Process & Production Benefits Achieved Using ...

Process & Production Benefits 

Achieved Using 

Electromagnetic Pump 

ZAKAREYA BUALLAY 

Gulf Aluminium Rolling Mill Co 

P.O.Box 20725, Kingdom of Bahrain 

www.garmco.com 

The 3 rd International Melt Quality Work Shop; November 13-16, 2005, Dubai 

1

GARMCO – A brief Introduction 

• GARMCO is an Aluminium Rolling 

Mill company located in Kingdom of 

Bahrain, which produces in excess 

of 151000 tonnes / year of rolled 

product 

• Garmco’s share are owned by six 

Gulf countries as follows: 


2

38% 30% 5% 2% 2% 23% 


3

SCRAPPED ALUMINIUM 

FROM PRODUCTION LINES 

#1 

MELTING FURNACES: (2) 

1. ROUND SHELL TYPE. 

2. TOP CHARGING IS ADOPTED 

TO MINIMIZE CHARGING 

TIME. 

3. REFINING SYSTEM WITH 

FLUXES AND NITROGEN GAS 

BUBBLING IS ADOPTED IN 

PLACE OF CHLORIC GAS 

BUBBLING TO IMPROVE 

ENVIRONMENTAL 

CONDITIONS. 

MOLTEN 

ALUMINIUM 

SOWS 

CASTING 

#2 

HOLDING FURNACE: 

1. RECTANGULAR SHELL AND 

TILTING TYPE. 

2. REFINING PROCESS IS 

CARRIED OUT BEFORE 

POURING TO CASTING 

STATION. 

MELTING FURNACE: 

FEATURES 

ELECTRO-MAGNETIC PUMP 

(EMP) FOR EFFICIENT 

MELTING OF LIGHT SCRAP. 

MOLTEN 

ALUMINIUM 

SLAB 

CASTING STATION: 

1. SETTING METHODS OF 

MOULDS IS SIMPLIFIED TO 

SAVE TIME IN PREPERATION. 

2. MOULD HAS SLIT HOLE FOR 

COOLING WATER TO SECURE 

UNIFORM COOLING. 

3. WITHDRAWAL MECHANISM IS 

RIGIDLY GUIDED TO ENSURE 

LESS DEFLECTION AND LESS 

CAMBER, AND OIL 

HYDRAULICALLY 

CONTROLLED TO ENSURE 

STABLE LOWERING SPEED. 

CHIPS 

1 21 NOV 

2004 

RE-ARRANGED AND FONT ENHANCED. 

17 NOV 

1 2004 UPDATED. NED 

TO REMELT 

SLAB SAW: 

PURCHASED 

SLABS FROM ALBA 

CHIPS FROM 

SCALPER 

1. BAND CUTTING TYPE. 

2. SAW IS DESIGNED TO CUT 

TOP OR BOTTOM PARTS OF 

SLABS. 

SLAB SCALPER: 

1. VERTICAL SPINDLE, 

ONE-SIDE-SCALPING TYPE 

WITH CEMENTED CARBIDE 

TIP BLADES. 

2. SLAB SURFACE IS SCALPED IN 

ACCURATE MIRROR FINISH. 

3. A DRY CUTTING SYSTEM IS 

ADOPTED TO HANDLE CHIPS 

EASILY. 

#3 

#2 

SLAB HEATING FURNACES: (3) 

1. RADIANT TUBE TYPE, INDIRECT 

HEATING SYSTEM IS ADOPTED TO 

MINIMIZE SURFACE 

CONTAMINATION DURING HEATING 

AND SOAKING. 

2. DIRECT DIGITAL CONTROL SYSTEM 

IS USED TO AUTOMATICALLY 

CONTROL TEMPERATURE, PRESSURE 

AND COMBUSTION AIR PRESSURE. 

3. PRONG TEMP. DETECTOR ARE USED 

TO MEASURE INGOT TEMP. AT EACH 

ONE CONTINUOUSLY WITH 

INFLICTING DENTS OR SCRATCHES 

EITHER ON DETECTORS OR INGOT 

SURFACE. 

4. INGOTS ARE AUTOMATICALLY FED 

AND DISCHARGED TO AND FROM 

FURNACES IN STABLE UP-RIGHT 

POSITION. 

#1 

ANNEALING FURNACES: (6) 

1. RADIANT TUBE TYPE, INDIRECT 

HEATING SYSTEM USING 

NITROGEN GAS IS ADOPTED TO 

PREVENT OIL STAINS AND TO 

OBTAIN GOOD SURFACES. 

2. AUTOMATIC TRAY TRANSFER 

SYSTEM IS ADOPTED TO HANDLE 

COIL TRAYS EFFICIENTLY. 

3. FURNACE TEMP. IS 

AUTOMATICALLY CONTROLLED 

BY ZONE CONTROL SYSTEM. 

4. FORCED COOLING SYSTEM IS 

ADOPTED TO SHORTEN COOLING 

TIME OPEN AIR. 

COLD MILLS: (2) 

1. AUTOMATIC GAUGE 

CONTROL AND FLATNESS 

CONTROL SYSTEMS ARE 

ADOPTED TO PRODUCE HIGH 

QUALITY COILS. 

2. X-RAY THICKNESS GAUGE IS 

EMPLOYED FOR AUTOMATIC 

GAUGE CONTROL. 

3. PROCESS COMPUTER IS 

#2 

EMPLOYED TO PERFORM 

VARIOUS AUTOMATIC 

ROLL FORMING LINE: 

OPERATIONS IN IMPROVING 

PRODUCTIVITY AND SAVING 

MANPOWER. 

#1 1. ROLL FORMING IS PERFORMED 

ON SHEETS TRANSFERRED 

FROM CUT-TO-LENGTH LINE. 

4. LOW PRESSURE CO2 TANK 

AND INITIAL STAGE FIRE 

PROTECTION SYSTEM ARE 

2. FORMING UNIT IS EASILY 

REASSEMBLED. 

ADOPTED FOR FIRE 

PROTECTION. 

3. LAYOUT IS SO ARRANGED 

THAT ROLL FORMING CAN BE 

INDEPENDENT IN FUTURE BY 

INSTALLING PAY-OFF REEL, 

ETC. BETWEEN ROLL FORMING 

LINE AND CUT-TO-LENGTH 

LINE. 


HOT MILL: 

COIL 

1. REVERSING AND COMBINATION 

TYPE TO ENABLE ROLLING OF 

AN INGOT INTO A COIL WITH A 

SINGLE MILL. 

2. ROLL BENDING, COOLANT AND 

AUTOMATIC GAUGE CONTROL 

SYSTEMS ARE EMPLOYED TO 

PRODUCE HOT COILS 

DISPLAYING FAVORABLE SHEET 

PROFILE AND LESS DEFLECTION 

IN LONGITUDINAL DIRECTION. 

3. X-RAY THICKNESS GAUGE IS 

EMPLOYED FOR AUTOMATIC 

GAUGE CONTROL. 

4. TEMP. CONTROL SYSTEM IS 

EMPLOYED FOR FINISHED HOT 

COILS. 

5. PROCESS COMPUTERS AND 

PLCs ARE EMPLOYED TO 

ENSURE VARIOUS AUTOMATIC 

OPERATIONS IN IMPROVING 

PRODUCTIVITY AND SAVING 

MANPOWER. 

CUT-TO-LENGTH LINE #1 : 

1. SHEETS OF PREDETERMINED 

LENGTH ARE CUT FROM COLD 

ROLLED COILS. 

2. ACCURACY OF LENGTH IS WELL 

CONTROLLED BY DIRECT 

DIGITAL SERVO SYSTEM, AND 

CUTTING LENGTH IS QUICKLY 

CHANGEABLE. 

3. INTERMEDIATE TABLE IS 

INSTALLED TO TRANSFER 

SHEETS TO ROLL FORMING 

LINE. 

#1 

GARMCO 

FOIL MILL 

#2 

TENSION LEVELLING 

LINES: (2) 

1. COLD ROLLED COIL IS 

CONTINUOUSLY LEVELLED 

UNDER TENSION 

CONDITION INTO STRIP 

HAVING ACCURATE 

FLATNESS. 

2. GOOD ACCURACY IN WIDTH 

IS ENSURED BY TRIMMING 

WHILE LEVELLING. 

3. ACCURATE LEVELLING FOR 

WIDE RANGE OF THICKNESS 

IS ENSURED USING 

LEVELLING UNIT FOR THICK 

OR THIN GAUGE 

RESPECTIVELY. 

CUT-TO-LENGTH LINE #2 : 

SHEETS OF PREDETERMINED 

LENGTH ARE CUT FROM COLD 

ROLLED COILS. 

SLITTING & EMBOSSING 

LINES: (2) 

1. COMBINATION TYPE OF 

SLITTING AND EMBOSSING 

OF COIL IS ADOPTED. 

2. LINE SPEED IS CHANGABLE IN 

TWO STEPS TO PERMIT 

EFFICIENT OPERATION FOR 

WIDE RANGE OF SHEET 

THICKNESS. 

3. SLIT COILS HAVE GOOD 

ACCURACY IN WIDTH AND 

LESS BORE IS OBTAINABLE. 

CIRCLE SHEARS: (3) 

LARGE CIRCLE BLANKS 

FORMED FROM SHEETS 

TRANSFERRED FROM 

CUT-TO-LENGTH LINE. 

CIRCLE PRESS: 

FORMS CIRCLES FROM COILS 

TRANSFERRED FROM 

SLITTING LINES. 

4

Abstract 

• In 2000 GARMCO reviewed recycling 

process of internally generated process 

scrap, particularly scalping chips and Edge 

trims to reduce melt loss & improve yield in 

re-melting of scalper chips. 

• The presentation summarizes the options 

evaluated by GARMCO & results achieved 

out of the investment on electromagnetic 

pump & it’s vortex technology 


5

BACKGROUND 

• GARMCO generate 170 M.T. chips / 

week from scalping of slabs. 

• All loose & baled chips were 

charged in to gas fired melting 

furnaces which resulted in 

following:- 

1. High Melt loss 

2. High dross formation 

3. Reduced melting capacity 


6

GOALS & OBJECTIVES 

• To enhance metal recovery (yield) by 

1. Reduced melt loss 

2. Low dross formation 

• Add additional molten metal capacity. 

• Improve compositional analysis by having 

known chemistry in charge material. 

• Chemical & temperature homogeneity 

• Reduce material handling. 

• Significant annual cost savings (Reduce 

subcontracts for melting scalper chips) 


7

Scalper Chips 


8

Scalper Conveyor for chips 


9

Baling Press - Bales 


10

Options available 

• GARMCO investigated following 

options 

1. Induction furnace 

2. Briquetting machine 

3. Electromagnetic pump 


11

EMP versus Induction Furnace 

comparative Analysis 

• GARMCO selected EMP against 

induction furnace due to following 

benefits 

1. 45% cheaper on operating cost. 

2. Lesser maintenance cost 

3. Recovery is in the range of 98% to 

98.5%. 


12

EMP- Introduction 

• Electromagnetic pump transports 

mass & heat simultaneously as a result 

of forced convection 

• It has controlled sub-surface stirring 

action that helps in rapidly ingesting 

feedstock of varying densities into the 

melt with minimal oxidation. 

• It maximizes utilization of energy 

through better conduction, better 

furnace utilization & hence improves 

productivity 


13

Principle &Function of the EMP 

• The Pump forces liquid metal to flow through inlet 

& outlet tubes connected to furnace. 

• The force is applied on metal by the magnetic field 

based on principle of force applied on current 

carrying conductor (Fleming’s left hand rule) 

• The conductor here is liquid metal 


14

EMP – Main Furnace 


15

Chips collection in bins 


16

EMP - Chips Charging System 


17

Full View of EMP 


18

Chips charging arrangement 


19

EMP - Charging Well 


20

EMP - Charging Well 


21

Metal Transfer to M.F./ casting of Sows 


22

SOWS produced from EMP 


23

Operating Characteristics 

• No physical moving parts within the EMP 

• No direct contact with molten metal. 

• Extremely consistent reliable operation 

• Stirring can be performed throughout the 

melting and/or refining period 

• Controlled velocity subsurface flow 

• Fully controllable stirring, adjustable speed 

& direction 

• Lower Power consumption 


24

99.0% 

98.5% 

98.0% 

97.5% 

97.0% 

96.5% 

96.0% 

98.1% 

98.5% 

EMP Performance (Recovery / Yield) 

98.3% 

97.2% 

97.9% 

98.5% 

98.4% 

97.5% 

97.0% 

98.2% 

97.9% 


98.2% 

97.3% 

Yield (After EMP) 

Target 

25 

98.3% 

2002 2003 Jan-04 Feb-04 Mar-04 Apr-04 May-04 Jun-04 Jul-04 Aug-04 Sep-04 Oct-04 Nov-04 Dec-04

Results &Conclusion 

• Melt loss reduced from 15% to 2% 

• No need to bale the chips any more. 

• Reduced scalper chips inventory to bare 

minimum. 

• Reduced space needed to store chips. 

• Reduced dross formation . 

• No more subcontracts needed to melt chips. 

• Payback period for project cost was just one 

year. 


26

• Thank you 

very much 

• Have a Great 

Day!!! 


27

Process & Production Benefits Achieved Using ... - Pyrotek

Transform your PDFs into Flipbooks and boost your revenue!

Process & Production Benefits Achieved Using ... - Pyrotek

Transform your PDFs into Flipbooks and boost your revenue!

Delete template?

Save as template ?