 128 material must meet the Charpy V-notch test requirements, in longitudinal direction of rolling of 15 ft.-lb. minimum average for 3 specimens, with a 10 ft.-lb. minimum for any one specimen, at minus 50 °F or colder, in accordance with ASTM A 370 (IBR, see §171.7 of this subchapter).

(iii) Production welded test plates must—

(A) Be prepared in accordance with AAR Specifications for Tank Cars, appendix W, W4.00 (IBR, see §171.7 of this subchapter);

(B) include impact test specimens of weld metal and heat affected zone prepared and tested in accordance with AAR Specifications for Tank Cars, appendix W, W9.00; and

(C) meet the same impact requirements as the plate material.

(c) Insulation must be of approved material.

(d) Pressure relief valves must be trimmed with monel or other approved material and equipped with a rupture disc of silver, polytetrafluoroethylene coated monel, or tantalum. Each pressure relief device shall have the space between the rupture disc and the valve vented with a suitable auxiliary valve. The discharge from each pressure relief valve must be directed outside the protective housing.

(e) Loading and unloading valves must be trimmed with Hastelloy B or C, monel, or other approved material, and identified as “Vapor” or “Liquid”. Excess flow valves must be installed under all liquid and vapor valves, except safety relief valves.

(f) A thermometer well may be installed.



(g) Only an approved gaging device may be installed.

(h) A sump must be installed in the bottom of the tank under the liquid pipes.

(i) All gaskets must be made of, or coated with, polytetrafluoroethylene or other approved material.

(j) The tank car tank may be equipped with exterior cooling coils on top of the tank car shell.

(k) The jacket must be stenciled, adjacent to the water capacity stencil,

MINIMUM OPERATING TEMPERATURE _ °F.

(l) The tank car and insulation must be designed to prevent the pressure of the lading from increasing from the pressure at the maximum allowable filling density to the start-to-discharge pressure of the pressure relief valve within 30 days, at an ambient temperature of 90° F.

(m) Except as provided in §173.314(d), tank cars built on or after March 16, 2009 used for the transportation of hydrogen chloride, refrigerated liquid, must meet the applicable authorized tank car specification listed in §173.314(c).

[Amdt. 179–32, 48 FR 27708, June 16, 1983, as amended at 48 FR 50441, Nov. 1, 1983; 49 FR 24317, June 12, 1984; 49 FR 42736, Oct. 24, 1984; Amdt. 179–45, 55 FR 52728, Dec. 21, 1990; 66 FR 45390, Aug. 28, 2001; 67 FR 51660, Aug. 8, 2002; 68 FR 75758, 75760, Dec. 31, 2003; 74 FR 1802, Jan. 13, 2009]

§ 179.103 Special requirements for class 114A * * * tank car tanks.

(a) In addition to the applicable requirements of §§179.100 and 179.101 the following requirements shall be complied with:

(b) [Reserved]

§ 179.103-1 Type.

(a) Tanks built under this section may be of any approved cross section.

(b) Any portion of the tank shell not circular in cross section shall have walls of such thickness and be so reinforced that the stresses in the walls caused by a given internal pressure are no greater than the circumferential stresses which would exist under the same internal pressure in the wall of a tank of circular cross section designed in accordance with paragraphs §179.100–6 (a) and (b), but in no case shall the wall thickness be less than that specified in §179.101.

(c) [Reserved]

(d) Valves and fittings need not be mounted on the manway cover.

(e) One opening may be provided in each head for use in purging the tank interior.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179–50, 60 FR 49077, Sept. 21, 1995]

§ 179.103-2 Manway cover.

(a) The manway cover must be an approved design.

(b) If no valves or measuring and sampling devices are mounted on manway cover, no protective housing is required.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, and amended by Amdt. 179–50, 60 FR 49077, Sept. 21, 1995]



§ 179.103-3 Venting, loading and unloading valves, measuring and sampling devices.

(a) Venting, loading and unloading valves, measuring and sampling devices, when used, shall be attached to a nozzle or nozzles on the tank shell or heads.

(b) These valves and appurtenances must be grouped in one location and, except as provided in §179.103–5, must be equipped with a protective housing with cover, or may be recessed into tank shell with cover. An additional set grouped in another location may be provided. Protective housing with cover, when used, must have steel sidewalls not less than three-fourths inch in thickness and a metal cover not less than one-fourth inch in thickness that can be securely closed. Underframe sills are an acceptable alternate to the protective housing cover, provided the arrangement is of approved design. For fittings recessed into tank shell, protective cover must be metal and not less than one-fourth inch in thickness.

(c) When tank car is used to transport liquefied flammable gases, the interior pipes of the loading, unloading, and sampling valves must be equipped with excess flow valves of approved design except when quick closing internal valves of approved design are used. When the interior pipe of the gaging device provides a means for the passage of lading from the interior to the exterior of the tank, it must be equipped with an excess flow valve of approved design or with an orifice not exceeding 0.060 inch.


§ 179.103-4 Safety relief devices and pressure regulators.

(a) Safety relief devices and pressure regulators must be located on top of the tank near the center of the car on a nozzle, mounting plate or recess in the shell. Through or stud bolts, if used, must not enter the tank.

(b) Metal guard of approved design must be provided to protect safety relief devices and pressure regulators from damage.

[Amdt. 179–10, 36 FR 21348, Nov. 6, 1971]

§ 179.103-5 Bottom outlets.

(a) In addition to or in place of the venting, loading and unloading valves, measuring and sampling devices as prescribed in §179.103–3, tanks may be equipped with approved bottom outlet valves. If applied, bottom outlet valves must meet the following requirements:

(1) On cars with center sills, a ball valve may be welded to the outside bottom of the tank or mounted on a pad or nozzle with a tongue and groove or male and female flange attachment, but in no case shall the breakage groove or equivalent extend below the bottom flange of the center sill. On cars without continuous center sills, a ball valve may be welded to the outside bottom of the tank or mounted with a tongue and groove or male and female flange attachment on a pad attached to the outside bottom of the tank. The mounting pad must have a maximum thickness of 21/2inches measured on the longitudinal centerline of the tank. The valve operating mechanism must be provided with a suitable locking arrangement to insure positive closure during transit.

(2) When internal bottom outlet valve is used in liquefied flammable gas service, the outlet of the valve must be equipped with an excess flow valve of approved design, except when a quick-closing internal valve of approved design is used. Protective housing is not required.

(3) Bottom outlet must be equipped with a liquid tight closure at its lower end.

(b) Bottom outlet equipment must be of approved design and must meet the following requirements:

(1) The extreme projection of the bottom outlet equipment may not be more than allowed by appendix E of the AAR Specifications for Tank Cars (IBR, see §171.7 of this subchapter). All bottom outlet reducers and closures and their attachments shall be secured to the car by at least3/8inch chain, or its equivalent, except that bottom outlet closure plugs may be attached by1/4inch chain. When the bottom outlet closure is of the combination cap and valve type, the pipe connection to the valve shall be closed by a plug, cap, or approved quick coupling device. The bottom outlet equipment should include only the valve, reducers and closures that are necessary for the attachment of unloading fixtures. The permanent



attachment of supplementary exterior fittings must be approved by the AAR Committee on Tank Cars.

(2) To provide for the attachment of unloading connections, the discharge end of the bottom outlet nozzle or reducer, the valve body of the exterior valve, or some fixed attachment thereto, shall be provided with one of the following arrangements or an approved modification thereof. (See appendix E. Fig. E17 of the AAR Specifications for Tank Cars for illustrations of some of the possible arrangements.)

(i) A bolted flange closure arrangement including a minimum 1-inch NPT pipe plug (see Fig. E17.1) or including an auxiliary valve with a threaded closure.

(ii) A threaded cap closure arrangement including a minimum 1-inch NPT pipe plug (see Fig. E17.2) or including an auxiliary valve with a threaded closure.

(iii) A quick-coupling device using a threaded plug closure of at least 1-inch NPT or having a threaded cap closure with a minimum 1-inch NPT pipe plug (see Fig. E17.3 through E17.5). A minimum 1-inch auxiliary test valve with a threaded closure may be substituted for the 1-inch pipe plug (see Fig E17.6). If the threaded cap closure does not have a pipe plug or integral auxiliary test valve, a minimum 1-inch NPT pipe plug shall be installed in the outlet nozzle above the closure (see Fig. E17.7).

(iv) A two-piece quick-coupling device using a clamped dust cap must include an in-line auxiliary valve, either integral with the quick-coupling device or located between the primary bottom outlet valve and the quick-coupling device. The quick-coupling device closure dust cap or outlet nozzle shall be fitted with a minimum 1-inch NPT closure (see Fig. E17.8 and E17.9).

(3) The valve operating mechanism must be provided with a suitable locking arrangement to insure positive closure during transit.

(4) If the outlet nozzle extends 6 inches or more from shell of tank, a V-shaped breakage groove shall be cut (not cast) in the upper part to the outlet nozzle at a point immediately below the lowest part of value closest to the tank. In no case may the nozzle wall thickness at the roof of the “V” be more than1/4-inch. On cars without continuous center sills, the breakage groove or its equivalent may not be more than 15 inches below the tank shell. On cars with continuous center sills, the breakage groove or its equivalent must be above the bottom of the center sill construction.

(5) The valve body must be of a thickness which will insure that accidental breakage of the outlet nozzle will occur at or below the “V” groove, or its equivalent, and will not cause distortion of the valve seat or valve.

[Amdt. 179–10, 36 FR 21348, Nov. 6, 1971, as amended by Amdt. 179–40, 52 FR 13046, Apr. 20, 1987; Amdt. 179–41, 52 FR 36672, Sept. 30, 1987; Amdt. 179–50, 60 FR 49077, Sept. 21, 1995; Amdt. 179–52, 61 FR 28680, June 5, 1996; Amdt. 179–53, 61 FR 51342, Oct. 1, 1996; 66 FR 45186, Aug. 28, 2001; 68 FR 75761, Dec. 31, 2003]

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Section 508 / Accessibility



Fatigue Crack Growth Rate Behavior of Tank Car Steel TC-128B

Peter C. McKeighanJames H. Feiger

Southwest Research Institute6220 Culebra Rd.

San Antonio, TX 78238-5166210.522.3617 (PCM) 210.522.6881 (JHF)[email protected] [email protected]

William T. RiddellVolpe National Transportation Systems Center, DTS-76

55 BroadwayCambridge, MA 02142-1093

[email protected]

Key Words: Fatigue Crack Growth Rate, Railroad Tank Car, Structural Integrity,TC-128B, Damage Tolerance

INTRODUCTION

As part of an effort to apply damage tolerance concepts to railroad tank cars, the fatigue crack growth(FCG) behavior of two lots of TC-128B (similar to A612 Grade B steel) steel was investigated. Advancedtest control strategies were used to optimize testing, resulting in twenty-one FCG datasets using thirteenspecimens. In addition to the material lot difference, variables assessed include load ratio (R = 0.1, 0.6 and-1.0), orientation (L-T and L-S) and, indirectly, crack growth test technique (K-decreasing, -increasing,constant-Kmax with increasing-Kmin). The two material lots yielded essentially identical FCG properties forboth low and high R-ratio. The influence of R-ratio was slight, on the order of a 50 percent increase ingrowth rate at the higher 0.6 R-ratio when compared to low R-ratio conditions. The in-plane orientation(L-T) exhibits a growth rate approximately two times (2x) faster than the through-thickness orientation(L-S). Furthermore, constant Kmax test results suggest that the fatigue crack growth threshold isapproximately 2-3 ksi√in and 3-4 ksi√in for the L-T and L-S orientation, respectively. Finally, the datagenerated for TC-128B in the two orientations tested (a) agrees well with A612-Gr. B data extracted fromthe literature and (b) exhibits slightly slower growth rates than a generalized FCG response derived forcommon structural and low alloy steels.

BACKGROUND

Under normal service conditions, a railroad tank car is subjected to cyclic loads that can cause structuraldamage to the car. Fatigue cracking and structural failures in railroad tank cars have been documented sincethe mid-1980s(1). These cracks were detected as part of an inspection program implemented by the tank carindustry working in concert with the U.S. and Canadian regulatory bodies. Implementing performance-based inspection intervals could optimize safety and operating costs. Performance-based inspection intervalsare based on the time that it would take the largest crack that might be missed in an inspection to grow tofailure. This design approach utilizing inspection intervals is known as damage tolerance(2,3). A damagetolerance analysis (DTA) approach is desirable because it ensures that fatigue cracking does not lead tocatastrophic failure while insuring optimum maintenance efficiency by defining the periodic inspection rate.However, an accurate damage tolerant design requires extensive knowledge of the service loadingconditions, material(s), local stresses and geometric influences. One of the key parameters required in thistype of design is the fatigue crack growth rate behavior so that the speed of crack growth can be predictedunder service loading conditions.

Paris was the first to suggest a fracture mechanics approach to predicting fatigue crack growth rates(4).Paris noted a linear relationship between fatigue crack growth rate (da/dN) when plotted against cyclic stressintensity factor (∆K) on a log-log plot. In principle, this observation allows fatigue crack growth ratesobserved during laboratory tests to be used in design, since nearly all models for fatigue crack growth haveutilized ∆K as the primary predictor of crack growth rates. In practice, however, predicting fatigue crackgrowth rate requires more than simply the ∆K range since the underlying material behavior is fairly complex.For example, stress ratio (R, also called R-ratio and defined as the ratio of minimum to maximum load) andfatigue crack growth threshold (∆Kth) can haveconsiderable effect on growth rates(5). The fatigue crackgrowth threshold is the ∆K that defines when crackspropagate; at ∆K levels below ∆Kth, the crack growth iseffectively arrested.

Tank car steel TC-128B is used in the manufacture oftank car shells. A fatigue failure in a shell could directlyresult in a loss of lading; so the FCG behavior ofTC-128B is of concern. The purpose of this paper is topresent results from a series of tests designed tocharacterize fatigue crack growth behavior in TC-128B,as produced by two different manufacturers. Specifically,the effects of stress ratio, and orientation are investigatedunder a wide range of ∆K. These data will provide thebasis for future work toward developing models forpropagation of fatigue cracks under the complex stress,geometry, and environmental conditions that areencountered by railroad tank cars. Executing asystematic characterization effort is important to avoidthe situation shown in Figure 1. The wide scatter in FCGrate at a given ∆K, in this case for A36 steel usingnumerous datasets from the literature(6), is a source ofenormous uncertainty in a deterministic life prediction.

A36 steel34 sets of data1971-1987

10 10010-9

10-8

10-7

10-6

10-5

10-4

10-3

))))K, ksiooooin

da/d

N,

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cycl

e

Figure 1. FCG data scatter for A36 steel.

MATERIALS AND METHODS

Materials: Two tank car manufacturers supplied the plate material utilized during this program. The goalwas to process the two materials in a similar fashion and simulate tank car material currently in-service.Material type A (from Bethlehem Steel) is 0.781-inch thick and was received in a normalized form. Materialtype B (from U.S. Steel) is 0.813-inch thick with better controlled low-temperature fracture toughness and isused in cold-temperature cars. Material B was double normalized by first heating to 1655°F, holding for 30minutes and cooling to ambient temperature in still air followed by a repeat cycle at 1600°F. Both materialswere subsequently stress relieved by introducing into a 600°F furnace, heating at 400°F/hour to 1125°F,holding for 60 minutes and cooling to 600°F at a rate no greater than 500°F/hour. Cooling to ambienttemperature subsequently occurred in still air. The materials were stress relieved, since tank cars are stressrelieved during manufacture after welding.

The chemistries and tensile properties of each material lot are indicated in Tables I and II, respectively.Even though the lots were from different suppliers, the basic chemistry and properties were quite similar andwithin AAR specifications for TC-128B. The double normalized type B material exhibited a slight (1-2 ksi)decrease in strength when compared to the single normalized type A material. However, it is unknownwhether this is a consequence of different lots or the normalization scheme.

Table I. Measured chemistries for the two different materials and AAR TC-128B specification(7).

Matl C Mn P S Si Cu Ni Cr Mo V Al Nb Ti B N SnA .23 1.32 .023 .008 .37 .03 .01 .02 .07 .05 .03 <.01 <.01 <.0005 .0092 <.01B .23 1.33 .021 .006 .22 .05 .02 .17 .07 .07 .03 <.01 .01 <.0005 .0066 .01

spec <.29 .92-1.62 <.035 <.040 .13-.45 <.35 <.25 <.25 <.08 <.08 - - - - - -

Table II. Average room temperature tensile test properties of the two lots of TC-128Bmaterial used during testing.

Material Orient σσσσTS, ksi σσσσYS, ksi Elong, % RA, %A L 85.4 58.8 29 63

T 86.9 59.7 30 68B L 84.2 57.3 29 64

T 84.5 57.9 31 69AAR Specification 81-102 50 (min) 22 (min) -

Experimental Methods: Fatigue crack growth rate testing was performed on 10-kip servohydraulicmachines at frequencies between 5 and 20 Hz in accordance with the matrix of conditions in Table III. Alltesting was performed in lab air conditions with a relative humidity in the range of 40-75 percent. Fatiguecrack growth experiments were performed in accordance with the ASTM E647 test specification(8). Inaddition to the material lot difference, variables assessed include load ratio (R = 0.1, 0.6 and -1.0),orientation (L-T and L-S) and, indirectly, crack growth test technique (K-decreasing, -increasing, constant-Kmax with increasing-Kmin). Recall, the K-decreasing and -increasing tests are (executed sequentially)performed at a fixed R-ratio whereas the constant-Kmax, increasing-Kmin tests (for threshold level estimation)

vary from R = 0.1 (at high ∆K) to R = 0.9 at the completion of testing when ∆K approaches threshold.During constant Kmax testing, Kmax was fixed at 30 ksi√in.

The specimen thickness ranged from 0.225 to 0.250 inch. Three specimen geometries were employed: a3-inch wide compact tension, C(T), specimen, a 4-inch wide middle cracked tension, M(T), specimen and a0.75-inch wide single edge notched bend, SE(B) specimen. The two geometries other than the standard C(T)were utilized to accommodate R < 0 cycling, M(T), and testing in the thickness direction SE(B). Thecompacts and middle cracked tension specimens were in the L-T orientation whereas the bend specimenswere in the L-S orientation. All tests were performed in automated K-control using an FTA (FractureTechnology Associates, Bethlehem, PA) external computer control system. Although visual crack lengthmeasurements were periodically taken on all specimens, compliance (for the compact and bend specimens)and indirect PD [M(T) specimens] were used to control the test. Non-visual crack length measurements wereextensively validated during testing. In addition, back-face strain gages were used on the four-point bendand compact tension specimens to assist understanding closure conditions (however, crack closure results arebeyond the scope of this paper).

Table III. Summary of all of the fatigue crack growth tests performed during this testing.The symbol “→→→→” denotes constant conditions.

Test Type of Test Specimen Matl Load Type of Test PerformedID C(T) M(T) SE(B) Lot Ratio, R ∆∆∆∆K↓↓↓↓ ∆∆∆∆K↑↑↑↑ →→→→Kmax, ↑↑↑↑Kmin

TC-A-1A A 0.1TC-B-1A B 0.1TC-A-1B A 0.1TC-B-1B B 0.1TC-A-2A A 0.6TC-B-2A B 0.6TC-A-2B A 0.1-0.9TC-A-6 A -1.0TC-A-7 A -1.0TC-A-9 A 0.1TC-A-10 A 0.1TC-A-11 A 0.1-0.9TC-A-12 A 0.1

RESULTS AND DISCUSSION

Prior to examining the results, it is worthwhile to briefly review typical guidelines regarding repeatabilityin fatigue crack growth rate tests. A careful study of the ASTM standard(8) suggests that typical FCG ratevariability is approximately a factor of 2x for a given ∆K level. However, the round robin during which thisfactor was developed occurred over 25 years ago and it is believed that repeatability has improved since thattime*.

K-Gradient and Material Lot Effects: The pre-test expectation was that the effects of both of thesevariables would be slight. Nevertheless, it is critically important to experimentally assess this supposition. * As an aside, ASTM committee E08 is currently re-evaluating the issue of variability and performing a new round robin on FCGtesting.

Some representative test data are shown for a twosegment (K-decreasing and -increasing) high R-ratiospecimen in the L-T orientation in Figure 2. Whenperforming K-gradient testing, it is important to ensurethat the load history defined by the value of C, whereC = dK/Kda, does not influence the test resultsappreciably. It is clear from Figure 2 that theK-decreasing (C < 0) segment agrees remarkably wellwith the K-increasing segment. These data alsoindicate (a) how well the material replicates FCGbehavior in the Paris region and (b) the excellent levelof control achieved during the test. The obviousconclusion from Figure 2 is that the C values chosenfor the decreasing and increasing segments are suitableand do not bias the FCG results.

Scatter in fatigue crack growth rates such as thatshown for A36 data in Figure 1 is often attributed tomaterial lot variability. Admittedly, A36 steel is not atightly controlled grade and the data in Figure 1samples a wide range of variables including load ratio,orientation, temperature, corrosive environments andwelds (note that all of these variables are commonlyencountered in tank car structure). Nevertheless, the small influence of material lot (Type A or B) on FCGproperties for TC-128B is apparent from the low and high R-ratio data shown in Figure 3. The data for eachmaterial at each stress ratio consists of results from both increasing- and decreasing-∆K tests. The similaritybetween the FCG responses for Type A and B material is striking. At the lower R-ratio, greater variability,both within and between the datasets, is apparent. At higher R-ratio, when one expects less effects of crackclosure (a contributor to variability), the agreement between the material response is excellent.

Orientation and R-ratio Effects: Conventional wisdom about fatigue suggests that the influence of thesevariables should be greater than observed for the variables examined so far. Data from the in-plane L-T andthrough-thickness L-S orientation is shown for R = 0.1 in Figure 4. Although a greater level of variability isnoted for the L-S orientation (now more in accordance with ASTM guidelines at the higher growth rates), aclear difference between the two orientations is evident, especially in the Paris regime at higher ∆K levels.The FCG rates are slower in the L-S orientation, i.e., as the fatigue crack grows through the thickness of thematerial. This is significant since a high percentage of cracks in tank cars are typically surface initiated (dueto bending or residual stress effects) and grow through the thickness of the tank.

Constant R-ratio test results are contrasted in Figure 5 with the constant Kmax test data where, recall, theR-ratio is increased from 0.1 to 0.9 as ∆K is decreased. In the Paris regime of the data, the differencebetween low and high fixed R-ratio data is slight, typically on the order of 2x or less. This differenceincreases as the FCG rate decreases to less than 10-7 inch/cycle, regardless of orientation. The constant-KmaxFCG data in the L-T orientation follows expectation by mirroring the low R data at the start of the test (athigh ∆K) and then following the high R data until close to threshold. The high R-ratio threshold for the L-Torientation is in the range of 2-3 ksi√in whereas at low R-ratio it appears more on the order of 5-6 ksi√in.This trend is consistent with typical material behavior where ∆Kth decreases as R-ratio increases. This

∆∆∆∆K, ksi√√√√in

10 100

da/d

N, i

n/cy

cle

10-9

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10-5

10-4

C= -2 in-1

C= +6 in-1

Test ID: TC-B-2AOrientation: L-T R-ratio: 0.6

Figure 2. Effect of K-gradient on FCG behavior.

Figure 3. Effect of material lot on FCG behavior at both low and high R-ratio.

∆∆∆∆K, ksi√√√√in

10 100

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Type AType B

Orientation: L-T R-ratio: 0.1

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Type AType B

Orientation: L-T R-ratio: 0.6

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L-S orientationL-T orientation

R-ratio: 0.1

Figure 4. Influence of orientation on FCG behavior.

behavior for the L-T orientation is contrasted to the L-S casein Figure 5 where the constant-Kmax data suggests a highR-ratio threshold of 3-4 ksi√in.

Negative R-ratio data is shown with the previous L-T datafrom Figure 5 in Figure 6. Although the data appearssomewhat obscured from the other datasets on the plots, acareful observation of Figure 6 will show that the R = -1 datatypically exhibits the lowest growth rates for all conditions ata given ∆K. However, the overall difference between positiveand negative R-ratio is slight. Nevertheless, the observedtrend for tension-compression loading conditions is consistentwith that observed in other materials, including light alloysand steels, although the effect in most materials tends to begreater than the data shown herein.

Comparison of FCG Data with Other Sources: The fatiguecrack growth data shown so far exhibits excellent repeatabilityand all general trends are in accordance with expectation. It israre that the fatigue crack growth behavior of a candidatematerial is as well characterized as the TC-128B studiedherein. In this case, someone performing a DTA must use oneof the empirical relationships derived for steel. Three

∆∆∆∆K, ksi√√√√in

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cle

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R= 0.1R= 0.6R= -1

Orientation: L-T

Figure 6. FCG data for all R-ratio (L-T).

∆∆∆∆K, ksi√√√√in

10 100da

/dN

, in/

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10-8

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R= 0.1Const. K-max (R= 0.1-0.9)

Orientation: L-S

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R= 0.1R= 0.6Const. K-max (R= 0.1-0.9)

Orientation: L-T

Figure 5. Comparison between fixed R-ratio and constant Kmax FCG data for the L-T and L-S orientation.

relationships that are available(9-11), were used fordifferent strength levels and classifications of steel.Nevertheless, an examination of each clearly indicatesthat all are fairly similar. The most conservative ofthese relations (in terms of predicting a slightly higherfatigue crack growth rate at a given ∆K level) is thatderived by Hudak, Burnside and Chan(9) (HBC) forstructural and low alloy steels. This empiricalrelationship, divided up into low and high R-ratiobehavior (R > 0.5) is shown with the constant-Kmax FCGdata for the L-T and L-S orientations in Figure 7.

The L-T data in Figure 7 follows with expectation:at the start of the constant-Kmax test (i.e., at high ∆K) thedata is on the low R-ratio HBC line and the testprogresses and the data clearly moves toward the highR-ratio line, only diverging as ∆K decreases towardthreshold. The data for the L-S orientation is clearlydifferent. Even though R varied from 0.1 to 0.9 duringthe test, the data remains underneath the low R HBCline. This suggests that (a) the L-S orientation exhibitsvery slight R-ratio effects (since the data is parallel tothe HBC relation) and (b) the observed growth rate inthe L-S orientation is slower than predicted by the HBCrelationship.

Prior to the earlier described damage toleranceeffort, the tank car industry did not require FCG data forTC-128B material. Therefore, to our knowledge, noFCG data other than that shown herein is believed toexist for TC-128B. However, A612 material is fairlysimilar in composition and overall mechanicalproperties, although the microstructure and toughnessare not as well controlled in A612 as in TC-128B. Asurvey of the literature identified A612 FCG data in areference from Poon and Hoeppner(12). These data areplotted in Figure 8 with the TC-128B data band fromthe R = 0.1 and 0.6 data in Figure 6. Although thescatter in the literature data appears greater than in thecurrent data, the overall trend agrees reasonably well.Although it is difficult to tell definitively, the differencebetween FCG rates at R of 0.1 and 0.6 in the Poon datamay actually be less than we observed herein.

The observation of comparable fatigue crack growthproperties when contrasting 2000 vintage TC-128B and1977 vintage A612 is an interesting observation fromthe viewpoint of the aging tank car fleet. A recent

A612

))))K, ksiooooin10 100

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cycl

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10-8

10-7

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R = 0.1R = 0.6

TC-128B data band(R=0.1 and 0.6, L-T)

Figure 8. Comparison to literature data(12).

∆∆∆∆K, ksi√√√√in

10 100

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N, i

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cle

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10-4

L-T OrientationL-S Orientation

R-ratio: 0.1-0.9 (const. Kmax)

Low R

High R

Figure 7. Comparison to HBC relation(9).

source(13) indicates the average age of privately operated tank carts is 16.6 years with 42 percent of the fleetbuilt more than 20 years ago. If the A612 surveyed by Poon is consistent with the same vintage TC-128B,the FCG properties measured herein might be applicable to older TC-128B tanks in the fleet, not just thenewer generation. The hypothesized link between fatigue properties of 25-year-old A612 and those ofsimilar vintage TC-128B is as yet unsubstantiated. However, this is a reasonable possibility and worthy offurther attention.

The data included herein provides a baseline assessment of the FCG behavior of TC-128B. Usingrelations derived from these data in a DTA analysis is clearly more optimum than a standard relationshipsuch as the HBC model since it will yield more accurate life prediction. Nevertheless, it is worth noting thatthe data agrees generally with the HBC model and A612 data from the literature. One clear feature of thiswork is that the data extends all the way down to near threshold, a regime not included in any of the modelsin References 9-11 and critically important for accurate life prediction. Another significant aspect of thesedata is FCG behavior in the L-S orientation which is the critical orientation of primary concern if theobjective is to prevent lading leakage. Furthermore, the influence of environmental variables such asmoisture level and temperature on FCG properties is the subject of an ongoing effort extending these results.Finally, issues such as welds and variable amplitude loading influence FCG behavior in an as yetundetermined manner.

CONCLUSIONS

The fatigue crack growth behavior of TC-128B steel has been examined in detail herein. Two differentlots of TC-128B material, each in accordance with chemical and mechanical property guidelines, were testedand found to yield consistent FCG properties. The different K-gradient methods applied, although in thestrict sense outside the ASTM E647 guidelines, were shown to yield repeatable FCG data that wasindependent of the K-gradients used where other conditions were held constant. Moreover, the effects ofR-ratio and specimen orientation both yield an overall 2x factor on FCG rate for ∆K in the Paris regime:higher R-ratio data exhibited faster rates than low R-ratio data and the in-plane L-T orientation exhibited afaster growth rate than the through-thickness L-S orientation. The high R-ratio threshold behavior for thetwo orientations were of similar magnitude: 2-3 ksi√in and 3-4 ksi√in for the L-T and L-S orientation,respectively. As the FCG threshold was approached, the effects of R-ratio and orientation generallyincreased. Finally, a favorable comparison was made between the TC-128B FCG data measured herein andseveral data representations from the literature.

ACKNOWLEDGEMENTS

This research was supported by the Federal Railroad Administration Office of Research andDevelopment, program manager Ms. Claire Orth. Mr. Jose Pena is the project manager for FRA researchrelated to tank car safety. Appreciation is extended to Union Tank Car Company (Phil Daum, Al Henzi andFrank Reiner) and Trinity Industries (Tom Dalrymple) for donating the material used during this testing.The tireless efforts of Messrs. Dale Haines, Darryl Wagar, Harold Saldaña, Rick Fess and Forrest Campbellare kindly appreciated. Gratitude is also extended to Ms. Loretta Mesa for the assistance in preparing thismanuscript.

REFERENCES

1. “Inspection and Testing of Railroad Tank Cars,” NTSB/SIR-92/05, National Transportation SafetyBoard, Washington, D.C., 1992.

2. J. P. Gallagher, et al., “USAF Damage Tolerant Design Handbook,” AFWAL-TR-82-3073, May 1984.

3. “Damage Tolerance Assessment Handbook,” Vols. I and II, DOT-VNTSC-FAA-93-13.I, Oct. 1993.

4. P. C. Paris, M. P. Gomez, and W. P. Anderson, “A Rational Analytic Theory of Fatigue,” The Trend inEngineering, University of Washington, 1961.

5. S. Suresh, Fatigue of Materials, Cambridge University Press, Cambridge, UK, 1991.

6. J. W. Cardinal, P. C. McKeighan, and S. J. Hudak, “Damage Tolerance Analysis of Tank Car Stub SillCracking,” Southwest Research Institute Final Report No. 06-6965, prepared for the Tank Car Stub SillWorking Group, Nov. 1998.

7. “Appendix M – Specifications for Materials,” Manual of Standards and Recommended Practices,Section C – Part III, Specifications for Tank Cars, Specification M1002, The Association of AmericanRailroads, Sept. 1992.

8. Annual Book of ASTM Standards, Section 3: Metals Test Methods and Analytical Procedures, Vol.3.01, American Society for Testing and Materials, West Conshohocken, PA, 2000.

9. S. J. Hudak, Jr., O. H. Burnside, and K. S. Chan, “Analysis of Corrosion Fatigue Crack Growth inWelded Tubular Joints,” Journal of Energy Resources Technology, ASME, Vol. 107, June 1985.

10. E. D. Eason, J. D. Gilman, D. P. Jones, and S. P. Andrew, “Technical Basis for a Revised Crack GrowthRate Reference Curve for Ferritic Steels in Air,” Journal of Pressure Vessel Technology, ASME,Vol. 114, Feb. 1992.

11. N. Yazdani and P. Albrecht, “Crack Growth Rates of Structural Steel in Air and AqueousEnvironments,” Engineering Fracture Mechanics, Vol. 32, No. 6, 1989, pp. 997-1007.

12. C. Poon and C. W. Hoeppner, “The Effect of Temperature and R Ratio on Fatigue Crack Growth inA612 Grade B Steel,” Engineering Fracture Mechanics, Vol. 12, 1979, pp. 23-31.

13. Progressive Railroading, Vol. 44, No. 5, Trade Press Publishing Corporation, May 2001.

1) DOT Data Sheet

2) New Service MSDS

3) Old Service MSDS

Appendix D

Manufacturers Data Sheets


SIGMA-ALDRICH Material Safety Data Sheet Date Printed: 15/DEC/2004 Date Updated: 14/MAR/2004 Version 1.1 According to 91/155/EEC 1 - Product and Company Information Product Name FLUOROSULFONIC ACID, STAB. Product Number 47500 Company Sigma-Aldrich Pte Ltd #08-01 Citilink Warehouse Singapore 118529 Singapore Technical Phone # 65 271 1089 Fax 65 271 1571 2 - Composition/Information on Ingredients Product Name CAS # EC no Annex I Index Number FLUOROSULFONIC ACID 7789-21-1 232-149-4 016-018-00-7 Formula FSO3H Molecular Weight 100.07 AMU Synonyms Fluosulfonic acid 3 - Hazards Identification SPECIAL INDICATION OF HAZARDS TO HUMANS AND THE ENVIRONMENT Harmful by inhalation. Causes severe burns. 4 - First Aid Measures AFTER INHALATION If inhaled, remove to fresh air. If not breathing give artificial respiration. If breathing is difficult, give oxygen. AFTER EYE CONTACT Assure adequate flushing of the eyes by separating the eyelids with fingers. 5 - Fire Fighting Measures CONDITIONS OF FLAMMABILITY Water hydrolyzes material liberating acidic gas which in contact with metal surfaces can generate flammable and/or explosive hydrogen gas. EXTINGUISHING MEDIA Suitable: Noncombustible. Use extinguishing media appropriate to surrounding fire conditions. Unsuitable: Do not use water. SPECIAL RISKS Specific Hazard(s): Emits toxic fumes under fire conditions.

SPECIAL PROTECTIVE EQUIPMENT FOR FIREFIGHTERS Wear self-contained breathing apparatus and protective clothing to prevent contact with skin and eyes. 6 - Accidental Release Measures PERSONAL PRECAUTION PROCEDURES TO BE FOLLOWED IN CASE OF LEAK OR SPILL Evacuate area. PROCEDURE(S) OF PERSONAL PRECAUTION(S) Wear self-contained breathing apparatus, rubber boots, and heavy rubber gloves. METHODS FOR CLEANING UP Absorb on sand or vermiculite and place in closed containers for disposal. 7 - Handling and Storage HANDLING Directions for Safe Handling: Do not breathe vapor. Do not get in eyes, on skin, on clothing. Avoid prolonged or repeated exposure. STORAGE Conditions of Storage: Keep tightly closed. Store under nitrogen. Incompatible Materials: Do not allow contact with water Store at 2-8°C 8 - Exposure Controls / Personal Protection ENGINEERING CONTROLS Safety shower and eye bath. Use only in a chemical fume hood. GENERAL HYGIENE MEASURES Wash contaminated clothing before reuse. Discard contaminated shoes. Wash thoroughly after handling. PERSONAL PROTECTIVE EQUIPMENT Special Protective Measures: Wear appropriate government approved respirator, chemical-resistant gloves, safety goggles, other protective clothing. 9 - Physical and Chemical Properties Appearance Color: Colorless Form: Clear liquid Property Value At Temperature or Pressure pH N/A BP/BP Range 163 °C 760 mmHg MP/MP Range -87.3 °C Flash Point N/A Flammability N/A Autoignition Temp N/A Oxidizing Properties N/A Explosive Properties N/A Explosion Limits N/A Vapor Pressure 2.5 mmHg 25 °C SG/Density 1.84 g/cm3 Partition Coefficient N/A FLUKA - 47500 www.sigma-aldrich.com Page 2

Viscosity N/A Vapor Density 3.5 g/l Saturated Vapor Conc. N/A Evaporation Rate N/A Bulk Density N/A Decomposition Temp. N/A Solvent Content N/A Water Content N/A Surface Tension N/A Conductivity N/A Miscellaneous Data N/A Solubility N/A 10 - Stability and Reactivity STABILITY Materials to Avoid: Strong bases, Alcohols Avoid contact with metals. HAZARDOUS DECOMPOSITION PRODUCTS Hazardous Decomposition Products: Hydrogen fluoride. 11 - Toxicological Information RTECS NUMBER: LP0715000 SIGNS AND SYMPTOMS OF EXPOSURE Material is extremely destructive to tissue of the mucous membranes and upper respiratory tract, eyes, and skin. Inhalation may result in spasm, inflammation and edema of the larynxand bronchi, chemical pneumonitis, and pulmonary edema. Symptoms of exposure may include burning sensation, coughing, wheezing, laryngitis, shortness of breath, headache, nausea, and vomiting. To the best of our knowledge, the chemical, physical, and toxicological properties have not been thoroughly investigated. ROUTE OF EXPOSURE Multiple Routes: May be fatal if inhaled, swallowed, or absorbed through skin. 12 - Ecological Information No data available. 13 - Disposal Considerations SUBSTANCE DISPOSAL For small quantities: cautiously add to a large stirred excess of water. Adjust the pH to neutral, separate any insoluble solids or liquids and package them for hazardous-waste disposal. Flush the aqueous solution down the drain with plenty of water. The hydrolysis and neutralization reactions may generate heat and fumes which can be controlled by the rate of addition. Observe all federal, state, and local environmental regulations. 14 - Transport Information RID/ADR UN#: 1777 Class: 8 PG: I FLUKA - 47500 www.sigma-aldrich.com Page 3

Proper Shipping Name: Fluorosulphonic acid IMDG UN#: 1777 Class: 8 PG: I Proper Shipping Name: Fluorosulphonic acid Marine Pollutant: No Severe Marine Pollutant: No IATA UN#: 1777 Class: 8 PG: I Proper Shipping Name: Fluorosulphonic acid Inhalation Packing Group I: No 15 - Regulatory Information CLASSIFICATION AND LABELING ACCORDING TO EU DIRECTIVES ANNEX I INDEX NUMBER: 016-018-00-7 INDICATION OF DANGER: C Corrosive. R-PHRASES: 20 35 Harmful by inhalation. Causes severe burns. S-PHRASES: 26 45 In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. In case of accident or if you feel unwell, seek medical advice immediately (show the label where possible). COUNTRY SPECIFIC INFORMATION Germany WGK: 1 16 - Other Information WARRANTY The above information is believed to be correct but does not purport to be all inclusive and shall be used only as a guide. The information in this document is based on the present state of our knowledge and is applicable to the product with regard to appropriate safety precautions. It does not represent any guarantee of the properties of the product. Sigma-Aldrich Inc., shall not be held liable for any damage resulting from handling or from contact with the above product. See reverse side of invoice or packing slip for additional terms and conditions of sale. Copyright 2004 Sigma-Aldrich Co. License granted to make unlimited paper copies for internal use only. DISCLAIMER For R&D use only. Not for drug, household or other uses. FLUKA - 47500 www.sigma-aldrich.com Page 4