BY

TETSUYA OOMORI*

SYNOPSIS:

27 years ago, we started manufacturing NS Hyper Beam® at Wakayama Work (Sakai Area)

of Nippon Steel & Sumitomo Metal Corp. To achieve production of NS Hyper Beam, We

have established innovative technology, “Flexible universal rolling technology”

In the manufacture of conventional H-beam, inside web height and flange depth cannot be

controlled because of technical constraints. Therefore synchronous change of beam depth and

width with its thickness is inevitable in a same size series. We’ve broken through constraints

with flexible rolling technology.

This technology includes 3 innovatory technical elements.

1. The skewed rolling mill and the free size finishing mill for flexible rolling inside web

height.

2. The free size edging mill for flexible rolling flange depth.

3. The free size roller straightening machine that has variable barrel length rolls.

The development of this flexible rolling technology has enabled us to manufacture uniform

depth and width in a same size series. In addition, it has opened possibility of manufacturing

a multi-size series, using only one set of rolls.

We are manufacturing 611 sizes NS Hyper Beam® and other cross section which

corresponding JIS, ASTM and EN H-beams standards.

Furthermore, we have been producing Hyper Beam VE® (Value Ecology & Economy) series

NSYP®345B (+20MPa yield stress), and H-beam which improve low temperature properties

for onshore and offshore plant fields (CVN spec -40°C >27J).

Keywords: H-beam, Hyper Beam®, universal mill, edging roll, skewed rolling mill,

finishing mill, roller straightening, NSYP®345, low temperature properties

* Technical Staff of Large Shape Mill, Shape Div, Wakayama Works (Sakai Area), Nippon

Steel and Sumitomo Metal Corporation, Japan

FLEXIBLE UNIVERSAL ROLLING TECHNOLOGY OF H-BEAM

AND PRODUCT DEVELOPMENT

1. Introduction

Nippon Steel and Sumitomo Metal Corp. (NSSMC) Sakai Large Shape Mill started its

operation in October 1961 as a first large section mill in Japan employing universal mills.

Since then, a series of equipment renewals and remodeling as well as constant technical

development and quality improvement, we have succeeded in producing extra-thick

H-beam in 1967 as well as a large variety of high quality products such as H-beam, Steel

Sheet pile, and Unequal-sided angle. We have also produced and marketed: structural

H-beam, NSHYPER BEAMTM

, with incremental depth and width of 50mm pitch; and

other innovative products that span the history of construction in Japan. Working

together with end users, we have also endeavored to spread the use of steel structures in

building construction and promoted the use of structural H-beam as well as developed

key technologies in design, fabrication and construction fields.

In this paper, the name of each part of the H-beam is defined as shown in Fig.1

Fig.1 The name definition of H-beam section

1.1 Introduction of NSHYPER BEAM

In the field of H-beam, with use of the epoch-making process, we commenced in

November 1989 the manufacture and marketing of innovative H-beam NSHYPER

BEAM, externally constant H-beam.

NSHYPER BEAM has several user-friendly characteristics at its cross-section.

First of all, NSHYPER BEAM is rolled H-beam to be replaced Built-up H-beam. This

feature means advantages on saving labor force and fabrication term as well as higher

quality due to elimination of welding operations.

Second, as shown in Fig.2, NSHYPER BEAM has uniform-outer-dimension, different

from conventional H-beam shown in Fig.3, the uniform-outer-dimension has the same

outside web height and flange width within a same size-series, regardless of the flange

and web thickness.

Third, there are many choices of series and sizes with NSHYPER BEAM.

For example, the depth and width of NSHYPER BEAM increase depth and width by

50mm (app. 2 inch) pitch. Furthermore, wider size availabilities are realized, the number

of availability is 47 series and 611 sizes (Regular sizes: 42 series, 328sizes, Available

sizes: 5 series, 283 sizes).

Outside web height

Inside web height

Flange depth

Web thickness

Flange thickness

Fla

nge w

idth

Web-flange cornerCenter ofoutside flange

For these reason, NSHYPER BEAM can help structural design optimize for less steel

weight and better cost performance.

2. Production Process of NSHYPER BEAM

2.1 Conventional manufacturing process of H-beam

In the general, as shown in Fig.4, universal rolling method is adopted in the conventional

H-beam manufacturing process.

Fig. 4 Conventional manufacturing process of rolling H-beam

Technical constraint of conventional manufacturing process is that the inside

web height and the flange depth are varied in the same size series, Because of

the determination of roll-profile, such as the flange depth defined by depth of

the edging roll, the inside web height defined by barrel length of the

horizontal roll. As the result, the flange depth and the inside web height

cannot be changed with same roll profile in conventional process. In order to

breakthrough this technical constraint, horizontal rolls in universal mills and

edger rolls have to be exchanged according to a product dimensions.

Therefore, we had to prepare many variety of roll profile, and exchange roll

frequently to be decided according to dimension of Rolling H-beam. For these

reasons, productivity and manufacturing cost became worse.

uniform

uniform different

different

Fig. 2 Uniform-outer-dimension H-beam Fig. 3 Conventional H-beam

2.2 Flexible universal rolling process

These constrains of conventional manufacturing process have been resolved by

introducing our new rolling technology. As shown in Fig.5, the new manufacturing

process of H-beam is composed new technology including four special equipments.

Fig.5 New manufacturing process for NSHYPER BEAM

2.2.1 Free-size edging roll

Free size edging roll was developed for flexible flange-depth rolling.

The caliber depth of the conventional edging roll is constant, so the flange depth of the

H-beam is restricted by roll dimension. Whereas, the free size edging roll has variable

adjustment mechanism of caliber depth, to fit in the flange depth of rolling H-beam size

dimension. (Fig.6)

Fig. 6 Free size edging roll

Fig.7 shows the construction of a free-size edging roll having a variable edging calibre

depth. The free-size edging roll is composed with horizontal roll, eccentric ring,

web-restraining ring roll, and web-restraining ring roll positioning device.

In the free-size edging roll, flange-edge-rolling section is separated from the

web-restricting roll section, and the two sections are linked by an eccentric ring. By

turning the eccentric sleeve using the eccentric ring for positioning use installed outside

the horizontal roll, the distance between the flange-edging-rolling position and the web

restricting ring roll top position can be changed, thereby making the calibre depth

variable.

The advantage of using the free-size edging roll is that the calibre depth of an edging roll

is maintained close to the depth of the flange of a product in any pass in rolling, and

Variable depth of caliber Skewed rolling mill Free size finishing mill Free size roller straightener

constant

Conventional edging roll Free size edging roll

a A

Variable (a ⇔A)

therefore products having improved web-center-off-ness can be manufactured as

compared to the case of using conventional edging rolls.

Fig. 7 Construction of free-size edging roll.

2.2.2 Skewed rolling mill

As methods for adjusting inside web height without changing rolls, technologies such as partial inside web rolling, inside web stretching, and width direction web rolling have been proposed. Nippon Steel and Sumitomo Metal have adopted the skewed roll type rolling method, which is capable of efficiently adjusting inside web height in a wide range with only one pass. The principle of this rolling method is shown in Fig.8, wherein the centerlines of four rolls installed on in the left, right, top, bottom positions cross the direction of rolling by an angle of a with a separation distance, L, between the left and right roll. In this rolling mill, both edges of web which are rolled thicker than center portion (additional thickness) provided in the foregoing stage are rolled in diagonal direction, thereby expanding the inside web height. In this rolling, products with required web height can be obtained by setting a and L to meet the required expanding condition of the inside web height.

The deforming behavior of a material during the roll bite in skewed roll type rolling mill is shown in Fig.9. Deforming behavior can be discussed in three separate stages. In the first stage, on the entry side of rolling, although reduction is not applied to web thickness, the roll side face contacts with the inner side of a flange and the whole of the web are elongated in the width direction, and thereby, the inside web is expanded. In the second stage, the web portion with additional thickness is rolled in the width direction and a

Fig. 8 Principle of skewed rolling

large increase in inside web height is provided. In the third stage, on the exit side, although rolling reduction of the web is finished, the roll still remains contact with the inner side of the flange and the whole of the web is stretched, and the expansion of the inside web height is achieved. As mentioned above, an increase in the inside web height in skewed roll type rolling method is brought about by stretching of the web and the flow of an extra thickness portion in the web width direction. The second area is the characteristic point in the skewed rolling mill method. In this area, the shape collapses such as ditch at the center of the outside flange and necking at the web-flange corner are prevented because reduction of δW helps metal flow toward expanding the web thickness, and the radial rolling force can be decreased because δW is reduced with stress toward expanding. Therefore, these advantages made it possible to expand over 40mm without shape collapse.

2.2.3 Free-size finishing roll

In order to finish-roll by the finishing universal rolling mill after adjusting the inside web

height to a prescribed dimension by the skewed roll rolling mill, horizontal rolls of which

barrel length have to be adjusted within a short time on line are needed, and for the

purpose, the barrel length adjustable horizontal roll as shown in Fig.10 is used.

In the construction of the barrel length adjustable horizontal roll, a highly reliable roll

barrel length adjusting mechanism is completed with a highly rigid arbor mounted by roll

chocks and with a barrel length adjusting mechanism installed outside the work side roll

chock, thus maintaining the bending rigidity of the roll shaft.

Fig. 9 Deformation activities in the roll bite

Rolls separated for barrel length adjustment are fitted to the arbor and an

intermediate sleeve respectively via interface-shrink. The intermediate sleeve

with an interface-shrink-fitted work side roll is fixed in the axial direction by

a thrust bearing built in the work side roll chock. On the other hand, the

arbor with shrink-fitted drive side roll runs through the inside of the

intermediate sleeve and is connected to the driving section of barrel-length

adjusting mechanism at its end. The work side roll is installed on a

double-structured roll shaft, and its rotational force is transmitted via a

spline. The barrel length is adjusted by changing the roll separation distance

between the left and right side rolls (inner and outer side rolls) with a screw

mechanism.

2.2.4 Free-size roller straightener

In order to straightening-roll by the multistage roll straightening machine after adjusting

the inside web height to a product dimension, horizontal rolls of which barrel length have

to be adjusted within a short time on line are needed. Furthermore, to straighten the

deformation of a product such as curvature on both up and down or left and right, angle

of flange and web, barrel length is adjusted each straightening roll independently. For the

purpose, the barrel length adjustable straightening roll as shown in Fig.11 is used.

Fig. 11 Free size roller straightener

Variable barrel length rolls

Fig. 10 Structure of free-size finishing roll

3. Current development of NSHYPER BEAM

3.1 Production technology and international size variation

Currently, as introduction of flexible universal rolling technology, constant outside-web

height H-beam of max 47 series, 611 sizes in the size range from 400 x 200 to 1000 x 400

is achievable. Furthermore, H-beam of various international standards is also produced

without changing rolls. Fig.12 shows corresponding standard and the shape, available

standards are not only JIS grade but also international standards such as ASTM, EN,

AS/NZS. For example, as shown in Fig.13, NSHYPER BEAM has comprehensive

size-series variation and cover European standards H-beam.

ASTM BS4 JIS G AS/NZS

A6 3192 3679.1

✓ ✓ ✓ ✓

✓ ✓ ✓ ✓

✓ ✓ ✓ ✓

JR ✓ ✓ ✓ ✓

J0 ✓ ✓ ✓ ✓

J2 ✓ ✓ ✓ ✓

JR ✓ ✓ ✓ ✓

J0 ✓ ✓ ✓ ✓

J2 ✓ ✓ ✓ ✓

JR ✓ ✓ ✓ ✓

J0 ✓ ✓ ✓ ✓

J2 ✓ ✓ ✓ ✓

250 ✓ ✓

250L0 ✓ ✓

250L15 ✓ ✓

300 ✓ ✓

300L0 ✓ ✓

300L15 ✓ ✓

350 ✓ ✓

350L0 ✓ ✓

350L15 ✓ ✓

ASTM ✓ ✓

EN ✓ ✓ ✓

JIS ✓ ✓ ✓

AS/NZS ✓ ✓ ✓

NSHYPER

BEAM

ASTM A6

AS/NZS

3679.1

S235

S275

S355

A36

A572 Gr50

A992

ASTM

Steel

Grade

EN10025

-2

AS/

NZS

Rolling

Tolerance

EN10034

JIS G 3192

AS/NZS 3679.1

Fig. 12 List of corresponding to the standards and the shape

Fig. 13 Available H-beam series table

200 250 300 350 400

400

450

500

550

600

650

700

750

800

850

900

950

1000

Ou

tsid

e w

eb

heig

ht

[mm

]

Flange width [mm]

HE400

HE450

HE500

HE550

HE600

HE650

HE700

HE800

HE900

HE1000 HL1000

IPE400

IPE450

IPE500

IPE550

IPE600

IPE750

UB457x191

UB533x210

UB610x229 UB610x305

UB686x254

UB762x267

UB838x292

UB914x305

UB1000x400UB1016x305

3.2 Size-series variation of NSHYPER BEAM

NSHYPER BEAM has a great deal of size variations as shown in Fig.14.

Following are the advantages of size-series of NSHYPER BEAM toward European

H-beam from the analysis point of sizes, section properties and structural performance.

First, Fig.15 shows comparison of size-series structure between NSHYPER BEAM and

European H-beam, the vertical axis shows web height and the horizontal axis shows

flange width. NSHYPER BEAM has 274 regular sizes and 284 available sizes, European

H-beam has 103 PA common sizes, 58 PA uncommon sizes. This comparison shows that

users can choose optimum size for structural design.

Second, Fig.16 shows that plastic modulus as section properties analysis within a range

of outside web height up to 700mm. In the case of choice of H-beam having 11,000cm3

plastic modulus, Available web height of size-series is between 700mm to 1,000mm. The

benefit of the users is that NSHYPER BEAM provides more “economical” and

“intermediate” H-beam size alternative.

Finally, Fig.17 shows that buckling resistance moment as structural performance analysis.

In the offshore plant fields, a offshore structure has to be designed in consideration of a

twist of H-beam, therefore H-beam having wider flange width has advantage for

structure design. For example, shown in Fig.23, HE1000 x 249 (H 980 x 300 x 17x 26)

can be replaced to HY700 x 350 x 12 x 25, because it has the same strength, and 19.3%

steel amount can be reduced. From the above, NSHYPER BEAM provides more

economical H-beam size by utilizing its wider flanges of 350mm and 400mm.

Availability

Regular Available

Series 42 5

Sizes 328 283

Fig. 14 Size variation of NSHYPER BEAM

Fig. 16 Section properties analysis (Plastic modulus)

Fig. 17 Section profile analysis (Buckling )

Fig. 15 Size structure analysis

HY700

HY750

HY800

HY850

HY900

HY950

HY1000

3.2 High strengthening NSHYPER BEAM

In recent years, the demand of high strengthening H-beam for structure have been

increased, whereby we launched NSHYPER BEAM VE® (Value Ecology &

Economy) series, NSYP®345B, which has 345MPa yield strength more

20MPa than SN490B. As shown in Fig.18, NSYP345B series has same

chemical composition and mechanical properties as SN490B except for the

upper and lower limit value of yield stress.

NSYP345B, uniform-outer-dimension H-beam, has more 20 N/mm2 design strength ,F,

than JIS grade SN490B.Design strength is defined as “the smaller of yield stress and

70% of tensile strength”, and in the case of standard steel, design strength is the

equivalent of yield stress. In the design of steel structure, structural design strength is

obtained by dividing design strength by safety factor, therefore NSYP345B increase

design strength, F, to 345 N/mm2 (more 20 N/mm

2), and permitted to use 1.1 safety

factor. From the above, the steel amount using for construction can be reduced by

using NSYP345B.

3.1 NSHYPER BEAM with weldable structural steels for fixed offshore structures

The abundance of available size-series helps structure design optimize, that’s the reason

why NSHYPER BEAM was developed as replacement Built-up H-beam for Rolled

H-beam. Furthermore, we launched NSHYPER BEAM with EN10225-S355G11+M:

weldable structural steels for fixed offshore structures, which having size-series

advantage as well as low-temperature characteristics, fully complying with steel grade

and other specification based on PTS (Petronas Technical Specification). Fig.19 shows

chemical composition and Fig.20 shows mechanical properties for sections, stipulated by

EN10225-S355G11+M.

temparature Charpy value

test piece [%] [ ̊C] [J]

NSYP345B 12≤t≤16 345～ 465 17≤

SN490B 16<t≤40 325～445 21≤

Mechanical properties

stretch

JIS grade

No.1A

Tensile property Impact property

0 27≤≤80490～610

Yield Point

[N/mm2]

ThicknessSteel grade Tensile strength

[N/mm2]

Yield Ratio

[%]

Steel grade C [%] Si [%] Mn [%] P [%] S [%] Ceq [%] PCM [%]

NSYP345B

SN490B≤0.030 ≤0.015 ≤0.44 ≤0.29

Chemical composition

≤0.18 ≤0.55 ≤1.60

Fig. 18 Chemical composition and mechanical properties table

Steel grade C [%] Si [%] Mn [%] P [%] S [%] Cr [%] Mo [%] Ni [%] Al(total)b

≤0.14 ≤0.55 ≤1.65 ≤0.025 ≤0.015 ≤0.25 ≤0.08 ≤0.50 0.015 to 0.055

Cu [%] N [%] Nb [%] Ti [%] V [%] Nb+V [%] Nb+V+Ti [%]

≤0.30 ≤0.012 ≤0.040 ≤0.025 ≤0.060 ≤0.06 ≤0.08

S355G11+M Cr+Mo+Ni+Cu [%]

≤0.80

Chemical composition

Fig. 19 Chemical composition for sections

Fig.21 shows that adaptable CVN (Crack V-Notch test) specification manufacturing in

Wakayama Works (Sakai Area), Nippon Steel and Sumitomo Metal.

There are 3 important advantages of NSHYPER BEAM with EN10225 -S355G11+M.

First, by using NSHYPER BEAM, shortening fabrication term is capable, such as

eliminating welding and inspection process, free from critical path on Built-H-beam.

Currently, the number of case, which modular construction method for offshore

construction is adopted, has been increasing in high advanced nations having expensive

labor cost, or polar regions and danger area being not able to maintain workforce. At the

case, Built-up H-beam is conventionally adopted, because large section to bear the load

of acceleration of marine and land transportation, and uniform-outer-dimension H-beam

having flexibility for frequent changing of structural design , is needed. NSHYPER

BEAM with low temperature properties has capability for shorter lead time and equal

properties compared with Built-up H-beam.

Second, quality improvement can be achievable without welding process (Fig.22), free

from heat damages and fatigue problems by welding. In a certain project, some problem

happened by using Built-H, such as welding quality: poor penetration, measurements

inconsistency. By using NSHYPER BEAM, these problems can be avoided.

Finally, welding cost on steel work can be reduced without Built-H-beam process.

Fig. 21 Available CVN spec table

○: OK ×: NG

CE PCM

[%] [%] Ft≤25 25<Ft≤40 40<

0̊C ○ ○ △

-20̊C ○ ○ △

-40̊C △ △ ×

Longitudinal

(Location :

1/6F)

A992

A572-G50

EN S355

SN490B

SN490YB

≤0.43 ≤0.25

Availability: H400x200≤, H300x300≤

△: Conditional

Site of

test piece

Test

Temparature

Material

Grade

Nominal thickness [mm]

Test condition of CVN

Tensile strength

Rm

t≤16 16<t≤40 Temp Energy

[N/mm2] [N/mm2] [N/mm2] [%] [˚C] [J]

S355G11+M 460 to 620 355 345 0.87 22 -40̊C 50

Minimum average CVN

impact energy

Steel grade

Minimum yield strength RB

for thickness

RB/Rm

maximum ratio

Minimum on

elongation A

gauge length

Fig. 20 Mechanical properties for sections

Submerged Arc

Welding Machine

Welding Wire

Bottom Flange

Plate Girder

Top Flange

Fig. 22 Schematic of BH Welding process

4. Summary

We developed the manufacturing process that has realized the highly efficient production

of H-beam. In the intermediate rolling mill group, the material is rolled and finished to

the desired thickness, and further, by the use of free-size edging rolls installed in the

edging mill, the flange width of various sizes can be freely rolled

At the final stage of the process, the adjustment of the web height is achieved by the

skewed roll mill, and by using the barrel-length adjustable roll which is installed in the

finishing rolling mill. Furthermore, by using free-size roller straightener, H-beam can be

straightened on line without barrel-length changing.

By using these technologies, the highly efficient production of H-beam with constant

outside web height and flange width, as desired by customers, has become possible.

Currently, constant outside-web-height H-beam of max 47 series, 611 sizes in the size

range from 400 x 200 to 1000 x 400 is achievable. Furthermore, H-beam of various

international standards can be also produced without changing rolls.

By utilizing of abundant size-series structure of NSHYPER BEAM, we launched

advanced steel grade, and provided solution. As high strengthening H-beam for structure,

we launched NSHYPER BEAM VE® (Value Ecology & Economy) series,

NSYP®345B, which has 345MPa yield strength more 20MPa than SN490B.

Furthermore, we launched NSHYPER BEAM with EN10225-S355G11+M grade for

onshore and offshore plant fields, which having size-series advantage as well as

low-temperature characteristics.

The abundance of available size-series and development of various steel grade helps

structure design optimize.

Finally, one of our advantages for users in South East Asia, our geographical advantage

can help shortening lead time. As shown in Fig.23, Sakai Large Shape Mill is closer to

owners, EPC contractors, engineers and module fabricators in South East Asia. In general

case, compare with NSSMC and European mill, lead time from NSSMC of rolled

H-beam is shorter than from European mill, disparity in transport period of about 1

month. This our geographical advantages contribute shortening lead time to help “Fast

Track Projects”.

Fig. 23 Geographical advantage of NSSMC

EUROPIAN

Shape AMERICAN

Shape

UB, UC, HE, IPE

W-Beam

ASIAN

Shape

Extended

JIS Profile

References

1) Inagaki, A. et al.: Shinnittetsugiho. (343), (1992)

2) Saiki, E. et al : Shinnittetsusumikingiho. (401), (2015)

3) Matsuda, K.: South East Asia Iron and Steel Institute Report. 2012