GPI - Product Catalogue

FORGE

GONTERMANN-PEIPERS (INDIA) LIMITED

RegdRegd.Office .Office & Works :

P.O. Pailan, Diamond Harbour Road, 24 Parganas(S),West Bengal,India, Pin : 743512

Phone : 91 33 2453-2455 / 56, 2497-8684-86 / 8294,

Fax: 91-33-2497-8547 / 8686, Website : www.gontermann-peipers.com/

Induction Hardened Alloy Forged Steel Rolls

Alloy Forged Rolls are generally used as Work Rolls for 4 High Tandem Cold Rolling Mills,

Work Rolls & Intermediate Rolls for 6 High Reversing & Tandem Cold Rolling Mills.

Forged rolls are also used as Work Rolls for single stand and Multi Stand cold rolling temper

mill.

• To achieve the above properties, Forged Steel blanks undergo a series of

stringent Heat- Treatment process consisting of Homogenizing, Spherodising,

Normalizing or Volume Hardening (depending on the process requirements) &

polymer Quenching & Stress relieving to minimize internal stresses

• This is followed by low frequency Induction Hardening and post Induction

Hardening Tempering (in a re-circulation furnace) to ensure barrel hardness in

the range of 90 to 100 Sh D, JIS (which corresponds to 800-850 LE)

• For further stabilizing the microstructure the induction hardened rolls are

subjected to “Sub-Zero Treatment” by quenching in liquid nitrogen

• Throughout the manufacturing process stringent process control measures are

adopted to ensure specified quality requirements.

Product Information Sheet

GONTERMANN-PEIPERS (INDIA) LIMITED

RegdRegd.Office .Office & Works :

P.O. Pailan, Diamond Harbour Road, 24 Parganas(S),West Bengal,India, Pin : 743512

Phone : 91 33 2453-2455 / 56, 2497-8684-86 / 8294,

Fax: 91-33-2497-8547 / 8686, Website : www.gontermann-peipers.com/

GONTERMANN-PEIPERS (INDIA) LIMITED

Heat Treatment Capability Drop in Hardness Radial Depth

Hardening Method Work Roll Work Roll

Special Progressive type 8-10 ShD 30 mm

Induction Hardening

Intermediate Roll Intermediate Roll

‘’ 3-5 ShD 35 mm

Typical Carbide Analysis

Carbide Type Carbide Hardness Surface Area Average Diameter

HV %

M3C/M7C3 (850-1100)/(1200-1600) 5-6 0.4-1

Forged Steel Back up Roll

500 X

Nominal Chemical Composition [in %- wt] & Mechanical Properties

[1 MPa = 1 N/mm2 (=0.1 kgf / mm2 )]

Element

%C %Si %Mn %P %S %Cr %Ni %Mo

Tensile

Strength of

Journal (MPa)

Bending

Strength of

Journal (MPa)

Barrel Hardness

in ShC

Min 0.40 0.20 0.30 0.04 0.04 1.50 1.00 0.40 950 1400 55

Max 0.90 0.60 1.00 max max 5.00 max 1.40 1600 2400 70

Hardness in Depth [SH C]

7010 8020 30 40 50 6030

40

50

60

HARDNESS (in ShC)-->

DEPTH FROM SURFACE (mm)--->

70

0

GONTERMANN-PEIPERS (INDIA) LIMITED

Product Information Sheet

Forged Steel Back Up Roll

Alloy steel forged BUR are made from special quality steel manufactured from quality

raw material & ferroalloys through secondary refining& ingot pouring. The ingots are hot

forged and dehydrogenation treatment is carried out. Forged blanks are procured and

going through stringent quality inspection in macro & micro aspects and then processed

successive stages of heat treatment like homogenizing, normalizing to improve the

overall structural soundness, stress distribution uniformity & toughness. It undergoes

differential hardening process followed by mist quenching or compressed air quenching

depending on the hardness requirement upto a desired depth on barrel surface only.The

tempered roll exhibits a uniform bainitic microstructure at the shell & fine pearlitic

structure at the core /neck .

Due to the differential hardening the barrel / working area up to a critical depth only

reaches to critical temperature & hence hardened. The rest core & neck remains

unaffected resulting higher impact strength as well as strength against overload during

the rolling

The above rolls are of following applications-

•Hot & cold mills Back-Up rolls

•Continuous & Semi-Continuous hot strip mills Back-Up rolls

•Roughing 4-High stands Back-Up rolls

•Cold tandem mills Back-Up rolls

•Thick plate mill Back-Up rolls

These rolls are characterized by the following properties :

•Higher hardness penetration

•Improved Wear Resistant property - To provide higher campaign life

•Higher toughness property - To provide more resistance to spalling & fatigue

Recommendations for usage :

• After each rolling campaign the roll barrel surface should be thoroughly ground to

regain original supplied hardness. (max hardness increment of 2 ShC is allowed)

•Between these two varieties choice to be made on the basis of mill conditions as

performance superiority of forged quality roll may get deteriorated due to mill

abnormality.