KSKSKSKS KSKSKSK KSKSKS KSKSK KSKS KSK KS

KSKSKSKSKSKSKSK KSKSKS KSKSK KSKS KSK KS

KS R 9221

Wheels for railway rolling stockKS R 9221:2008

Translated and Published by Korean Standards Association

http:// www. kssn.net

○C KSA 2011 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any

means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher

Translation without guarantee In the event of any doubt arising, the original standard in

korean is to be evidence

2012-02-27, 한국철도공사에 라이센스를 부여하며 불법 복사 및 무단 배포를 금합니다.

KOREAN INDUSTRIAL STANDARD

KS R 9221:2008

Wheels for railway rolling stock

1 Scope

This Korean standard specifies carbon steel rolled wheels (hereinafter, referred to as wheels) used for

railway rolling stock with the maximum speed of below 150 km/h.

2 Normative References

The following referenced documents contain provision which, through reference in this text,

constitute provisions of this standard. These normative references apply the latest version.

KS B 0801, Test pieces for tensile test for metallic materials

KS B 0802, Method of tensile test for metallic materials

KS B 0805, Method of brinell hardness test

KS B 0809, Impact test pieces for metallic materials

KS B 0810, Method of impact test for metallic materials

KS B 0817, General rule of ultrasonic testing of metals by the pulse echo technique

KS D 1801, General rules for chemical analysis of iron and steel

KS D 1802, Methods for determination of phosphorus and iron and steel

KS D 1803, Methods for determination of sulfur in iron and steel

KS D 1804, Determination of carbon in iron and steel

KS D 1805, Determination of silicon in iron and steel

KS D 1806, Methods for determination of manganese in iron and steel

3 Terms and definition

For the purposes of this document, the following terms and definitions apply.

3.1

Wheel contact surface

abrasion areas of a cylinder part of wheels which come in contact with railways


KS R 9221:2008

2

3.2

Rim

edge portion of wheels including the surface which comes in contact with railways

3.3

Boss

part of wheels where axles are pressured

3.4

Plate

circular plate which connects the rim with the boss

4 Types

As shown in Table 1, type of wheels is categorized by use.

Table 1 ― Types of wheels

Symbol Use Note

RSW1 Rolling stock Quenching or tempering for rim

RSW2 Electric locomotive or electric rail car Quenching or tempering for rim

RSW3 Diesel locomotive or diesel rail car Quenching or tempering for rim

5 Requirements

a) Wheels must be consistent in quality, and there must be no marks, scratches, exfoliation, pulling

and other defects under a normal condition.

b) Wheels are manufactured by steel which is dissolved by using Basic oxygen furnace, Open-hearth

furnace or Electric furnace. Deacidification process is performed on the steel in the furnace and

ladle and the steel is made by casting method or continuous casting method. When the casting

method is used, it should be made by lower casting.

c) Wheels are forged and then formed by rolling. The rim part must be heat-treated i.e. quenching

or tempering.

d) Wheel shapes (Figure 1) follow an authorized manufacturing drawing. Unless there is mutual

agreement between parties concerned, wheel shapes must meet the rules suggested by the below

Tables 2 and 3. If there are sectional marks on plate parts as well as around the section R of the

boss, the depth must be within 10 percent of the cylinder thickness.


KS R 9221:2008

3

Figure 1 ― Shapes of a wheel

Table 2 ― Allowable values of dimensions

unit: mm

Allowable values of dimensions

Classification

Plate

thickness

t1, t2

Rim

thickness

T

Inner

diameter

of Rim

d1

Outer

diameter

of Boss

D1, D2

Boss

thickness

T1, T2

Inner

diameter

of Boss

d

Height

of plate

parts

l

Central

distance

of cross

section

of Plate

E

Without

finishing

+6

0

3 or

below

-0

-12

+15

0

10 or

below

-4

-6 ±6.5 ±3

Wheels

with

finishing

process

for

section R

With

finishing

+6

0

3 or

below

-0

-12

+15

0

10 or

below - ±6.5 ±3

Without

finishing

+8

0

3 or

below

-0

-12

+25

0

10 or

below

-4

-8 ±8.5 ±5

Wheels

without

finishing

process

for

section R

With

finishing

+6

0

3 or

below

-0

-12

+25

0

10 or

below - ±8.5 ±5


KS R 9221:2008

4

Table 3 ― Allowable values of dimensions for rim

unit: mm

Allowable values of dimensions

Location of rim Classification

C K

Outer diameter of rim

D

Without finishing

process

-1

-3

+3

+0

+8

-2

With finishing

process -

+3

+0

+5

-2

6 Inspection and test methods

6.1 Types of inspection and methods

The whole manufactured products are tested by the following items and determined when must pass

each test.

a) Appearance inspection In accordance with an authorized manufacturing drawing, there must be

no marks, polluted damage, exfoliation and other defects found through inspectors’ eyes.

b) Dimension inspection Dimensions of each part must be inspected to check if they are

consistent with the manufacturing drawing.

6.2 Types of inspections and methods

a) Ultrasonic test is done for the whole manufacture product, whereas a chemical analysis test,

tensile strength, hardness or impact test is done in type checking.

b) For the chemical analysis test or mechanical quality test, one wheel from each steel furnace is

chosen from which test pieces are extracted. If all test pieces are considered fine, respective steel

products can be used.

6.2.1 Chemical analysis test

Chemical analysis test of wheels are presented in Table 4 in accordance with KS D 1801, KS D 1802,

KS D 1803, KS D 1804, KS D 1805, KS D 1806.


KS R 9221:2008

5

Table 4 ― chemical compositions of wheels

unit :%

composition C Mn Si P S Cu

Content 0.67 or below 0.6 ~ 0.9 0.15 or above 0.045 or below 0.045 or below 0.35 or below

6.2.2 Test for mechanical qualities

a) Tensile strength, hardness, impact test pieces are extracted from the rim part of wheels. With

hardness test pieces being in a cross section form as shown in Figure 2, hardness of each wheel

must be above the minimum values at the depth of 25 mm from the wheel contact point.

Hardness test is based on KS B 0805, while tensile strength or impact test pieces are extracted

from the marked areas shown in Figure 3 and 4.

unit: mm

Figure 2 ― Hardness test piece

unit: mm

Figure 3 ― Location of extracting tensile strength test piece


KS R 9221:2008

6

unit: mm

Figure 4 ― Location of extracting impact test piece

b) The sample of KS B 0801 Issue 4 is used for tensile strength test of wheels in accordance with KS

B 0802.

c) The sample of a) U notch in Figure 2 of KS B 0809 is tested three times in accordance with KS B

0810.

d) Mechanical qualities of wheels must be within the figures of the below Table 5. The minimum

limits of strain and cross-section contraction rate are the lower limit of tensile strength and the

upper limit of tensile strength respectively. Strain or cross-section contraction rate for the mid-

range tensile strength is calculated through a rule-of -three sum.

Table 5 ― Mechanical qualities by type of wheels

Tensile strength test Hardness test Charpy impact

test

Symbol Tensile

strength

(N/mm2)

Strain

(%)

Cross-section

contraction rate

(%)

Hardness

(HB)

Absorption

energy

(J)

RSW1 835~960 14 (min)

11 (min)

28 (min)

23 (min) 248~285 20 or above

RSW2 930~1030 13 (min)

10 (min)

26 (min)

20 (min) 269~311 20 or above

RSW3 980~1130 11 (min)

8 (min)

22 (min)

16 (min) 294~341 20 or above


KS R 9221:2008

7

6.2.3 Ultrasonic test

Ultrasonic tester must have a frequency range of 2 to 5MHz. In accordance with KS B 0817, the

inspection is done after heat-treatment to check if there are internal discontinuous structures of all

rim parts of wheels. There must not be echoes due to internal defects.

6.3 Retest

Although there are some faulty mechanical qualities found, a retest can be done by using extracted

two blank materials. If one of the two fails to meet the standards again, the whole product in the

steel furnace can be annealed and re-heat treated for one more test. However, in this case, tensile

strength, hardness and mechanical qualities test are done for two wheels.

7 Marking and packaging

7.1 Marking

The following contents must be stamped in an easily-noticed place. The method of stamping (cold or

hot) and its location are subject to the agreement between parties concerned.

a) Manufacturing date (month / year)

b) Name of manufacturer

c) Number of steel furnace

7.2 Packaging

Finished products must be suited for transportation and storing.

－end－


Korean Standards Association http://www.ksa.or.kr

KS R 9221:2008

KSKSKS SKSKS KSKS SKS KS SKS KSKS SKSKS KSKSKS

Wheels for railway rolling stock ICS 45.060


KSKSKSKS KSKSKSK KSKSKS KSKSK KSKS KSK KS

Documents

Transcript of KSKSKSKS KSKSKSK KSKSKS KSKSK KSKS KSK KS