Ryker Plant consists of a gas controlled shaft furnace, a modular Hazelett twin-belt caster, a caster station and a rolling mill with 12 individually driven roll stands, followed by a cooling section, a coiler and coil handling facility for automatic compacting, strapping and packing of the finished wire rod coils with a casting capacity of 35 t/h and annual installed production of 2,25,000 MTPA. Due to newly designed Lambda gas control system and use of variable frequency controlled drivers for blowers and mill stands, this plant would be one of the most economical and ecological of its kind. The new design of the charging equipment allows for a loose and even distribution of the charged material and the utilization of nozzle mix burners with individual control result in a higher heat efficiency, lower gas consumption and comparatively low oxygen pick up of liquid copper. The concept of straight line casting without bending ensures a fine grained and homogenous casting structure with equal distribution of oxygen and impurities. Friction free rolling due to 12 single drives with frequency controls for each drive results in long lifetime of roll rings and high surface quality of the end product. The fully integrated control system with closed loop process control via PLC system ensures high plant availability. The PC’s are connected with a fast network to form a uniform control system. A data logging system stores important plant parameters e.g. temperatures, casting speed, combustion gas analysis etc.
Electrolytic refined Grade A copper cathodes confirming to international standard ASTM B-115 and EN-1976 are melted with controlled atmosphere in vertical shaft furnace and transferred into the holding furnace through metal transport launders. State of the art Hazelett twin belt casting machine ensures symmetrical cooling of the rectangular casting section by 2 belts and 2 dam blocks. With the assistance of automatic metal feeding and level control system, copper bar is continuously cast and then rolled to rods of various diameters by hot rolling mill. Following to hot rolling, the copper rod passes through the pickling line for surface de-oxidation, cooling, brightening and then is packed into coil form for shipment.
Step-wise main stages for copper rod manufacturing are as follows:
- Charging copper cathodes into the shaft furnace by the skip hoist and melting of the metal.
- Preparation of metal for casting in the holding furnace.
- Continuous casting rectangular copper bar on the caster.
- Rolling of continuously cast in the rolling mill.
- Cooling and brightening of copper rod.
- Coating the copper rod with anti-corrosion wax layer.
- Coiling of the copper rods into coils.
- Weighing, packing, warehousing and shipping of the finished product.
- Impurity analysis Spectrometer by Spectro Analytical Instruments.
- Direct reading optical emission spectroscopy technique is used.
- Surface of sample is first ground flat and placed against the Spark stand where it is flooded with argon and rapid series of high current sparks produced. Small quantity of sample surface is evaporated and emits light. These light signals are then recorded by array of Photo Multiplier Tube (PMT) and Charge Coupled Device (CCD) detectors simultaneously. After calibration, the technique provides a qualitative elemental analysis of the metal sample.
- Self-regulating purification system and temperature absorbent design without water cooling.
- Integrated shutter system for optimum plasma viewing and minimized argon consumption.
- Oxygen content analyzer by LECO Corporation.
- Used for measurement of oxygen content using inert gas fusion technique.
- Pre-weighed sample is placed in a graphite crucible which is heated in an impulse furnace to release analyte gases. Oxygen present in the sample reacts with graphite crucible to form CO and CO2. An inert gas carrier, typically argon or helium sweeps the liberated gases out of the furnace and through a mass flow controller. The gas flows through a heated reagent where the CO is oxidized to form CO2 and H2 is oxidized to form H20. Oxygen is detected as CO2 using a non-dispersive infrared cell. CO2 and H20 are then scrubbed out of the carrier gas steam.
- State of art infrared and thermal conductivity detectors with no moving parts and no manual adjustments.
Universal Testing Machine
- Tensile stress and compressive testing by Shimadzu Corporation.
- High quality test data and diverse system lineup.
- Controller with high level of operability and safety.
- Offers real-time auto tuning of control parameters, based on measured test force and strain data.
- Accurate S-S curve with high precision load cells.
Twist Torsion Machine
- Twist torsion analysis by Filowire Inc.
- Used to determine the behavior of copper rods when twisted or under torsional forces as a result of applied moments that cause shear stress about the axis
Surface Oxide Determiner
- Film thickness using Surface oxide Determiner from Southwire.
- Zero-maintenance reference electrode.
- Resistance measurement by Kelvin Bridge from Toshniwal.
- Two or four terminal measurements can be performed.
- Suited for measuring low resistances.
Eddy and Ferro Defectomat
- Non-destructive testing for surface flaws by Eddy and Ferro Defectomat from Dr. Foerster.
- State of art computer technology and network integration.
- Continuous display of key test parameters.
- Precision marking in exact location.
RBPL Plant Process and 3-D layout
Features and Description
- Flexible charge system consisting of charging car with winch and motor assembly to charge copper cathodes to shaft furnace.
- Special skip design for improved cathode dispersion and scrap box for easy scrap handling.
- Lifting capacity – 3.5 MT.
- Safe operation, less downtime and less interruptions of melting process.
- Loose and even distribution of charge material in furnace shaft for better heat transfer.
- 19 nozzle mix burners arranged in 3 rows with automatic control of combustion gas mixture of each burner.
- Melting capacity – 35 MT / hr.
- Lined with heat resistant and chemically inert refractory.
- Furnace diameter – 2.65 m, Furnace height – 12 m, conical shaped stack of 8 m height is placed over it. Total height of stack – 26 m and Height of chimney – 36 m.
- High thermal efficiency resulting in lower fuel consumption.
- Low oxygen content in liquid copper to ensure quality for final rod.
- Easier maintenance due to zero regulator free burner supply system.
Covered Transfer Launder
- Molten metal is transferred from shaft furnace to holding furnace via covered and gas heated connecting launder.
- Lined with special refractory material and equipped with launder burners.
- Lower fuel consumption and low oxygen pick up.
- Steel plate housing of horizontal drum type.
- Equipped with 2 tilting cradles and a sectional steel frame.
- Rotates around an axle arranged eccentrically from furnace axis and is lined with refractory material.
- Sufficient capacity of 20 MT ensures continuous running of shaft furnace during production stops in the rolling line and enables constant temperature of liquid copper.
- SCADA operated process ensures controlled supply of molten metal to casting machine.
- Less downtime and less interruptions of melting process.
- Lower fuel consumption for shaft furnace by continuous operation.
- Lower oxygen pick up during stops of shaft furnace.
Hazelett Twin Belt Caster
- State of art straight line casting without bending.
- Metal static pressure during solidification of the liquid copper ensures no center porosity.
- Molten metal from holding furnace will flow through second launder to turndish.
- Twin belt caster mould has a straight, symmetric and rectangular form.
- Symmetric cooling of the rectangular casting section by 2 belts and 2 dam blocks results in even distribution of oxygen and impurities.
- Used for cutting the cast strand during the starting phase and in case of trouble and chamfering the edges of the cast strand at an angle of 45°.
- Hydraulically driven.
- After the cut the pendulum shear is returned to its initial position by a pneumatic cylinder.
- The cut-off strand pieces are pushed to the scrap buckets by a hydraulic push-off device.
Bar Preparation Unit
- Consists of pinch roll set, automatic hydraulic shear with hydraulic scrap bar guiding device for automatic operation, edge scalping machine for chamfering the cast bar edges and a spraying unit.
- Less stops of melting and casting process for minor stops in rolling mill.
- Less downtime for new start-ups i.e. higher availability of the rod line.
- Less copper losses for edge scalping due to slave movement of cutter head.
12 Stand Rolling Mill
- 12 individual driven roll stands.
- First 6 rolls are roughing rolls with diameter of 360 mm.
- Last 6 rolls are finishing rolls with diameter of 220 mm.
- Larger diameter of mills results in better forging effect to remove defects from the cast copper bar.
- Both rolls of all stands are symmetrically adjustable. It allows re-machining of roll rings up to 10% of diameter and exact straight line rolling.
- Individual drive design technology allows tension free rolling and results in long roll ring life.
- High pressure descaling system assures reduction of the scale formation.
- Fine grained and homogenous rolling structure with equal distribution of oxygen and impurities.
- Less process costs for roll rings according to less wear and possibility for re-machining of roll rings.
- High flexibility in final product dimensions as round and flat sections.
- Use of more robust and maintenance friendly frequency controlled AC motors reduces maintenance time.
De-oxidation and Cooling Line
- Isopropyl Alcohol based de-oxidation line.
- Rolled rod can be cooled down to 80° C to prevent re-oxidation.
- Rod passes through Defectomat unit and Waxing unit before reaching laying head.
- Bright rod surface with low thickness of oxide layer of 350 A.
Laying Head and Coil Forming Station
- Designed for collecting of coils into orbital or spiral coil types.
- Integrated in coiling equipment is a lifting device for good coil shape and waxing device for surface protection of the final rod.
- Compacted hydraulically.
- Converted with HDPE sheets and finally strapped with PET straps.
- High flexibility to customers’ requirements of coil sizes.
- 2 individual emulsion systems with automatic dosing pumps for alcohol, oil and neutralizer for roughing and finishing stands.
- High flexibility of emulsion composition according to requirements of rolling process.
- Less process costs for roll rings due to higher lifetime in combination with single driven stands.
- Better rod surface.
Electrical Control Equipment
- Control of complete process is done by PLC system.
- AC-drive technology for rolling mill drives with frequency converters.
- Visualization system of the whole line with diagnostic signaling and monitoring software.
- Good accessibility of process data for trouble shooting.
- Less downtime for the line.
- Low maintenance for AC-drives, high speed control of rolling speed.