FerryNod®

Ferry Capitain’s reference for girth gears

150

200

250

300

150

Cont

rain

te a

dmis

sibl

e de

réf

éren

ce

(flex

ion

- σFl

im -

N/m

m2 )

Dureté superficielle HBW

310 330 350290270250230210190170

450

500

550

600

650

700

150

0 1 2 3 4 5 6 7

310 330 350290270250230210190170

750

800

Cont

rain

te a

dmis

sibl

e de

réf

éren

ce

(pre

ssio

n de

con

tact

- σ H

lim -

N/m

m2 )

Dureté superficielle HBW

0 1 2 3 4 5 6 7

0

Har

dnes

s (H

B)

Depth (mm)

Hardness vs Depth for a SGI gear

-10 -20 -30 -40 -50 -60 -70 -80 -90 -100 250

260

270

280

290

300

310

320

330

340

350

Too

th r

oot

= 2

.25

x m

M18 M25,4

Too

th r

oot

= 2

.25

x m

M34

Too

th r

oot

= 2

.25

x m

M40

Too

th r

oot

= 2

.25

x m

(BH

N)

Microstructure The matrix evolves as a function of hardness as follows : • FerryNod® 250 to 270 : pearlitic • FerryNod® 280 to 300 : pearlito-bainitic • FerryNod® 310 to 340 : bainitic

FerryNod®

graphiTe

BAINIte

pearliTe

perlitic Bainitic

Physical properties guaranteed1

FerryNod® is a ferrous alloy grade that covers a hardness range from 250 BHN (FerryNod®250) to 340 BHN (FerryNod®340).It allows guaranteed minimum mechanical properties and hardness in thick cross-sections (>100 mm). FerryNod® material grades do not have direct equivalents in published standards.FerryNod® Grades 320 to 340 are the subject of technical patents.

hardness

• Range : from 250 to 340 BHN (minimum guaranteed on casting) • FerryNod® is a very homogenous material: on a 200 mm thickness cross-section, the maximum hardness

loss is 5 BHN.

Hardness gradient along tooth root

perlito-Bainitic

• tensile properties obtained from test bars machined, with integrally-cast test blocks. • Fatigue limits specific to gearing are as specified by ISO 6336 Grade Me and AGMA 6014 grade M2. • the same standard, non destructive , test methods (e.g., Ut, MP, …) applicable for steel are used to verify the soundness of the castings, even for cross-section thicknesses exceeding 1000 mm.

Material standard eN 1563 does not specify minimum mechanical properties for high hardness material, having thick cross-sections (see table below).

Mininum mechanical properties guaranteed beyond material standard limits 2

Material grade Section thickness

Yield strength 0,2%

Tensile

Strengthelongation

Designation Numbert

mmRp 0,2Mpamin.

rmMpamin.

a%

min.

eN-GJS-800-2 5.3301t≤30

30<t≤6060<t≤200

480 800 2

* to be specified and agreed upon by supplier and purchaser

eN-GJS-900-2 5.3302t≤30

30<t≤6060<t≤200

600 900 2

* to be specified and agreed upon by supplier and purchaser

FerryNod® bridges the gaps in the specification by guaranteeing mechanical properties on thick cross-sections.

tensile testing Fatigue testing

grade

tensile Strength (Rm)

min. (MPa)

Yield Strength

0,2% (Rp0,2)

min. (MPa)

A%

Fatigue Limit

tooth root σFlim min.

(N/mm²)

Fatigue Limit

tooth flank σFlimmin.

(N/mm²)

FerryNod® 250 750 540 3 229 625

FerryNod® 270 790 550 3 237 655

FerryNod® 280 800 550 2 240 670

FerryNod® 285 810 560 2 242 678

FerryNod® 290 820 560 2 244 685

FerryNod® 300 850 570 1 248 700

FerryNod® 310 870 570 1 252 715

FerryNod® 320 890 580 1 256 730

FerryNod® 330 910 590 1 259 745

FerryNod® 340 930 600 1 263 760

Minimum mechanical properties values guaranteed by FeRRY CAPItAIN for FerryNod® grades

Field Repair

A material dedicated to open gearing applications3

4

Gear design standard ISO6336, Section 5, specifies the maximum allowable contact (tooth flank σhlim) and bending (tooth root σFlim) stresses as a function of material hardness (see graphs below). FerryNod® grades meet or exceed the specified stress values of this standard.

ISO6336 does not specify allowable stress values for hardness above 300 BHN. FerryNod® 310 to 340 material grades allow the limitations of the standard to be exceeded, and to achieve higher allowable contact and bending stresses.

Welding trials and mechanical testing conducted specifically on SGI gear teeth have shown that a serviceable repair on an installed gear is possible, with only minor losses in fatigue strength. As such, any production stoppages due to damaged gearing should be minimized. Ferry Capitain has established a formal repair procedure (PR2/89).

FeRRY CAPItAINa Groupe CIF company

Vecqueville - Usines de Bussy - BP33 - 52300 JOINVILLe - France tel: +33 (0)325 94 04 24

www.ferrynod.com // ferrynod@ferrycapitain.fr

Créd

its p

hoto

: Fe

rry

Capi

tain

- G

etty

Imag

es -

RCS

Nan

terr

e B

492

007

372

- ww

w.le

-fil.f

r

150

200

250

300

150

Cont

rain

te a

dmis

sibl

e de

réf

éren

ce

(flex

ion

- σFl

im -

N/m

m2 )

Dureté superficielle HBW

310 330 350290270250230210190170

450

500

550

600

650

700

150

0 1 2 3 4 5 6 7

310 330 350290270250230210190170

750

800

Cont

rain

te a

dmis

sibl

e de

réf

éren

ce

(pre

ssio

n de

con

tact

- σ H

lim -

N/m

m2 )

Dureté superficielle HBW

0 1 2 3 4 5 6 7

0

Har

dnes

s (H

B)

Depth (mm)

Hardness vs Depth for a SGI gear

-10 -20 -30 -40 -50 -60 -70 -80 -90 -100 250

260

270

280

290

300

310

320

330

340

350

Too

th r

oot

= 2

.25

x m

M18 M25,4

Too

th r

oot

= 2

.25

x m

M34

Too

th r

oot

= 2

.25

x m

M40

Too

th r

oot

= 2

.25

x m

Bending stress (tooth root)Contact stress (tooth flank)

Hardness BHN Hardness BHN

150

200

250

300

150

Cont

rain

te a

dmis

sibl

e de

réf

éren

ce

(flex

ion

- σFl

im -

N/m

m2 )

Dureté superficielle HBW

310 330 350290270250230210190170

450

500

550

600

650

700

150

0 1 2 3 4 5 6 7

310 330 350290270250230210190170

750

800

Cont

rain

te a

dmis

sibl

e de

réf

éren

ce

(pre

ssio

n de

con

tact

- σ H

lim -

N/m

m2 )

Dureté superficielle HBW

0 1 2 3 4 5 6 7

0 H

ardn

ess

(HB

) Depth (mm)

Hardness vs Depth for a SGI gear

-10 -20 -30 -40 -50 -60 -70 -80 -90 -100 250

260

270

280

290

300

310

320

330

340

350

Too

th r

oot

= 2

.25

x m

M18 M25,4

Too

th r

oot

= 2

.25

x m

M34

Too

th r

oot

= 2

.25

x m

M40

Too

th r

oot

= 2

.25

x m

the presence of graphite nodules provides inherent lubricity and enhances a better vibration damping properties

... and provides higher resistance to crack propagation (see photos)

SteeL - crack propagates freelyFerryNod® : crack is arrested/absorbed by graphite nodules

am

plitu

de

Ductile & malleable irons

Gray iron

Time

Specific advantages

Steel

Allo

wabl

e str

ess -

σh

lim- N

/mm

²

Allo

wabl

e str

ess -

σFl

im- N

/mm

²