Ingot Cleanliness Improvements Using Sprue Extensions Beyond The Mold Outlet

Ryan VanderMeulen ArcelorMittal Coatesville April 11, 2012 ArcelorMittal USA Locations

Research Center

Burns Harbor Cleveland

Lackawanna Indiana Harbor

Riverdale Coatesville

Hennepin Conshohocken

Columbus Coatings

Newton Weirton Georgetown

Steelton

Steelmaking and processing facilities Processing facilities Research center

2 ArcelorMittal USA Plate Production Locations

Indiana Harbor Cleveland Riverdale

Conshohocken Burns Coatesville Harbor, Gary

Steelmaking, Rolling, Heat Treating: Rolling & Heat Treating: Steelmaking: Burns Harbor, Coatesville Conshohocken, Gary Indiana Harbor, Cleveland, Riverdale

3 Plate Mills Production Focus • Burns Harbor – 160” – larger, TMCP, Q&T, precise weight – 110” – commodity to 1” – 160” @ Gary – commodity to 1.5”, Q&T • Conshohocken – 110” - commodity, thin, Q&T • Coatesville – – 140” - heavy, varied chemistries, Q&T – 206” - very wide and heavy, Q&T

4 Production Focus

• East Clad, Flamecut, Conversion Most alloy and Q&T Very clean steel Very wide or heavy plate Light thickness plate Small special orders • West Control rolled Precise weight Special surface requirements Very large orders Heat Treated Commodity

5 ArcelorMittal USA Operations Coatesville Steelmaking Process Plan

Electrodes Automatic Automatic Alloys Alloys Wire Feed

Argon Stirring Argon Stirring Ladle Furnace Ladle Degasser

Continuous Bottom Cast Slabs Poured Ingots

Ladle Electric Arc Furnace

6 Ingot Casting Coatesville

• Bottom pouring • Hot topping • Argon shrouding • Maximum size plate 50 tons (45 Mt)

7 Bottom Poured, Ingot Casting

Ladle

Argon Argon Inlet Shroud Hot Top Casting Powder Center Runner Mold

Molten Steel

Runner Brick 8 Products Produced From Ingots

• Thick plates, 3/1 reduction for PVQ; structural grades 2/1; military 4/1 • Heavy plates over ~13.5 sTon • Difficult chemistries – High sulfur free machining grades – Tool steels – Certain military grades – Some unique customer requirements (prequalification) • Grades covering wide thickness range with limited production

9 High Strength Q&T Steels

• A514 family and T-1® Steels, Hardwear® • High strength or abrasion resistance • Flatness requirements 1/2 commercial • Fabrication guidelines

10 A514 Steels

• A514A - to 1-1/4” N-A-Xtra, National • A514B * T-1A® to 1-1/4” • A514E - to 6” ex-Armco • A514F* T-1® to 2-1/2” • A514H* T-1B® to 2” • A514Q* T-1C® to 6” basis for gear rack grades

* PWHT cracking concerns

11 API Offshore Steels

• 2H42 and 50 (N) • 2Y50 and 50T (QT) • 2MT1 (CR, AC) • 2Y60 (QT) • Burns Harbor – AC, N, QT • Coatesville – N, QT – Special Chemistry (Pcm) – Heavy plate, ingot – RP 2Z prequalified Ingot to 3”

12 Pressure Vessel Steels

• Shipped to ASTM A20 requirements • Fabricators export their vessels • Plate export opportunities • Most popular grades A516, A387 - 11/22, A353/553, Clad, A203E, A537, A299

13 A516

• C-Mn steels to 15” (380 mm) thick and 100,000 pounds (45,000 kg) weight • -50oC to +300oC temperature pressure vessel applications, Grades 55, 60, 65 and 70 • Carbon equivalent controls and HIC - testing • Available normalized or Q&T • Similar behavior of A299 steels

14 A387

• Cr-Mo steels to 12” (305 mm) thick and 100,000 pounds (45,000 kg) weight • Grades 11 (1-1/4 Cr - 1/2 Mo) and 22 (2-1/4 Cr - 1 Mo) most popular; other grades to 9% Cr • Elevated temperature pressure vessel applications • Temper embrittlement resistance • Post weld heat treatment (stress relief) • Available N&T or Q&T

15 Roll-Bonded Clad

• Composite of economical “Backing Steel” and high performance alloy – examples: A516/304L, A387/410S, A36/C276 • Assembly of a “Clad Pack” • Cost advantages • Fabrication procedures - forming and welding • Pressure vessels, FGD systems, pulp and paper equipment Nickel Layer Backing Steel Spacer bars

16 Alloy Inserts Parting Compound Military Armor

• Navy Armor Steels - HY-80 & 100, HSLA-80 & 100 - surface ships and submarines • Army Armor Steels - moderate and high hardness grades - M-1 tanks, other vehicles • Require Q&T and Fineline® • Special testing - first article, ballistic • Plates from ingots used particularly in Carriers

17 AISI Alloy and Mold Steels

• Chemistry only grades • Most popular 4140, 4142, 4130, 8620, 4340 • All vacuum degassed, some may be Clean-Cut or Fineline • Thermal cutting and quench cracking concerns • Used in variety of tooling applications, including MTD steels

18 MTD® Steels

• Mold, tool and die pre-hardened steels for plastic injection molds and holder blocks, 262-321HB* • MTD #1 - N&T 4142 used to 6-1/2” thick • MTD #2 - Q&T 4130 used to 12” thick • MTD #3 - Q&T .30% carbon, Fineline quality to 12” thick; ingot only for internal quality, BEU where possible • MTD #4 - N&T 4150 used to 6-1/2” thick • MTD #1, #2, #4 may be Clean-Cut quality

* MTD #1 and #4, to 3”: 241-320 over 3 - 6-1/2”

19 Free Machining Grades

• Higher sulfur levels for improved machinability • Clean-Cut® 20 and 45, .06/.12 sulfur, two carbon levels, calcium treated to 15” thick • C1119 mod. and C1144 mod., .24/.33 and .20/.33 sulfur levels always ingot • Clean-Cut® Alloy Steels, .02/.04 sulfur, calcium treatment available in 4140, 4142, 4150, 8620, MTD #1, #2 and #4

20 Tool Steels

• Cold work tool steels - A2, 01, S7, S5, D2, A8 mod. • Mostly ingot produced at Coatesville, some melted off-site – D2 ingot from outside source – S5 can be strand cast • Long processing cycles • Produce full sized plates that customers can cut into bars • Flatness tolerances are critical for cutting and machining

21 Bridge Steels

• Industry push to use ASTM A709 • Grades 36 through 100 ksi yield • Three zones for determining CVN impact requirements, also fracture-critical member criteria • New HPS 50W/70W/100W • Ingots used in thick, wide &/or long plates 22 Flame-Cut Products

• Oxygen-fuel or plasma cutting of all grades, thicknesses and weights of plate we can roll • Beveling of edge detail/weld preparation to drawing specifications • Plates/parts can be press flattened to meet tolerances • Finished pieces used in structural and sub-assembly, forming, fabrication and machining applications

23 Common Ingot Quality Issues

• Cracks – Rate of Rise – Mold Centering • Hot Top Fins – Board Fit in Molds • End/Side Laminations – Solidification – Rolling • Pipe/Burst/UT Failure – Solidification – Cooling – Trapped Junk 24 Potential Sources of Trapped Junk

• Foreign debris including cardboard • Damaged Refractory Brick • Nalcosil • Runner Sand • Fluxes/Powders – most common HT2

25 Ladle Sand

• Prevents steel from escaping through the outlet • Protects opening of ladle from damage • Allows for better flow of steel

26 Refractory Brick

• Can be easily fractured or crack • Uneven plates cause bricks to be misaligned

27 The ‘Trap’

28 The ‘Trap’

14” Double Male Straights 9” Slotted Outlet Sprue Cap

29 Picture of Sprue

30 End of Sprue

31 Diagram of Sprue

END AB 1” C 4” D 6” E OUTLET

0 .5” 1” 2” 2.5” 6.5” 7” 13” 13.5” Distance from the End to Outlet

Note: A, B, C, D, E are all ½”

32 End Pieces

• Where most junk was found • Not fully circular Melt No.- Position C0082 C0086 C0192-1 C0192-3

33 Definition of Junk

• All non-metallics • Material on edge of piece extending deep into the surface • For air bubbles, only parts that appeared to have been non-steel material

34 Trapped Inclusions for C0082/C0086

4.0%

3.5%

3.0% n o i

s 2.5% u l c C0082 n

I 2.0%

t C0086 n e

c 1.5% r e P 1.0%

0.5%

0.0% 0 2 4 6 8 10 12 14 Distance from End to Outlet (inches)

35 Trapped Inclusions for C0192

18% 16%

14% n

o 12% i s u l c 10% C0192-1 n I

t C0192-3

n 8% e c r

e 6% P 4%

2% 0% 0 2 4 6 8 10 12 14 Distance from End to Outlet (inches)

36 Percent Inclusion by Piece

Piece C0082 C0086 C0192-1 C0192-3

A 3.8% 3.6% 13.3% 15.8%

B 1.2% 0.59% 9.8% 6.5%

C 0.17% 0.08% 3.9% 6.0%

D 0.17% 0% 2.8% 7.6%

E 0.12% 0% 0%

Total % Inclusion 0.42% 0.25% 3.3% 5.5%

37 Indication of Swirling Motion

C0086 C0086 B A

C0192-1 C0192-3 D D

38 Middle Location of Junk 50% of 1.06” Outside Area 1.5” 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% C0082 C0086 C0192-1 C0192-3 Middle % 6.7% 2.2% 27.3% 25.1% Outer % 93.3% 97.8% 72.7% 74.9%

39 Flow Model

Center Runner Mold

‘Trap’

Sprue 40 Flow Video

41 Cost

• Refractory cost increase per ingot of ~3%. • Worst-case yield loss of ~0.1%. • Total cost increase under $1.00/ton. • One trapped junk rejection = $5,000+ depending on size and grade. Can be over $20,000 for large armor ingots.

42 Follow-Up Work

• Work with vendor to develop a standard “trap brick” • Integrate trap usage into all special heats to start • Make traps standard for all heats

43 Conclusion

• Demonstrated ‘Trap’ is capable of catching junk • Minimal cost and yield loss • Potential to produce cleaner ingots and reduce the number of rejections

44 Questions?

45