LATEST CHOICES FOR NEW OR MODERNIZED AUTOMOTIVE C.A.L.s & C.G.Ls FURNACES AND C.G.Ls A.P.C. SECTIONS

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1 LATEST CHOICES FOR NEW OR MODERNIZED AUTOMOTIVE C.A.L.s & C.G.Ls FURNACES AND C.G.Ls A.P.C. SECTIONS 2016 ASEAN Iron & Steel Sustainability Forum Bangkok Session #6 Presentation #3 14 November November /11/2016 1

2 Foreword Either at an initial stage or during modernization, new processes and technological choices for heating and cooling sections combined with process control, present breakthroughs to guarantee: Energy savings and emission reduction, Product quality (mechanical characteristics), Consistent, monitored and smooth operation. 15/11/2016 2

3 Foreword Following choices will be discussed in a holistic approach: Heating: Selective oxidation, heating efficiency and heat recovery, Cooling: Emerging technologies for highest cooling rates (400 C/s without water up to 1000 C/s), heat recovery, A.P.C: New patented cooling technologies choices and their impact on thermal and vibration strip behavior, Control and operation: New patented models principles and strategies, remote assistance, technical assistance. Application on revamping of recent furnaces in China or implementation on new furnaces will be illustrated by case studies. 15/11/2016 3

4 Illustration of CMI global approach New lines: ILVA NOVI LIGURE CGL, Italy is the latest and largest Automotive reference in Europe (unexposed panels & exposed panels for major car-makers), N.S.C/A.M, in Calvert, Al;, USA: two lines (one CGL and one dual line CAL/future CGL) dedicated to automotive material. AK Steel in Dearborn, latest Automotive reference in the USA (GI/GA, unexposed panels & exposed panels for FORD and other major car-makers) Rebuilt of recent lines in China: MAASTEEL new APC to reduce vibrations thanks to implementation of patented Blowstab on a recent furnace supplied by competition SHOUGANG SHUNYI to increase cooling capacity of APC supplied by another competitor On those lines CMI has implemented in a global approach B.A.T. (Best Available Technologies) in heating, cooling and control. 15/11/2016 4

5 Heating Natural gas self-regenerative flameless burners, heat recovery, onoff control concepts and heating strategies more than 85% global furnace efficiency. Average consumption observed is 0.6 GJ/ton for the whole mix on above reference auto CGLs. PP tubes (more than 4000 in operation) 15/11/2016 5

6 Advantages of PPtubes & self rege burners 1. Temperature difference between hot spot and cold spot on a tube is 50 C with PP tube compared to 150 C with W shaped tube. For the same maximum chamber temperature of the furnace, the average temperature is therefore higher with PP tubes than with W tubes heat transfer {k x (tube t ) 4 (strip t ) 4 } is therefore improved. 2. Temperature homogeneity is improved less thermo mechanical stresses in the tubes tubes life time is improved 3. When manufactured out of Inconel plates (3 mm thick), the thermal inertia of the furnace is dramatically reduced compared to centrifugally cast radiant tube (8 mm thick) 4. Finally, due to flameless mode & tube shape allowing fumes recirculation the flame temperature is lowered NOx amissions are reduced (50 ppm 3% O2 in dry fumes is guaranteed while 30 ppm is measured) 15/11/2016 6

7 Other heating solutions COG or LCV gases Preheating section using patented Blowstab using the exhaust fumes from the radiant tubes. Heating/Soaking zone with recuperative type burners (W shaped tubes) or self recuperative burners (PP shaped tubes) with an efficiency of up to 75% Revamping (NG or COG) Existing burners may be replaced by rege burners (2 burners/tube) one on/one off alternance every 20s Combustion efficiency: 85% vs. 62% Tube homogeneity improved 15/11/2016 7

8 Results of revamping on AM auto CGL (COG) Before 12 tubes & 12 burners : installed 1,953 kw 10 tubes & 10 burners : installed 1,628 kw 3581 KW (with efficiency 62% useful for heating: 2,220 kw) After: 14 tubes & 28 burners : useful installed 2,170 kw 12 tubes & 24 burners : useful installed 1,860 kw 4,030 KW (with efficiency 85% useful for heating : 3,425 kw) Results Line total output has been increased by 9.7% for same mix, Gas consumption was increased by 0.4%, Consumption per tons was reduced by 9%, NOx emissions are divided by 2 thanks to the new burners technology. 26 RT 52 B. Strip travel 15/11/2016 8

9 Atmosphere management (CMI preoxidation concept) Exclusive combination of: RTF with a controllable pre oxidation chamber Different atmosphere targets and control before and after chamber Adjustable O2 in the pre oxidation chamber with adjustment per side System to estimate the oxide thickness on each side From single side 1 location to full transversal 2 sides System to control the end of reduction 3 patents pending Concept of separate chamber Control of O2 on edges Global Chamber Control 15/11/2016 9

10 Technologies Cooling in the furnace Different cooling technologies Conventional Jet technologies Patented Blowstab Water mist AcC, etc. Patented Heptane Ultra- Dry Cooling Water dip Quench, TWICE, IWAC. CGL CAL Fluid H coeff.(w/m2.k) Max cooling rate YES YES YES YES YES Air or HNx C/s NO Gas + Water <400 C/s YES Heptane NO Water C/s 15/11/

11 Patented Blowtab Exclusive high performance & anti-vibration cooling No need for upstream and/or downstream hot bridle to increase strip tension no cool buckles No need for intermediate stabilizing rolls between blowing boxes to limit fluttering.(minimum blowing distance of 40mm is OK in industrial lines ) distance between blowing boxes is reduced cooling length = effective length. 105 C/s are industrially achieved for 1mm thick products.with 5% of H2 (150 C/s with higher H2) due to the self stabilizing effect 15/11/

12 Patented ULTRA DRY COOLING (Heptane) To achieve even higher cooling rates CMI s has developed new concept of Ultradry cooling thanks to Alkane media presented in Galvanizers 2009 by Ludovic Ferrand and al and which was successfully tested in a pilot line. 15/11/

13 Patented ULTRA DRY COOLING (Heptane) As a conclusion: Cooling rates of 500 C/sec have been confirmed without strip oxidation in order to preserve coatability. Steel surface is clean after quenching in C7H16 (no carbon layer). Steel coatability remains good, the inhibition layer is not affected by C7H16 quenching. We observe good coating adherence. There is no difference observed between samples cooled with GJC or with Heptane. 15/11/

14 For CALs,CMI has developed the well known technology of HOWAQ (Hot Water Quenching), in use for years in a CAL line. This technology IWAC gives the following advantages thanks to the creation of homogenous steam layer (film boiling regime): Homogenous cooling & auto regulated process Max deviation < 15 MPa for Tensile Strength and Yield Strength along strip width Max deviation < 0.3 % for elongation along strip width Constant efficiency & low energy consumption Flexibility Adjustable rapid cooling rate (200 up to 1500 C/s) and Stop quench (exit temperature is adjustable from 40 to 300 C) energy savings & possibility of new grades (Q&P) 15/11/

15 Choice of cooling technologies 15/11/

16 Blowstab I in auto CGL APC (Maasteel CGL#3) Objectives: To solve issues of APC on equipment supplied by a competitor 6 years ago (fluttering and not enough cooling capacity) To maximize the efficiency of cooling (e.g. to decrease the strip temperature at the top roll), To avoid scratches and twisting effect (current vibration strip 35 to 50 mm ), To keep the existing fans, To deliver 3 months after order, Not to exceed 5 days of line stop, And to minimize CAPEX (investment price). 15/11/

17 Blowstab I in auto CGL APC (Maasteel CGL#3) Installation in 5 days line stop 15/11/

18 Blowstab I in auto CGL APC (Maasteel CGL#3) Results Top roll temperature was reduced by 30 C since Blowstab is more efficient than original design, Vibration of the strip have been divided by 3 (10-15mm instead of 30-50mm): better coating homogeneity no risks of scratches. 15/11/

19 Blowstab II in auto CGL APC (Shunyi CGL#2) Objectives: To solve issues of APC on equipment supplied by a another competitor 6 years ago (Not enough cooling capacity and high electrical consumtion) To maximize the efficiency of cooling (e.g. to decrease the strip temperature at the top roll), To allow product mix extension (max. thickness 2mm instead of 1.6mmà To avoid scratches and twinsting effect, To decrease the electrical consumtion To keep the existing fans, Not to exceed 2 weeks of line stop, And to minimize CAPEX (investment price). 15/11/

20 Blowstab II in auto CGL APC (Shunyi CGL#2) Installation in 2 weeks line stop 15/11/

21 Blowstab II in auto CGL APC (Shunyi CGL#2) Installation in 2 weeks line stop 15/11/

22 Blowstab II in auto CGL APC (Shunyi CGL#2) Results Extension of product mix 15/11/

23 Blowstab II in auto CGL APC (Shunyi CGL#2) Results New strip sizes with thickness between 1.6 to 2.0 can be produced, The fans powers are reduced for thicknesses below 1.6 mm yearly gain of 100,000 USD of electricity 15/11/

24 A brain for your furnace: patented L-TOP This patented software (L-TOP ) integrates physical models (no learning curve) for all furnaces chambers, full automatic operating management (steady, transients, line start, line stop ) includes specific strategies for low output & for product quality improvement.(heat and cool buckles prevention) by real time calculation off hot roll profiles The L-TOP has been already implemented in more than 20 strip processing line furnaces (from which 11 are operating on non-cmi furnaces). 15/11/

25 A brain for your furnace: patented L-TOP Some results 15/11/

26 A brain for your furnace: patented L-TOP Some results Quality: 10 times less risk of heat buckles than with operator or other models Mistracking problems are well reduced Thermal Quality is improved: Material reject due to bad quality are reduced (Lower than 0.2% of out tolerances) Production Production is increased (> 4% and up to 20%) typically between 5 to 10% for automotive CGLs Operation All chambers are under L-TOP management L-TOP manage automatically all operating condition (operators can focus on other tasks) No line stop to implement Consumption reduced by 3% 3 months < ROI < 6 months 15/11/

27 Conclusion Technology choices of one furnace section may vary according to the available utilities and required process but cannot suffer any compromise in a global approach without jeopardizing the whole line performances specially with more and more stringent requirements of CGLs dedicated to automotive. CMI has applied this global approach by implementing Best Available Technologies and patented technologies in each and every furnace component or section for above referenced lines but also has more than 20 references in the past 5 years to retrofit weak sections or equipment (H/W or S/W) of non-cmi furnaces and APC to reach such requirements. 15/11/

28 Michel BOYER Denis WYSOTA Ludovic FERRAND 15/11/