NBSIR 74-472

Analysis of Railroad Wheel Failure - Derailment at Richmond Hill, New York,

March 10, 1973

C. G. Interrante and G. E. Hicho

Mechanical Properties Section

Metallurgy Division

Institute for Materials Research

National Bureau of Standards

Washington, D. C. 20234

April 1974

Failure Analysis Report

Prepared for Federal Railroad Administration

Department of Transportation

Washington, D. C 20590
J
NBSIR 74-472

ANALYSIS OF RAILROAD WHEEL FAILURE -

DERAILMENT AT RICHMOND HILL, NEW YORK.

MARCH 10, 1973

C. G. Interrante and G. E. Hicho

Mechanical Properties Section

Metallurgy Division

Institute for Materials Research

National Bureau of Standards

Washington, D. C. 20234

April 1974

Failure Analysis Report

"This document has been prepared for the use of the Federal Railroad Administration, Department of Transportation, Washington, D. C. Responsibility

for its further use rests with that agency. NBS

requests that if release to the general public is contemplated, such action be taken only after consultation with the Office of Public Affairs at

the National Bureau of Standards.

\ IT) /

•"•r.u o»

U. S. DEPARTMENT OF COMMERCE, Frederick B. Dent, Secretarv NATIONAL BUREAU OF STANDARDS, Richard W. Roberts. Director

TABLE OF CONTENTS

Page

ABSTRACT iv

1. INTRODUCTION ' 1

2. PURPOSE 2

3. EXPERIMENTAL WORK 2

3.1 Sectioning of the Sample 2

3.2 Dimensional Measurements ' 3

3.3 Hardness Measurements 3

4. RESULTS 3

4.1 Macroscopic Observations 3

4.2 Hardness Measurements 4

4.3 Dimensional Measurements 5

4.4 Chemical Composition 5

4.5 Metallographic Examinations 5

4 . 6 Fractographic Examinations 6

5. DISCUSSION 7

6. RECOMMENDATIONS 7

TABLES

1. Comparison of the Dimensions Specified by AAR

and the Measured Values Taken from the Failed

Wheel.

2. Chemical Composition of the Sample Taken from

the Hub

i
FIGURES

1. Radial-Circumferential Section of the Fractured

Wheel, As Received at NBS

2. Fractured Wheel Section Showing the Three Parts

Into Which It Was Saw Cut.

3. ' Locations of Replicas, A Through M, Taken on

the Fracture Face.

4. Schematic Representation of the Location of

Brinell Hardness Impressions and Equivalent

Rockwell C Values (in parenthesis)

5. Photograph of Section 2 Showing the Brinell and

Rockwell C Hardness Impressions, the Etched

.; Sample, and the Saw Cut Between Pieces 2A and 2B

6. Results of Rockwell C Hardness Measurements Taken

on Section 2

7. Color Photographs of the Fracture Face of the Rim

Showing the Location of the Thermal Crack

(Initiation Site)

8. Thermal Checks Observed on the Tread of Section

2 After Hot Etching in 1 : 1 HCl.

9. Photomicrographs Taken at Region C (Figure 5)

Showing the Unaffected Base Metal of the Rim.

10. . Photomicrographs Taken at Region B (Figure 5)

Near the Inside of the HAZ Boundary.

11. Photomicrographs Taken at Region A (Figure 5)

Showing the Coarse-Grained Heat-Affected

Zone Observed Near the Tread.

12. SEM Fractographs Taken at Location C of Figure 3,

Showing the Predominately Quasi-Cleavage

Fracture Mode Observed in the Rim.

13. SEM Stereo-Pair Fractograph Taken at Location L

. of Figure 3, Showing the Prdcominately QuasiCleavage Fracture Mode Observed in the Rim.

ii
FIGURES

14. SEM Fractographs Taken at Location A of Figure

3, Showing Quasi-Cleavage Fracture and

Oxide Formations Observed Near the Boundary

of the Heat-Affected Zone of the Rim.

15. SEM Fractographs Taken from the Thermal Crack

Region (15a) and from the Hub Region (15b)

Showing Oxide Formations, Abraided Parts,

and Flat Fracture.

APPENDIX A - Specification: AAR-M-107 9-69

APPENDIX B - Specification: AAR Dimensions for Steel Wheel

of Design A-40 and Permissible Variations

in Dimensions not shown by Tolerances of

Individual Design Sheets.
ABSTR?^CT

At the request of the Standards and Procedures Division,

Federal Railroad Administration, Department of Transportation,

a failure analysis was made of a section of a railroad wheel

which had reportedly failed in service and had led to a derailment at Richmond Hill, New York. A section of the

failed wheel was sent to NBS where it was examined and

measurements made to determine the cause of the failure and

to determine whether or not the wheel had been produced in

accordance with applicable specifications.

The chemical composition, hardness, and dimensions of

the wheel section were measured. The results indicate that

the wheel met the requirements of the specifications. These

measurements and other observations indicate that the failure

occurred as a result of local overheating at the front of

the tread. It is believed that this overheating occurred in

service and resulted in the formation of a thermal crack in

this region. This crack subsequently propagated rapidly in

a radial direction through to the hub of the wheel.

iv
Analysis of Railroad Wheel Failure - Derailment at

Richmond Hill, New York, March 10, 1973

1. INTRODUCTION

A failure analysis of a section of a railroad wheel,

which failed in service and led to a derailment, was

requested by the Standards and Procedures Division, Federal

Railroad Administration, Department of Transportation. The

wheel sample was reported* to have been taken from a dieselelectric control unit. No. 609. This control unit, which

was the last unit of a passenger train, was derailed at

Richmond Hill, New York near the Dunton Tower on March 10,

1973 at 12:45 a.m. The derailment was apparently due to

the failure of this wheel.

Railroad investigators concluded* that the wheel had

broken from the rim to the hub, with a measured separation

of the rim of approximately 3/16 inch. This fracture

apparently permitted the wheel to move inward on the axle,

approximately 4 inches, thereby allowing the wheel to drop

from the rail. The wheel was reported to have been mounted

on the control unit in October, 1972, and it had been in

service for approximately 12,000 miles when the failure

occurred. The temperature at the nearest U.S. Weather

Bureau site, LaGuardia Airport, was reported to be 45°F

at 10 p.m. on March 9, 1973, and 40°F at 1 a.m. on

March 10, 1973.

A radial-circumferential section was torch cut from the

failed wheel and sent to the National Bureau of Standards

(NBS) for failure analyses. This section contained one of

the two radial-axial faces of the fracture, as is shown in

Figure 1.

The wheel was reported to have been produced in accordance

with the Association of American Railroad (AAR) Specification

M-107-69, for wrought, carbon steel wheels, and it was

located at the left No. 2 wheel position on the diesel-control

unit. The identification marking on the wheel (E) 74482 (B)

indicated that it had been produced as Class B, rim treated.

The wheel was of design A-4 0.**

Letter dated April 3, 1973 from R. E. Black, District

Inspector FRA, to C. R. Meyrick, Regional Director, FRA.

Reported to Mr . G. E. Hicho (NBS) by Mr. J. Sharp of

FRA in phone conversation October 4, 1973.

- 1 -
2 . PURPOSE

The objectives of this failure analysis were (1) to

determine the condition of the wheel in respect to the

specifications, to which it was produced, (2) to analyze

the fracture face so as to determine, if possible, the

initiation site of the fracture, and (3) to describe the

propagation behavior, as observed on the fracture face.

Another objective was to conduct tests deemed necessary to

obtain background information concerning the overall

question of the suitability of this steel for this

application

3 . EXPERIMENTAL WORK

Measurements were made of the dimensions, the hardness,

and the chemical composition of selected parts of the submitted sample, and the measured values were compared with

the AAR Specifications of designation "M-107-69 for Wheels,

Wrought Carbon Steel" to which the wheel had been produced.*

In addition, macroscopic and microscopic observations were

made on the wheel section submitted and on parts that were

saw cut from it.

3 . 1 Sectioning of the Sample

The as-received wheel section was saw cut into three

major parts, as shown in Figure 2. Section 1 contains the

entire radial -axial face of the fracture. It was visually

examined with the unaided eye and with the aid of a stereomicroscope at magnifications up to X3 . Selected locations

(A through M in Figure 3) of the fracture surface were then

replicated with cellulose acetate. The replicas were used

for scanning-electron-microscope (SEM) examinations of the

fracture surface. Replicas taken from A, C, D, L, and M

were considered sufficient for characterizing the fracture

surface and the other replicas therefore were not examined.

The remaining part of the sample (with the fracture face

removed) contained a smooth, saw-cut surface. This surface

was placed flat onto cardboard and the shape of the wheel

section was obtained by tracing the outline. This tracing

was useful in determining some of the dimensions of the

wheel. Where possible, these measurements were checked by

measurements taken directly from the wheel section.

See Appendix A.

- 2 -
After the dimensional measurements were taken, the wheel

section v/as further sectioned (saw cut) along the line that

divides sections 2 and 3, as shown in Figure 2. A 1-inch

slice, taken from the front of the hub as shown in Figures

2 and 3, was used for determinations of the chemical composition of the wheel. Section 2 was used for making hardness

measurements, and for microscopic and macroscopic studies

of the rim.

3 . 2 Dimensional Measurements

The measurements of the dimensions taken from the wheel

section and from the tracing made from it are shown in Table

1, along with the AAR Specifications on dimensions for design

A-40 wheels. We note that: (1) dimensions Oi and O2 were

calculated from an assumed value of 10-3/4 inches for the

bore, and (2) the measured values Ri and R2 do not represent

the values of the wheel in service, because these values were

taken on a wheel section and the act of sectioning affects

these dimensions.

3 . 3 Hardness Measurements

Brinell hardness measurements were made on the surface

of section 2 after polishing and etching the saw-cut surface.

The locations of the Brinell impressions are given in Figure

4, however, the three impressions shown nearest to the front

rim face v;ere actually taken on a radial-circumferential

surface of piece 2B, a piece that was cut from section 2 as

shown in Figure 5. - (Section 2 was cut into 2A and 2B, and

2B provided a small sample suitable for metallographic and

hardness studies.) Thus, the Brinell impressions taken on

this piece (2B) were on a plane perpendicular to the plane

shown in Figure 5. Similarly, Rockwell "C" hardness

measurements were taken on the surfaces of section 2 and on

piece 2B, at locations shown in Figure 6.

4. RESULTS

4.1 Macroscopic Observations

Macroscopically , the fracture surface appeared uniformly

rough over the entire face except for two regions that v/ere

somewhat smoother. These regions are near the tread and near

the bore, as is apparent in Figure 3. The smooth parts

extend for about 3/4 inches from the tread and from the bore.

- 3 -
In the rim, the rough parts of the fracture show many

lines with an apparent focal point on the tread near the

front face of the rim, indicating that the rim fracture was

the result of propagation of a crack that had initiated at

the focal point. This focal point is designated by an arrow

in color photographs of the rim in Figures 7(a) and 7(b)

Below the arrow there is a thermal crack which differs

in appearance from that of the other parts of the heavily

oxidized regions along the length of the tread. The thermal

crack measures about 0.98 inches along the tread (c) and

about 0.33 inches deep (a) for a c/a ratio of about 3. This

is the size and shape of the flaw believed to have existed

just prior to the rapid failure of the wheel.

The appearance of a polished and etched radial-axial

face of the rim (section 2) is shown as Figure 5, as etched

with a hot 10% HNO3 solution. No major defects were observed

on this surface, but a heat-affected zone (HAZ) of greater

than 2 inches along the tread and greater than 1/2 inch in

depth is observable. The HAZ has a shape similar to that

of the thermal crack but the HAZ is much larger. The flow

lines produced by the shaping of the wheel are visible on

the etched surface. They indicate that the wheel was

produced as a wrought (i.e. not cast) product.

Thermal checks are present, throughout the tread of

section 2, as shown in Figure 8. The tread of section 1 also

has a set of thermal checks near the fracture origin. However,

the question as to whether the thermal checks actually lead

up to and thereby initiated the thermal crack could not be

answered unambiguously from the single fracture face available

to us for this investigation.

All fillets of the wheel section were closely examined

and found to be free of fatigue cracks and of any other

indications of either extensive or abusive service.

4 . 2 Hardness Measurements

The results of Brinell hardness measurements, given in

Figure 4, indicate that, within the wear zone of the first

1-1/2 inches of rim metal, the hardness is uniformly good,

being within the range of 277 to 341 BHN specified for

Class B wheels, except for a single value of 257 BHN for the

location nearest to the front of the tread.

The values of Rockwell "C" hardness readings, as given

in Figure 6, support the findings of the Brinell measurements.

- 4 -
They further indicate that, near the front face of the tread,

there is a large softened zone around the boundary of the

heat-affected zone.

Thus, while it appears that the wheel v/as produced with

uniformly good hardness and in accordance with the hardness

specifications, the wheel has a soft zone in the region of

the HAZ boundary present on the as-macroetched surface of the

rim section.

4 . 3 Dimensional Measurements

The measured dimensions of the wheel, as given m Table

1, met the AAR specifications for wheels of design A-40,

except for the values of Ri and R2 . However, it is noted

that the measured values of R, for the wheel section on which

they were taken, do not represent the values of the whole

wheel prior to sectioning. This is so, because the act of

sectioning greatly affects these readings. It was noted by

the accident investigators that the fractured wheel contained

a crack with an opening of approximately 3/16 inches (presumably measured in the hoop direction of the tread) . The

wheel opening indicates that hoop compression, stored in the

wheel prior to the fracture event, was released by the

formation of the crack. The release of hoop compression

would be expected to increase the value of R^ and decrease

the value of R2, and our measured values for these parameters

are respectively greater than and less than the specified

values for the as-manufactured v/heel. Therefore, all

indications are that the wheel was produced in accordance

with the AAR specifications on dimensions.

4.4 Chemical Composition

The chemical composition of the sample taken from the hub

is given in Table 2. The values for carbon, manganese,

phosphorous, sulfur, and silicon, indicate that the steel met

the chemical compositional requirements of the AAR Specification M-170-69. In addition, the values given for nickel,

chromium, molybdenum, and copper, indicate that the steel is

a carbon steel grade with small amounts of these alloy

additions, and that the contents of these alloy additions are

insufficient to make the steel a low-alloy grade.

4 . 5 Metallographic ELxaminations

Careful metallographic examinations and measurements of

the maximum depth of the heat-affected zone (HAZ) on piece 2B

from section 2 indicate that the maximum HAZ depth on piece 2

- 5 -
is about 9/16 inches. This measurement, coupled with

measurements made on the macroetched surface, indicate that

the F^AZ extends along the tread for a distance of about 2

inches from the front face of the rim.

The microstructures of the unaffected base metal, of

the fine-grained region near the inside boundary of the HAZ

and of the coarse-grained HAZ region near the focal point of

the thermal crack are each shown at two magnifications in

Figures 9, 10, and 11, respectively. These microstructures

were observed on piece 2B at the locations designated C, B,

and A, respectively, in Figure 5.

We note that transformation to the structure shown in

Figure 11 (region A) requires temperatures estimated to be

as high as 1850 F. The structure shown in Figure 10 (region

B) requires about 14 00 F. Thus, the magnitude of the heat

input locally, at the front part of the tread, was large.

:4 . 6 Fractographic Examinations

In general, the SEM replicas indicated that the failure

occurred by a quasi-cleavage failure mode over the bulk of

the surface of the fracture. The results of observations of

the fracture surface near the focal point of the thermal

crack were somewhat indeterminate, but they are consistent

with the idea that the failure was preceded by the formation

of a thermal crack that was initiated at this site.

The appearances of replicas taken from locations C, D, A,

and L (Figure 3), v/ere similar, with each showing fracture by

a predominantly quasi-cleavage mode, as is shown in Figures

12 through 14. Figures 12 and 13 are considered to be

representative of the overall failure mode. Figure 12 shows

fractographs taken in location C, the geometric center of

the rim section. Figure 13 is a stereo-pair fractograph

taken at area L, in a lower part of the rim. The fracture

surface at D, the back-rim plate fillet, was similar to those

shown here. Figure 14 taken in location A near the boundary

of the heat-affected zone near (or just within) the thermal

crack shows quasi-cleavage failure with. some oxides also

being present on the surface.

The fracture mode could not be clearly established for

location A, near the focal point of the thermal crack, and

for location M, from the hub. The replicas taken from these

locations indicated the fracture face to be either highly

oxidized, or badly rubbed after the fracture event. This is

shovm in Figures 15a and 15b, respectively taken from

- 6 -
locations A and M. The parts of these surfaces that do seem

to represent actual fracture surface may even have been

disturbed by oxidation or abrasion. Nevertheless these parts

are very smooth in appearance, similar to a cleavage failure

mode

5 . DISCUSSION

Measurements of hardness, chemical composition, and

dimensions taken on the wheel section submitted to NBS indicate

that the wheel met the AAR Specification M-107-69, for wrought,

carbon steel wheels, and the requirements for Class B, rimtreated wheels of design A-4 0.

On the face of the fracture, a thermal crack v/as observed.

This crack has a focal point on the tread near the front face

of the rim. Further, it is encompassed by a heat-affected

zone (HAZ) that is larger than the apparent size of the thermal

crack. Thus, the thermal crack and the HAZ that surrounds it

are believed to have resulted from substantial local heating

of the front part of the tread.

The results of hardness measurements indicate that the

wear metal of the rim was of uniform good hardness except

for the region around the boundary of the HAZ . Thus, it is

believed that the rim was properly heat treated in production

and that the observed soft parts are the result of service

overheating of the tread near the front face of the rim.

This overheating is believed to have led to the formation of

the thermal crack and, in turn, to the crack that propagated

through the wheel causing it to. fail functionally. This

later event of propagation is believed to have occurred very

rapidly. Thus, the rapid failure of the wheel is believed

to have resulted from a thermal crack formed by overheating

of the tread in service.

The f ractographic examinations indicate that: (1) the

wheel failed by a brittle failure mode referred to as quasi

cleavage and (2) the region of the thermal crack could have

existed before the failure of the wheel.

6 . RECOMMENDATIONS

For future studies of wheel failures it is recommended

that an entire failed wheel should be submitted along with a companion wheel of the same production and service history

as the failed wheel. The material's structure and properties.

- 7 -
along with the residual stresses of the wheel are combined

to give the wheel its protection against service failure.

Thus, it is believed that, with a failed wheel and a similar unfailed wheel, further information can be developed

on both the mechanical properties of the material and the

stresses within the wheel, as they relate to questions of

fracture and of the overall suitability of the wheel for a

service application. In any event, whether or not a comparison wheel is sent, the entire failed wheel should

be sent for failure analysis whenever this is feasible.

- 8 -
Table 1

Comparison of the Dimensions Specified by AAR

and the Measured Values Taken from the Failed

Wheel

See Appendix B

for letter code

AAR

Specified

Design A-40

(Inches)

NBS

Measured

A J - o

(1) ^ B ' -o _L1 6/32 \J / -J ^ C ¥^16 NA

D -O' NA

Q 2 15/32 ^-'-^ L 50 5 19/32

N, 1 Mm. 1 3/8

Nz 1 13/16

0, \oz-o . 14 1/8 ^2)

Oz 14 3/8

P 6 7/16

Ri 5 1/16

Hz 1 7/16

Max

Finish

Bore

Assumed value

of bore

Mm

Hub

Wall i|

1 1 13/16 & 1 3/4

(1) Attributed to normal service wear.

(2) These measurements are calculated from the assumed bore

value of 10 3/4 inches and the value of the measured

hub thickness.

(3) The values of and R2 were affected by the release of

residual stress during the fracture event and during

subsequent sectioning of the wheel. Thus the measured

values given here do not represent the values for the

wheel in service.
Table 2

Chemical Composition of the Sample Taken

from the Hub. (Percent by Weight)

Carbon (Class B)

Manganese

Phosphorus, not over

Sulfur, not over

Silicon, not less than

Nickel

Chromium

Molybdenum

Copper

AAR Specifications

M-170-69

0.57 - 0.67

0.60 - 0.85

0.05

0.05

0.15

(a)

(a)

(a)

(a)

Chemical Check

Analysis

0.67

0,71

0.011

0.025

0.21

0.06

0.09

less than 0.05

0.13

(a) Not specified.
Figure 1. Radial-Circumferential Section of the

Fractured Wheel, As Received at NBS

Mag. X 1/2
Figure 2. Fractured Wheel Section Showing the Three

Parts Into Which It Was Saw Cut.

Section 1 was used for macroscopic and

microscopic examinations of the fracture.

Section 2 was used for hardness and

heat-affected zone measurements, macroscopic and microscopic examination; and

Section 3 was used for chemical analyses.

Mag. < X 1/2


Figure 3. Locations of Replicas, A Through M,

Taken on the Fracture Face.

Chemistry sample was saw cut from

section 3. Mag. X 1/2

liMvitr A. Schomatic Ropr^'sentat ion of the Location

of Brineli Hardness Impressions and

Equivalent Rockwell C Values (in

l>aronthesi s) . Mag. X 1

Figure 5. Photograph of Section 2 Showing the Brinell

and Rockwell C Hardness Impressions, the

Etched Sample, and the Saw Cut Between

Pieces 2A and 2B.

Regions A, B, and C were used for photomicrographs of the structures observed in

the rim. Mag. X 1

HEAT-AFFECTED

ZONE

28.0

25.0

23.5

27.0

28.0

34.0

28.5

25.0

23.5

21.0

27.0

28.5

30.0

27.5

26.0

24.5

22.0

.^20.0

25.5

27.0

3 2 . 32 . 5 2S. 6 24. 9 26. 0 .2 5 5

2 9 8

26. 2 28 D 30 5 28 0 28. 5 29 c 29 0 ,29 5

29. S 29 5 30 0 29 5

29. .30 0 29 1

29 4 28 5 29 .5 28 9

29 2 29 . 5 23 .5 27 .8 28.5 27.5 26.7

33 4 32. 7 34 . 9 34. 1 33. 2 31 7 31 1 31 5 32 8 30. 7

31 2 31 3 31 2 30 3 29 9

30 3 30 0 29 0 29 9 29 8

29 9 30 0 28 8. 28 7 28 9

30 0 29 1 29 0 28 6 28 7

29 .8 29 1 28 7 28

28 9 29 .0 29 0 .5

27 o 28 .5 29 0 28 . 6 28 .3

27 . 3 27 .9 28 .6 27 .5 23 .0 27 . 5 27 .5 27 .5

Figure 6. Results of Rockwell "C" Hardness Measurements

Taken On Section No. 2.

Locations of R impressions correspond to locations

of decimal points shown here.

(a) (b)

Figure 7. (a) Color Photograph of the Fracture Face

of the Rim, Showing the Location of

the Thermal Crack (Initiation Site)

and the Oxidized Region Near the Tread

and in the Flange. Mag. ~ X 1/3

(b) Close Up of the Thermal Crack Near the

Front Face of the Rim. Mag. - X 2/3

Thermal Checks Observed on the Tread of

Section 2 After Hot Etching in 1:1 HCl.

Mag. X 1

Photomicrographs Taken at Region C

(Figure 5) Showing the Unaffected

Base Metal of the Rim.

Specimen etched with 5% nital.

Figure 10. Photomicrographs Taken at Region B

(Figure 5) Near the Inside of the

HAZ Boundary.

Specimen etched with 5% nital.

Figure 11. Photomicrographs Taken at Region A

(Figure 5) Showing the Coarse-Grained

Heat-Affected Zone Observed Near the

Tread

Specimen etched with 5% nital.

Mag

X 1050

Mag

X 210

' Figure 12. SEM Fractographs Taken at Location C

of Figure 3, Showing the Predominately

Quasi-Cleavage Fracture Mode Observed

I in the Rim.

I

SEM Stereo-Pair Fractograph Taken at

Location L of Figure 3, Snowing the

Predominately Quasi-Cleavage Fracture

Mode Observed in the Rim. Mag. X 490

Figure 14 . SEM Fractographs Taken at Location A

of Figure 3, Showing Quasi-Cleavage

Fracture and Oxide Formations Observed

Near the Boundary of the Heat-Affected

Zone of the Rim.

Figure 15. SEM Fractographs Taken from the Thermal

! Crack Region (15a) and from the Hub

; Region (15b), Showing Oxide Formations,

Abraided Parts, and Flat Fracture.

I

APPENDICES
APPENDIX A

(Specification)

AAR-M-107-69
AssocLatujn oi Americaa Pwiiiroads ASSOCIATION OF AMERICAN RAILROADS

OPERATIONS AND MAINTENANCE DEPARTMENT

MECHANICAL DIVISION

SPECIFICATIONS

M-107-69

WHEELS, WROUGHT CARBON STEEL

Adopted, 1962, to Sctpbrsede Previous Stand.vsd Specifications for

0.\e-Weah and Mitltiple-Wear Wheels; Revised, 1963, 1964, 1965, 1966, 1967, 1969

1. Scope.—(a) These specifications cover one-wear, two-wear and multiple-wear wrought carbon steel wbeela for locomotives and cars—Class U,

untreated, and ciaaeea A, B and C heat treated wheels.

(b) The service for which the varioiis clasees are intended generally is as

follows:

Class U —General service where an untreated wheel is satisfactory. Class A —High speed service with severe braking conditions, but with moderate wheel loads. Class B —High speed service with severe braking conditions and heavier wheel loads. Claia C —(I) Service with light braking conditions and high wheel

loads.

(2) Service with heavier braking conditions where off-tread brakes are employed.

2. Design.—Standard and temporary standard designs and tread and

flange contours for wrought steel wheels shall be as shown in Section G —

Wheels in the A.A.R. Manual of Standards and Recommended Practices. .Ap- plication for approval of designs not shown in Section G shall be addressed

to the Secretary of the Mecbankal Divisien, A-AJEl., for sufamissioQ to the Committee on Wheels and Alias. ^

MjururACTUBB

• 3. . Process-—The steel shall be made by any of the following processes: Open hearth, electric furnace-, or basic oxygen'process.*

" •Ba«ic- o.xygen process i» defined as the steelmaking process in which

molten iron is refined to steel under a basic slag in a cylindrical furnace lined with basic refractories, by directing a jet of hijth-pority gaseous oxygen onto

the surface of the hot metal bath.

4. Discard.—A sufficient discard shall be made from each ingot to insure freedom from piping and undue segregation.

5. Temperatures.—During the manufacture, necessary care in the regulation of temperature gradients shall be exercised to obtain the physical

pnportips to be expected from the chemical composition and mechanical work

and io prevent the development of faulty structure* All wheels immediately

after the last hot fabricating operation (coning or dishing), shall be allowed to cool to a temperature below the critical range. The cooling shall be controlled

to prevent injury by too rapid coeiing below the critic^ raawse.
AssocLatioa of Ameriom Railroads

6. Heat Treataneat.—(a) For claasea A, B and C wheels, the heat

treatment ah&il coosiat of treatment of either the rim only or of the entire wheel, unless purchaser's order iadicafcea preference.

(b) Rim Quenching Treatment.—The wheelb shall be imifonuiy reheated

to the proper temperature to refine the grain and then the rima shall be

quenched. Following quenching, the wheels ^lall be charged into a furnace

for tempering to meet the requirements of Section ^, and subsequently cooled under controlled conditions.

(c) Entire Wheel Quenching Treatment.—The wheeb shall be uniformly

reheated to the proper temperature to refine the grain and then shall be

totally immersed in a quenching medium. Following quenching, the wheels

shall be charged into a furnace for tempering to meet the reqijirementj of Section 9, and subsequently cooled under controlled conditions. ChBMICAL RSQUmCMENTS

7. Ladle Aiial78t&,—(a) The steel shall conform to the following chemical requirements: Per Cent

[ Class U 0 . 65—0 . 80

I Class .\, not over 0 . 57 Carbon

I Class B _ 0.57—0.67

Class C 0.67—0.77

Manganese 0 . 60—0 . 85 Phosphorus, not over _ 0.05

Sulfur, not over .. 0.05

' Silicon, not less than _ 0.15

(b) An analysis of each heat of steel shall be made by the manufacturer to determine the percentage of the elements specified in Section 7. This analysis

shall be made on a test specimen taken during chfe pouring, of the heat. The

chemical composition thus determined, together with such identifying records

as may be desired, shall be reported to the purchaaer or his representative, and

shall conform to the requirements 3p)ecified in Section 7.

8. Check Analysis.An analysis may be made by the purchaser from a

wheel block or from a finished wheel selected from each heat by the purchaser's

representative. The chemical composition thus determined shall conform to

the requirements specified in Section 7, with a pennissible carbon variation of minus 0.02 or plua 0.03 percentage points. Samples from wheel bkscks shall be drilled from the end of the block midway between the center and outside. When a fikoiahed wheel is uaed, the sample ^lall be obtained from the rim face or the hub in a m&nner which will not impair the usefulness of the wheel. No drilling of the finished wheel plate shall be permitted. E^ch sample from any one block or wheel ahall be thoroughly mixed together and shall be clean, and free from scale, oH and other foreign substances. PBTSICAt. REQUntEUENTS

9. Biinell Hardaesa.—(a) The hardness of the rim, when measured in accordance with the requirements of Section 9 (b) shall show the following

values: Mirmmim Maximum

Gasa Hardness Hardness

A 255 BHN 321 BHN

B 277 BHN 341 BHN

C 321 BHN 3'^3 BHN

(b) Method of Measurement.—Measiirement shall be made on the front

face of the rim with the edge of the impression not leas than inch from the

racliaa joiiuzig faee and tread. Before making the impresMon, any decarbur-
Association of .\merican Railroads

i^ed metal shall be removed from the front face of the rim at the point chosen

for measurement. The surfice of the wheel rim ^lail be properly prepared to permit accurate determination of hardntsa.

(c) Hub Hardness.—When so ^jecified in order to facilitate machining,

the maximum hardness on hub face of wheels which are entirely quenched

shall not exceed 293 BHN at any point not more than y> inch frorc? bore.

10. Number of Teats-—(a) Where continuous heat treating furnaces

are used, Brinell hardneae measurementa rioail be made on 10 per cent of the wheels from each heat. Where batch t^pe heat treating furnaces are used,

Brinell hardness measurements shall be made on 10 per cent of the wheels from each heat treatment lot, provided that at lea^i, one (1) wheel is selected

for test from each heat represented in the beat treatment lot. For either

process, when there are less than twenty (20) -wheek from a heat, a minimum

of two (2) wheels shall be checked for hardness except -s^iien there is only one

(1) wheel from a heat, in which case a BrineU hardness measurement shall be made on the one wheel.

(b) If all the wheels tested n^t the requirements of Section 9, ail of the wheels represented shall be accepted.

(c) If any wheel tested fails to meet the requirements of Section 9, it shall be checked by making two (2) additional hardness measurements, one on

each side of the point first measured and each approximately 1 inch from that

point. If both of these check measiuements meet the requirements of Section 9, the wheel shall be considered to have met the requirements of Section 9. (d) When continuous heat treating furnaces are used, should any of the wheels tested fail on check test to meet the requirements of Section 9^ the manufacturer may test for individual hardness mea.surement^ all of the wheels of that heat in the lot submitted for inspection and those meeting the require- ments of Section ;I shall be accepted. Where batch heat treating furnaces arc

used, should any of the wheels tested fail on check test to meet the require- ments of Section.*?, the manufacturer may test aU of the wheels in the heat treatment lot for individual hardness measurement and those meeting the requirements of Section fi^ shall be accepted.

1 1. Retre*tm.ent-—Any wheel failing to meet the reqiurementa of Section

9, may be retreated and tested in accordance with Section 10. Mating

12. Mating.—Wheels shall be measured and marked to one-half tape Buxs and shipped in pairs of the aune measured tape size.

PiDUnSSIBLS VaMATTONS DC DntEXSIONS

13. Gages*—The gages and tape* shall eooiorm to and be used as re- quired by the Staodards «f tiw Mecbanical Divis^ A^aoeiatioD of American

Raiiroada.

14. PennisaiWe Yaruttions.—(a) The wheels diall conform to the dimenmona with tolerances aa specified in Section G—Wheels.in the .A.A.R. -Manual of Standards and Recommended Practices. (b) Where the individual design sheets allow a certain per cent of the wheels to vary from standard dimensions for tape size by a given amount,

the percentage of such wheels shipped by any manufacturer shall not

e-xceed this per cent during a calendar year. No individual purchaser may

receive more than this per cent of his daily shipments of such wheels

except by ag^reement with the mannfaanrer.

A—197D
Finish

15. Finish.—(a) Wheeb ah&ll be rough bored and shall not have black

spots in the rough bore. Front hub face of wheels (1-W, 2-W and MW) shall be parallel to the plane of the vertical reference line and may be smooth forged

or machined. The back hub face may be smooth forged or machined.

(b) The contour of tread and flange shall be aa shown in the A.A.R. Manual of Standards and Recommended Practices and shall be machined and

hniahed smooth without excessive tool chatters.

fc) Wheels shall be° given a thorough surface examination and gaging at the place of manufacture before being offered for inspection. They shsU have

a workmanlike finish and must be free from defects liable to develop in or cau^e removal from service. "As forged" surfaces shall be free of abrupt

ohaiigea in section or grooves and m a clean condition free of scale prior to

final inspection. Where corrective machining or grinding has been employed

such surfaces shall not exceed a roughness of 500 microLnches, and a uniform

transition from the machined or ground surface into the plane of the "as forged" surface must be provided.

(d) Wheels ahull not be covered with any substance to such an extent aa

to hide defects.

(e) Supplementary requirement S-1 shall only apply when the removal

of mill scale from the wheel is to be done by the manufacturer. Ma-EKUNG

16. Marking.—(a) Identification markings shall be legibly hot stamped on the back rim face as shown in Fig. 1. When the original hot stamping on wheels for freight service is removed it shall be cold stamped

on rhe back hub face as shown in Fig. 2. Repairs to illegible hot stamped

characters may be made by cold stamping. Passenger car and locomotive wheels may be hot or cold stamped on the back rim face. At the option of

the purchaser locomotive wheels may be cold stamped on the front hub as shown in Fig. 2.

(b) The tape size of all wheels shall be stencilled on back plates with

chrome yellow paint in characters at least one inch high.

A— 1P70
AssociadoQ ot American Railroads

. 5 IxSPECnON A.\D Re/ECTIO-N'

17. Inspection.—(st) The inspector representing the purchaser shall have

free entry, at all times while the work on the contract of the purchaser is being

performed, to all parts of the manufacturer's works which coQcern the manufacture of wheels ordered. The manufacturer shall afford the inspector, free of charKe, all reasonable facilities and necessary assistance to satisfy him that the wheels are being furnished in accordance with these si)ecifi.cation3. Defects not

readily visible to the unaided eye are usually detected by ultrasonic testing.

Such test shall be used in the manufacture of all wheels as a part of mill quality

control proce<lure3. Testa and inspection siiall be made at place of manufacture pnor to shipment, unless otherwise specified.

(b) The purchaser may make testa to govern the acceptance or rejection of the wheels in hia own laboratory or elsewhere. Such tests ahaii be made at

the expense of the purchaser.

(c) .\11 tests and in^>ecti(»i shall be so conducted as not to interfere ud>

necessarily with the operation of the works.

18. Rej«ctioii.—(a) Wheels represented by samples which fail to conform

to the reqiiirements of these specifications will be rejected.

(b) Wheels which show injurious defects subsequent to original in- spection and acceptance at the manufacturer's works, or elsewhere, will be

rejected, and the manufacturer shall be notified.

19. Rehearing.—Samples tested in accordance with this specification,

which represent rejected wheels, shall be held for a period of fourteen (14) days

from date of the test report. In case of di^tisiaction with the results of the

tests, the manufacturer may make claim for a rehearing within that time.

SupplementAJiT REQumzstENTs

The following supplementary requirements shall apply only when specified

by the purchaser. Details shall be agreed upon by the manufacturer and the purchaser. SI—Wheels for use under locomotives other than steam shall have all mill scale removed from the entire whe^ f^ior to final inspection.

A—1970
M-1B7-A9

e

Aseociatioa of Americ&n Railroads

MARKING OF WROUGHT STEEL WHEELS—RIM STAAIPING

Note I. Stamping to consist of date of mamifacture. brand of ir%nufAcX.ursr , majiufacturer 's serial number, class and type of heat treatinent if neat treated and design designation. Stanoing on locomotive jiheels is limited to 13 characters and

the design designation shall be stencilled on the tack plate •itn chro>e yellow

paint with characters at least two inches in height. Note 3. Stanpings to be spaced a ninioun of one inch betwean characters arid two inches between groups, located not less than 1/9 inch fron inner edge of r ira. On locomotive wheels the stamping shall be located not less than I/4 inch frcm

the inner edge of the rim. Note 3. Brand limited to one initial: i-Armco; B-fleth lehera; C-Carnegie (Pittsourgh Plant); E-Edgewater; G-lllinois (Gary Plant); J-Suni tomo Metal Industries; P-Steel , Peech

and Tozer; S-Standard; T-Taylor Bros, and Co.. Ltd.; Z-Canadlan Stael itheel , Ltd. Note U. Dies used to prodijcft characters shall be '/j inch nominal height at crest and

hot stamping siwl I be ncnina'ly Vjj inch in depth. Italicized characters

(sloped upward to right), shall be used. Note 5. Class markings as follow€: A - Class A, riiw treated AE - Class A, entire wheel treated

B - Class 8, r im treated

BE - Class a, entire wheel treated

C - Class C, rini treated

CE - Class C, entire viieel treated Untreated wheels (Class U) are not nwked for claaa.

A—1970
Aoxuciktion of Ainefic*n Rjilroaxi"

ALTERNATE MAEIKING OF WROUGHT STEEL WHEELSHUB STAilPLNG

Class

Note I. L-<:tnotiv» •n»»is ar« stamceo on t.ie front "ace and wheels for freight serv'ce ar* -tamoeti on tne tack nuo face.

Nc'.e 2. Stimpiig to consist of oate of Tan^jfacture. rrand of r^nufac'-urer , -ranu- fa^:ur-?r's atrial numoer, ciasi aria tyoe of "ea; t.'»atr»nt if neat treated and desi-jn cesicnation. Stawoinq on locoocti^- ^^eis is limited to 13

C.'iaracte<"s ano tne design aesiqnation s.iail stencil Iwd on tlie bacn piatt

• itn cnrome jrellcw paint with a»ar»cters at liast Vwo Inches in height.

» c

' Hot* 3. Stampingj to be sc»ced aooro» iTM te I y '/j incn bexieen characters and at)oro«- iTMtel)r l''2 inches between groups and located jporamrately central of the hub face.

(tete U. Steel sta»o« uaed to produc* c*»«-icter» shall wt be less than '"ch in height. Note 5. Class ou-ktngs M falloM:

A - Claas *, rim trtated

*£ - Class i, entire woeel treated

3 - Clisa 3. rin treated

3c - Cla&s 3, entire wneei treated C - Clasc C. rim treated C£ - Clua C, entire meal treated Untreated aheels (Class U) are not HH-lvd fw class.

APPENDIX B

(Specification)

AAR Dimeh^sions for Steel Wheel of

Design A-40 and Perinissible Variations in Dimensions not shown by

Tolerances on Individual Design

Sheets.

«

Association of Axnerican Railroads Wbcef

Vealsca

STEEL WHEEL A-40

Standard

Adopted, 1946

Topioq

/\

i Is

-5^

0.

standard 40 Diesel Locomotivg Whcc}

Notes

See page G—27 for permissible variations in dimensions not shown by above tolerances.

IDimQnsion:

Tblcrancc'S

A

B

. '7 -4. x. 1 ijC-q,

i

1 1

1 G

L 02, ^'

.N,

Hz

0,

P

Ri

Hz

) 11 j; J Mqx . Finish

Bore sU.T j Mm

Hub

Wall

1

G—67—Aug. 1, 1946

l!
Association of American Railroads

PERMISSIBLE VARUTIONS IN DIMENSIONS NOT SHOWN

BY TOLERANCES ON INDIVIDUAL DESIGN SHEETS

1. Inside Diameter—Back Face of Rim.—The inside diameter of the rim at the baclt face of the wheel shall not vary more than ?4 in. under the nominal dimension. The maximum diameter at this location is governed by

the rim thickness and the tape size.

2. Inside Diameter—Front Face of Rim. —For narrow flanKo wheels, the in.side diameter of the rim at the front face of the wheel shall not exceed

that at the back face of the wheel and shall not vary under this dimension

by more than H in. For wide flange wheels, the inside diameter of the rim

at the front fare of the wheel shall not differ from that at the back face of the wheel by more than H in.

3. Thickness of Rim.—In any wheel the radial thickness of the rim

shall not vary more than j « in. around the wheel.

4. Comer at Inside Diameter of Back Face. —A sharp corner is preferable

to facilitate measurement. In any case the radius of the corner shall not exceed

3^ in.

5. Plane of Back Face. —When wheels are gaged with a straight edge

applied to back faci' of rim, no point on back face of narrow flange wheels more than 1}^ in. from inside edge of rim shall be rriore than 1^ in. from the

straight edge. For wide flange wheels, no point on back face of rim shall bo more than l{i in. from siraight edge.

6. Hub Wall Thickness.—The thickness of the hub wall in any one wheel

raeaaured at any two points equidistant from the face of the hub shall not vary by more than 3,^ in. if the hub is not machined, nor by more than 3^ in,

if the hub is machined.

7. Rotundity.—Tread when gaged with a ring gage must not have

opening between tread and gage at any point over 'n.

8. Diameter of Bore.—The diameter of rough bore shall not vary more

than '/fs in. over, nor more than j'si in. under the dimensions specified. The

8peci6ed rough bore .shall be at least ^4 in. less in diameter than the finished bore, subject to \{s in. tolerance and/or 1^ in- under the diameter specified.

9. Eccentricity Bore. —Eccentricity between the rough bore and tread measured in tiic plane of the taping Imc shall not exrpecl ' m. NOTE.—Where dimension R| and Ri is marked f. extra ptork of '<« to '15 inches over

specified dimension may be left for machmiiiK of each finished surface or wheel may be furnished

fioiabed to eiact dimenaioa abown. iiub length tolerance is based on finished dimensioa.

G-27—1970
NBS-lUA (HEV.

U.S. OfcCt^T. OF CC'I.M. BIBLIOGRAPHIC DATA

SHEF.T

1. I'lHI.K A TION OK Kl IT'K l' XD. NBSIR 74-4722. oov't Acc< s.siim No.

3. Kcc ipit ni '.s Accession N.j.

4, 1 I 1 1 . 1- Aa I

' M r 1 1 1 1 . 1

ANALYSIS OF RAILROAD VfflEEL FAILURE - DERAILJ^IENT

AT RICHMOND HILL, NEW YORK, MARCH 10, 1973.

5. I'uhl iL .It ion D.itr April 1974

6* t^c r f or ni 1 n ^ Or^iin ( /iit lon

7. AL' I HORi S1 C. G. Interrante and G. E. Hicho

8. Pcrfi^rniirm Uru.iii. Ki i~>ort No. NBSIR 74-472

9. P1-.RF0H.MIM; i)Ko.\.\1/..\ i u>n x^.Mi-: .ano .mm^ki

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

10. Pro|L c t, las;. Aork 1 nit .\>>. 3120413

11. Contract Cirant No.

12. Sponsoring Oriz.inization Name anJ Complett.- AJJrcs.s (Street, City. State, ZIP)

Federal Railroad Administration

Department of Transportation

Washington, D. C. 20590

13. Type of Report HiTuvi Covered pallure I Analysis Report

14. Sponsorinj; .Agency l.-ode

15. SL'PPLESU-NTARV NOTH.s

16. .AriSlR.AC 1 (A 200-nord or !ess factual summary oi most ;iigfii{icant information. If document includes a significant

bibliography or literature survey, mention it here.) At the request of the Standards and Procedures Division, Federal

Railroad Administration, Department of Transportation, a failure analysisj

was made of a section of a railroad v/heel which had reportedly failed in j service and had led to a derailment at Richmond Hill, New York. A

section of the failed wheel was sent to NBS where it was examined and i measurements made to determine the cause of the failure and to determine j whether or not the wheel had been produced in accordance with applicable i specifications

The chemical comtposition , hardness, and dimensions of the wheel

section were measured. The results indicate that the wheel m.et tihe requirements of the specifications. These measurements and other obser- vations indicate that the failure occurred as a result of local over- I heating at the front of the tread. It is believed that this overheating j occurred in service and resulted in the formation of a thermal crack in I this region. This crack subsequently propagated rapidly in a radial direction through to the hub of the wheel.

17. KEY \tORDS (six to tuelve entries: alphabetical order; capitalize only the first letter of the first key word unless a proper name: separated by semicolons ) .. Chemical composition; failure analysis; fracture characteristics;

hardness, railroad wheel.

18. AVAILABILITY [_ Unlimited

For Official Distribution. Do Not Release to NTIS

r" Order From Sup. of Doc, U.S. Croverntnent Printing Office

Vl a.shington, D.C. 20-10:, SO Cat. No. Cl ^ r 9''^.'^'' '''''"'^^ National Technical Information Service (NTIS)

Sprini:.ficU. Vir,k;inia 22I'il

19. SECURITY CLASS

(THIS REPORT)

L'NCL ASSIFIED

20. SECURITY CLASS

(THIS PAGE)

UNCLASSIFIED

21. NO. OF P.\GES

4 2

22. Price

USCOMM-OC 29042-P74
1 rrdisi'.-:!