9th ECCC European Continuous Casting Conference – ECCC 2017

Over the last 50 years, continuous slab casting processes have been widely installed over the world taking advantage of their enhanced productivity, yield, energy consumption and labor efficiency. Nowadays, the continuous slab casting can be divided into four categories as casting thickness: strip casting, thin slab casting, thick slab casting and ultra-thick slab casting processes. ...

Cooling Zones at casting machines are typically equipped with air-mist nozzles to guarantee a wide turn down ratio (typically 1:9) from highest to lowest water flow at a constant spray pattern. To prevent corner cracks the Zones are additionally split into center and margin strips across the casting width. Primetals Technologies DynaJet Flex is the new cooling system to bring the...

Non-metallic large inclusions are detrimental to most physical and chemical properties of steel and require a removal treatment. Inclusions can provide crack nucleation sites, surface defects, corrosion sensitivity and will reduce mechanical properties. Gas stirring in the ladle is commonly used in secondary steelmaking to homogenize chemical composition of alloy elements and temperature and...

Changing market situations demand sustainable usage of new available technologies to support steel producers with highly flexible plant configurations and tools. Therefore investments are focused to optimize production costs and product quality with short-term return. Modular design of upgrade solutions provides an individual configuration of metallurgical process-optimization respecting...

Secondary cooling is an important process in continuous casting in the steelmaking division from the viewpoints of stable industrial operation and the quality of cast slabs. Historically, hydraulic spray nozzles were originally used in the continuous casting process, but mist spray nozzles were developed subsequently to prevent clogging of the nozzle tip and surface cracks of cast slabs....

Dillinger has put into operation a new continuous caster. The fully vertical machine is equipped with 2 strands of a nominal widths of 2200 mm. The thickness varies from 300 to 500 mm in 50 mm increments. Each strand consists of 9 segments allowing the caster to align the slab optimally at any position during the casting process. Soft reduction adjustment of the segments guarantees lowest...

The decrease of first slabs downgrades and the reduction of clogging on specific alloyed steel grades to increase product quality and extend casting sequence have been one of the priorities of Aperam Genk continuous casting team. High steel quality levels and particularly cleanliness have to be achieved at the beginning of the cast. Tundish filling has been studied along with the influence...

Steel cleanliness is a complex topic, which is influenced at almost every step in the production line. It starts on the liquid side in the converter and ends in the solidified slab, and is further topic to modification by heat-treatments or rolling. To produce and provide high quality steel, the steelmaker has to be able to control the inclusions in the as cast slab, where inclusions can range...

In continuous casting secondary cooling the cooling intensity has to be accurately adjusted in order to achieve the desired strand surface temperature. The cooling intensity can be varied by changing the water flow rate through the nozzle. For a homogeneous cooling effect the nozzle flow rate must not drop beyond a nozzle-specific minimum value. In many cases lower cooling rates are required,...

The challenging task assigned to Danieli in April 2014 involved revamping the single-strand slab caster on a turnkey basis, within a compressed shutdown period of four weeks, including the entire schedule for dismounting, erection and commissioning. Danieli, in close cooperation with the ArcleorMittal Industeel project team, completed all the activities including design, manufacturing,...

Puyang steel, one of China’s leading private steel producers, extended its grade portfolio to very demanding steels with the new caster being designed for a yearly production of 1.2 million tons of not only peritectic micro-alloyed and high-strength steels, but high carbon and boron-alloyed steels, high quality construction steels and pipeline grades. The slab format covers a medium size...

In the initial secondary cooling zones for the radial slab caster it is necessarily to keep the following conditions: set the hard cooling to remove a large amount of heat when keeping the cooling uniformity to avoid overcooled corners. In these days the problem how to satisfy these requirements is handled by using more cooling nozzles in the one line with water overlapping areas. This paper...

Superheat is essential for the continuous casting process. It is the amount of temperature above the Liquidus temperature, which ensures to keep the steel in liquid form until it reaches the mold. Once at the mold the superheat is removed and the steel is allowed to solidify in a controlled manner. If superheat is too high, the steel might not solidify in the mold causing breakouts. If...

The proposed paper describes the application of a measurement system (CasTemp® from Heraeus Electo-Nite) for observing the heat temperature in the tundish near the stopper continuously. The knowledge of the temperature in this region is essential for monitoring and estimating flow conditions in the tundish (and therefore making assessments on the separation behalf). Furthermore it’s very...

In the secondary cooling zone of the continuous casting process the steel is cooled down by water and water/air nozzles. The cooling has to be sufficient enough to ensure a certain shell thickness and finally the complete solidification of the material. Further a controlled and uniform cooling strategy is important to minimize the amount of defects in the solidified steel. To determine the...

The field of computer-assisted layout engineering and material flow planning and evaluation has gained considerable interest in the last years, mainly thanks to the evolution of advanced numerical modeling tools. Danieli has developed a state-of-the-art solution with a dedicated set of simulation libraries able to model the logistics of the entire meltshop, from scrap yard through melting and...

Non Metallic Inclusions in the slab may cause clean steel defects such as slivers, blow holes and laminations. The main inclusions found in these defects are mould slag particles, argon bubbles accompanied by alumina or sometimes by slag particles and calcium aluminates. In some occasions clogging products are found. When doing root cause analysis to the origin of these clean steel defects...

Flows in CC mould are a key parameter to control products quality. Mould Flow Monitoring (MFM) is a solution developed by Amepa Company. It is an electromagnetic technique using sensors implemented behind the copper plate of the mould which consist in permanent magnets and several highly sensitive detectors without direct steel contact. These sensors are able to measure the velocity of liquid...

A competitive landscape pressurizes the steel producers business, zero defect requirements from customers forces the producers for additional efforts in process control and quality management. The so called quality related cost, which include also rework, cost for downgrading or even scabbing of material is already a remarkable lever in a plants profitability breakdown. The introduction of...

ArcelorMittal Tubarão (AMT) is located in the State of Espírito Santo, southeast of Brazil. AMT has been in operation since November of 1983, and its main products are steel slabs and hot rolled coils. By using continuous improvement in the production process, maintenance and the latest technologies and equipment, AMT is aiming to increase the production of liquid steel at its steelmaking...

In modern manufacturing, which aims at maximum productivity and quality assurance, it is essential to make use of high-grade materials, a well thought-out design, the latest coating techniques and intelligent sensor technology. System solutions that utilize new sensor technologies with “Industry 4.0” in mind open up a wide range of possibilities also in the field of continuous casting....

An innovative development was carried out to improve fatigue life of bearing steel at West Japan Works Kurashiki, JFE Steel Corporation. First, in order to prevent contamination at the continuous casting, sand filled in the nozzle of ladles is discharged just before starting continuous casting. Secondly, the main composition of tundish flux was modified for better melting...

In May 2015 the modernized slab caster No. 3 in Hüttenwerke Krupp Mannesmann GmbH (HKM) Duisburg-Huckingen plant in Germany went into operation. The revamp was done by Primetals Technologies Austria, with the targets of enhancing quality and product tolerances of the slabs produced, widening the product portfolio, and improving process stability, availability, and workplace safety. For...

In the continuous steel casting process ladle shroud is used as a protective device or device developing the pattern of liquid steel and non-metallic inclusions motion. With the appropriate construction of ladle shroud, the hydrodynamic structure of liquid steel motion can be effectively modified in the tundish. The facility under investigation is a single-nozzle slab tundish. For the examined...

A computational fluid flow model has been developed to simulate the flow field of liquid steel within the square mold region of a billet caster. This study reports on the dramatic effect that a Submerged Entry Nozzle’s (SEN) position can have on fluid flows developed in square, curved mold, billet casters. In this study, ANSYS Fluent 14.5 software was used to model the 3-D turbulent flow of...

Increasing quality requirements on continuous casting products lead to the necessity of getting detailed information on physical phenomena occurring in the mould. Temperature measurements help to control the beginning solidification, e.g. with a sticker warning system. Up to now measurements with thermocouples are the state-of-the-art. An alternative is presented here with a fibre optical...

Electromagnetics is a well-established method to control steel flow patterns in the (slab) casting process. Improvements of process stability, surface and subsurface quality for a variety of casting conditions have been widely reported with the use of mold electromagnetic devices. Building on the success and flexibility of the braking and stirring capabilities of the FC Mold, a supplementary...

The flow pattern in the tundish is critical for final product quality, as it influences the cleanliness of the steel entering the mold. Poor tundish practice can lead to surface level fluctuations, eroded refractory particles and cold regions, leading to defects in the cast product. On the other hand, by achieving an optimal flow pattern, it is possible to not only prevent inclusion formation...

The paper shows the results of the research obtained by industrial experiments with use of different dams in the tundish. The number and distribution of the inclusions for different positions of ultra-low carbon steel slabs were also analysed by Aspex. The industrial experimental results showed that: the average inclusions at dam without hole and with hole in the tundish are distributed...

It is well known now that the cast product defects like hot tears or cracks are rooted at the first beginning of the solid shell birth. Damages result from the competition between hydrostatic pressure within the turbulent flow exit from the SEN and the solidifying skin under tensile stresses and strains state. In addition, the thermal energy extracted from the cast product by the mold has huge...

The dual strand casting machine CC No.4 at Linz steel plant is the eldest machine in operation and casts 215 mm thick slabs of ultra-low carbon, low carbon and HSLA steel. Recently bothering sliver defects appeared on the hot bands in a certain width range of approx. 1000 to 1200 mm when casting micro-alloyed construction steel. Such defects were not seen on hot band when rolling slabs from...

At Primetals Technologies Brazil Ltda. Rio de Janeiro Santa Cruz Workshop we electroplate mold coppers for continuous casting by tank plating. Tank plating submerges the copper in the bath of the plating solution. This is the most common method of plating and is applicable for both broad-face and narrow-face copper plates. Mold copper plates have a decisive impact on the product quality as...

For decades most radiometric sensors have been based on photomultiplier tube technology. Berthold Technologies GmbH has lately implemented the new silicon photomultiplier technology in radiometric sensors for mould level measurement. By multiple silicon based photomultiplier chips in an array, numerous benefits have be achieved. The strong temperature dependency of the silicon...

There are chances of ambient air getting aspirated into the upper nozzle/ladle shroud region that connects ladle to a tundish due to the presence of a negative pressure zone. Inert-gas shrouding is carried out in these regions with the idea to create a protective blanket all around the above-mentioned refractory structures. However, on the downside, some Argon gas bubbles get aspirated into...

A level of steel in the tundish is changing during sequential continuous casting. The most significant decrease of the steel level occurs when replacing ladles. It is generally known that if the height of steel level in the tundish drops below a certain critical level, it may generate vortexes over the nozzles and as a consequence entrainment of tundish slag into individual casting strands can...

Strand guide rollers in continuous casters are crucial components for an optimal process for the production of high-quality steel grades. The properties of these rollers greatly influence the quality of the slab produced. The most commonly used designs so far have been the axle roller and the solid roller. Through an intensive exchange of experience with the caster manager of continuous...

Process stability during continuous casting is an essential criterion for the production of high quality stainless steels. In particular the meniscus, which is the most sensitive zone of the whole strand, has to be in a steady shape and position. As the liquid core of the strand acts like a hydraulic hose, each radial movement of the strand shell is inducing a feedback on the mold level...

Steel meniscus fluctuations and level deformations in CC mold are one cause of the defect occurrence on slabs and later on coils. Slivers, which are one of the most costly defects observed on coils, are partly due to slag entrapment in CC mold. Actually, a strongly deformed meniscus and sudden meniscus level fluctuations favor the slag carry-away into the steel and entrapment of slag droplets...

Non-metallic inclusion have a strong impact on the final product quality in steel production. Thus, inclusion removal from the melt is an important aspect of achieving the intended steel properties. In continuous casters the tundish can be utilized to enhance inclusion removal. One method to promote inclusion removal within the tundish is the installation of an argon bubble...

When continuous casting rolls are in operation, the load pressure and temperature changes from the top segment at the point of continuous contact to the horizontal zone. During this process, rolls must withstand the following phenomena:  Elevated temperature  Intensive water spray cooling  High slab contact pressure  Fatigue due to cyclic thermal and mechanical stresses  ...

The paper will explain how to successfully implement a robotic solution from the initial idea to a working industrial solution. Primetals Technologies could call upon the past 10 years of experience in installation of Robot solutions in the harsh environment of steelmaking plants - the so called LiquiRob. To enhance an existing shroud manipulation system, the idea to connect the shroud with a...

The modern continuous casting machine is a highly complex mechatronic system where utmost precision has to be reached to ensure high product quality while the equipment has to be designed to withstand the harsh environmental conditions. These two requirements alone would make things difficult, but additionally the lowest operation costs have to be achieved to survive under highly competitive...

Summary (200 to 300 words) should be concise and contain all sufficient information for a fair assessment: An essential part in the continuous casting process is the mould oscillation, crucial for flawless mould lubrication and final surface quality. Oscillation parameters, such as stroke and frequency need to be adapted to the casting speed, steel grades, casting modes etc. The first...

In order to improve operational safety and at the same time process stability and product quality, new technologies have been developed and implemented in Continuous Casting to eliminate the use of hydraulics in the casting platform area. This paper outlines the developments and technical solutions in continuous casting for hydraulic-free casting platform operation for e.g.: • Accurate...

The prerequisites for using an Energy Collector (E-CO) for the recuperation of radiant heat are red-hot material at temperatures exceeding 750 degrees Celsius over a long roller table. The slabs are transported to the heat exchangers via the roller table. There, depending on their surface temperature, they radiate between 45 and 70 kW thermal energy per square meter. The heat exchangers take...

With the increasing demand on casting process stability, product quality and output, there is a strong need for advanced mould monitoring techniques. Key subjects are meniscus stability, mould fluid flow and mould temperatures. This paper describes the development and application of Fiber Bragg Gratings (FBG) for mould temperature monitoring on a broad face at a slab caster of Tata Steel...

Against the background of the decisive role of heat transfer in the continuous casting mould for product quality a CFD model was developed, verified with industrial trials and applied for the adjustment of the cooling conditions in the mould. The numerical model included melt flow and solidification as well as a completely resolved cooling system, i.e. copper mould walls and cooling water...

Corner crack is one of the main defects which affects continuous casting slabs. It downgrades slab surface quality and requires further scarfing which is costly and time consuming. Chamfer mold technology is a new mold design which may reduce corner cracks occurrence during continuous casting process. Conventional continuous slab casting uses rectangular shape mold with 90°corners. Chamfer...

Primetals Technologies provides proper technological solutions for the revamp of long product casters, and the most recent examples for successful implementation at Feralpi (EFS) and at Abinsk (AEMZ) are presented in this paper, showing the qualitative results that can be achieved within shortest project execution time. Elbe-Stahlwerke Feralpi (EFS) in Riesa, Germany awarded PT with a...

A new advanced radiometric sensor for mould level measurement in closed stream casting has been designed by SMS Concast. The unique feature is to determine both the real position of the steel meniscus and the thickness of the lubricating powder on top. Compared to the conventional instrumentation this refined setup overcomes the limitation of measuring only a single intermediate level with no...

Following increasing market demand for thicker plates, work was carried out to increase the cast thickness of a 0.16% C – 1.5% Mn plate grade, microalloyed with Niobium, from 225 mm to 305 mm. This paper describes a surface quality issue encountered during the change and steps taken to investigate the cause. Specifically, fine transverse cracks were observed at around 150 to 300 mm in from the...

In order to decrease the mould level fluctuation the casting parameters such as casting speed, mould powder and oscillation type have to be optimized. The general full factorial design of experiments were successfully carried out two times. In these experiments two different mould powder and sinusoidal/non-sinusoidal oscillation types from high to low casting speeds were investigated in-situ...

The key impact of mold powders on steel quality is well-recognized. However, manual feeding is still a widespread practice, leading to powder thickness variations, meniscus instability and poor process reproducibility, with negative effects on steel quality. Dedicated technologies for automated powder feeding are therefore crucial. A new mold powder diffuser with built-in optical sensor for...

Atypical secondary oscillation marks (SOM), and related transversal surface cracks, have been detected on the billet surface between two consecutive primary oscillation marks, when casting with abnormal oscillation settings in Curve Continuous Casting (CCC). The study of the obtained near surface solidification microstructure under this conditions have shown similarities with the...

Based on the numerical simulation and industrial experiment research, the retention characteristics of the ultra-low carbon steel slab corner shape in the hot rolling process and its influence on the edge defects are analyzed. Numerical calculation results show that, the chamfered face changes to be circle arc during hot rolling process. The uniformity of stress distribution is improved. The...

The black and white band defects of type 304 stainless steel on the hot and cold rolled coils are chronic. The black and white band defects are subsurface defects and can be found chrome carbide in the defects on the surface of the hot rolled coils. The cause of chrome carbide is an increase of carbon near the oscillation mark on the subsurface of slab due to carbuizing of mold powder during...

In actual steel continuous casting process, the spraying water in secondary cooling zone always distributes non-uniformly, especially across the width direction of the steel bloom/billet. However, it is generally assumed that the cooling pattern of secondary cooling zone is uniform in many traditional heat transfer models, which will surely result in obvious calculation errors. In this paper,...

The key technologies and development process for high speed casting technology were described by the study on the No.3 high-efficient slab caster of Shougang Jingtang Company. Within more than one year of technical research, some measures were applied to solve problems such as insufficient mold cooling, mold level fluctuation, and slab bulging. As a result, the casting speed successfully...

For the casting of Nb-mikroalloyed steels with C- content >0.09 mass-% the transverse crack formation on the slab surface is a big problem. The production practice at voestalpine shows that these crack formation is dependent on the content of microlalloyed elements like Nb, Al, B, V and N -content. Higher content of micro alloyed element causes more crack formation. In the present work,...

Summary (200 to 300 words) should be concise and contain all sufficient information for a fair assessment: In recent times developments of casting technology for long products are heading increasingly in the direction of high speed casting resulting in significantly increased heat load in the mould. Heat loads exceeding the capabilities of a standard mould tube lead to overheating of the...

Summary (200 to 300 words) should be concise and contain all sufficient information for a fair assessment: The market requires that steelmakers of high quality products assure and are able to give proof that their steel is defect free. In a caster, in order to discard portions of defective steel, it is necessary to identify their locations and crop them out. Wasting portions of good steel...

Previous studies have shown that the application of mechanical strain over a long period of time can facilitate precipitation of microalloyed particles. Hence there is a need to clarify whether casting with a multiple straightening scheme rather than a bending/unbending design could be detrimental for the quality of CC of microalloyed steel grades, due to the time extension of the deformation...

Cast-Endless rolling route for deformed bars is establishing as a reliable process for higher and higher productivity at lower operational costs thanks to the energy saving advantages. In IIC-Egyptian Steel Plant it has been started up a new turn-key steel plant designed for the world’s highest productivity of 75 t/h in an endless single line. Design capacity has been already exceeded...

High requirements on the slab qualities necessitate optimized casting processes and high precise analytical methods. Determination of macro segregation using optical spark emission spectroscopy make possible fine adjustment of soft reduction in order to acquire optimal isotropic properties of hot rolled products. To account for the individual quality characteristics of main steel grade,...

Today’s and future steel industry challenges demand sustainability for the production of long products and aims for lowest energy consumption. Further the trend for the installation of small production units utilizing resources from a local area to serve the rolled products in local markets needs a very efficient process directly linking casting and rolling process. Ideally, this process...

An improvement of surface quality of casting slab increases productivity of steel. The slab surface sometimes has transverse cracks along a grain boundary when the slab is bended and/or unbended around the transformation temperature from austenite phase to ferrite one. This defect is mainly caused by film-like ferrite and carbide and/or nitride precipitations around the grain boundary and...

HADEED commitment to improve steel quality is emphasized by the installation of Dynamic Soft Reduction (DSR) system at slab casters. The system purpose is to improve steel internal quality in terms of reduced internal cracks and centerline segregation, which will lead to higher quality of hot rolled coils. A comparative study conducted to evaluate the influence of dynamic soft reduction system...

Micro alloy steels are an important product within the automotive, energy, pipeline and structural segments. Superior continuous cast bloom quality is critical in order to achieve the high quality strength and toughness balance required for today’s demanding bar, plate and sheet applications. Continuous casting parameters, such as super heat, mold level fluctuation, heat transfer, fine grain...

The digital transformation achieves a structural change in automation – a transformation of process automation into a new and more efficient structure. Today's hierarchical automation pyramid is replaced by a flat structure of intelligent, flexible and autonomous units. It is important that the metal industry makes an active contribution to implement digitalization in their production plants...

WinLink is a pioneering technology from Primetals Technologies that allows both endless and semi-endless production of long products from liquid steel without interruption. The solution directly links a high-speed billet caster to a high availability rolling mill by using an advanced induction heating unit instead of conventional billet reheating furnace. GPH Ispat Ltd. in Chittagong /...

For many years SMS group modernizes various continuous casters and equips them with state of the art technology. The scope, proven by some 500 revamps worldwide, ranges from small optimizations right up to far-reaching changes of the continuous casters. The concrete measures are defined according to the customer’s objectives: the improvement of the slab quality, the expansion of the product...

The core of CONSAFE is a safe and performant mould level sensor for open stream casting. The patented sensor array includes four thermocouples which are easily integrated into the wall of the copper mould tube. A state-of-the-art controller (ms-cycle) runs the CONSAFE algorithm. It evaluates the dynamic transients of the monitored temperatures and reliably converts the sensor readings into the...

The In-Situ Material Characterization–Bending (IMC-B) test is a new laboratory method to evaluate the susceptibility of steel towards transverse crack formation in the continuous casting process. Samples are cast under near process conditions, cooled to bending temperature in a controlled way and finally bent in a 3-point bending test with a deflection of only a few millimeters, according to...

Within the scope of the collaborative research center SFB 761 “steel ab initio” the castability of high manganese steel grades with varying aluminum and manganese contents via the continuous casting (CC) route is under investigation. Within the current research the high temperature embrittlement of these high manganese steels in the temperature range of 700 °C – Tliq has been examined, using...

The demands for AHSS have gradually increased due to their ability to reduce vehicle weight as a means to save energy, and to reduce the environmental impact. However, the successful design of AHSS often require the addition of large amounts of alloying elements such as aluminum, which make it difficult to cast sound slabs without surface defects. When casting high aluminum AHSS, due to the...

In the current work, an one-quarter scale water model was established to investigate the effect of bubbles and slags on the fluid flow in a slab continuous casting mold. The variation of the profile of the top surface and the critical condition for the entrainment of slags were studied using a high-speed camera. A Particle Image Velocimetry (PIV) was used to measure the fluid flow velocity and...

High Al steel containing Al more than a percent has been recently developed which increases specific strength significantly by forming very fine FeAl intermetallic compounds in the matrix. For a successful commercial production, continuous casting is prerequisite, but the high Al content causes serious trouble for the casting practice due to strong reaction between Al and SiO2 in mold flux. ...

POSCO CEM® process can continuously produce coils without cutting before the finishing mill. Material balance with high throughput between the casting and rolling is essential to achieve this process. Throughput of CEM® has boasted a world-class level in the casting area. This was achieved with a high-speed casting technology and increased slab thickness up to 100 mm. Recently, many steel...

TWIP (Twining Induced Plasticity) steel is very promising AHSS (Advanced High Strength Steel) grade owing to its superior toughness and ductility. Recently it has attracted the interest of the automotive and steelmaking industries, as the need for reducing weight to provide better fuel efficiency is of paramount importance with the gradual depletion of fuel resources. But these steels are...

The hot ductility trough experimental data of as melting samples has been quite well adjusted by the quantity of MnS precipitated in the solid, the MnS secondary precipitation. A numerical model has been developed to calculate the MnS primary precipitation during solidification, secondary precipitation in the solid during the ulterior cooling. The model calculated MnS secondary precipitation...

Slag entrainment is a challenging problem to control during continuous casting process. From fluid dynamics viewpoint, it mainly occurs due to (I) the instability of the fluids interfaces at the top of the mold and (II) vortex formation around the sub-merged entry nozzle (SEN). Both mechanisms are complex phenomena involving surface instability, vortex interactions with the metal-slag-air...

The thin solidifying shell in the meniscus region of continuous caster deforms due to severe contraction of steel during solidification for near peritectic composition of steel and there is potential risk of cracking and in the extreme cases, breakout of shell. The main purpose of the present study was to contribute an improved understanding of peritectic transformation through high...

Variation across different length scales of phase evolution during solidification of steel define the final properties of the cast slab. Various multi-phase models by Ludwig et al [1] and Beckerman [2] for modelling of columnar / equiaxed solidification microstructures in alloys exist in literature. In today’s world of high quality steel, understanding the dependence of the...

A Molten mold flux technology so called, POCAST process has been newly used to enhance the slab quality of Ultra Low Carbn Steel(0.001~0.002 C%). Due to the thicker slag layer and higher temperature of meniscus, POCAST technology can influence in many ways; shorten the hook length, decreased C-pickup on the slab surface, less inclusion within the slab, enhancing the slab lubrication and etc.....

In continuous casting of ferritic stainless steel electromagnetic stirring (EMS) is a common approach to generate an equiaxed crystal zone as large as possible. The layout of the electromagnetic device directly affects the intended solidification structure in the strand. In order to predict this influence, SMS group has developed a numerical model to simulate the interaction between flow...

IDS is a thermodynamic-kinetic-empirical tool for solidification, microstructure and material properties of steels, which has been developed at Aalto University in Finland since 1984. IDS calculates phase fractions, phase transformations and several solidification, cooling and reheating related phenomena, including inclusions and precipitates from liquid state to room temperature and during...

Optimization of CaO-SiO2-CaF2 based flux in a continuous steel caster should be determined from the view point of dual viscous functions for minimizing slab surface defects - high viscosity enough to alleviate flux entrainment at mold top surface where shear rate is about 10 – 40 reciprocal second and low viscosity enough to maximize lubrication capability at oscillated mold wall region where...

Mold slag plays a very important role in continuous casting process. However, the understanding on the real behavior of the mold slag film in-between the steel shell and Cu mold is still not very clear in terms of controlling heat transfer and lubrication. The reason is the complexity of the slag film history along the mold and its coupling effect with the temperature and time. In this...

By the visual inspection of the hot slabs during casting it is possible to observe only major defects and only on the upper surface. So the inspection of cold slabs later is needed, especially if trials were made. And in practice inspection of all slabs is nearly impossible. So there was need for a tool to have images from the hot slabs during casting – for several purposes. A tool called...

The application of magnetohydrodynamics in the continuous casting of steel enables improved control of the quality of the strand. The most common applications are electromagnetic braking (EMBR) and electromagnetic stirring (EMS). The former slows the flow by applying a static magnetic field and thus improves the steel flow pattern, reduces the velocity and the turbulence of the flow, increases...

Coupled thermal and mechanical model of continuous casting of thin slabs produced at OMK CSP was further developed. The model is constructed in the ANSYS Mechanical APDL software. For the tapered funnel mold, thermal 3D and structural 2D task was formulated and solved. For the secondary cooling zone, both thermal and structural problems were set as 2D models. The model is shown to represent...

Automation in the hot storage yard is a difficult task in an interconnected environment where differently sized slabs with a wide range of follow-up destinations create a complex set of stacking rules. Slabs that are destined to move on to scarfing, trimming or warm holding need to be carefully arranged to stacks in order to avoid cracks or curved slabs. The constrained storage space and the...

At voestapine Stahl Linz two different mold powders are used for casting construction steel, where powder A forms significant larger slag rims than powder B. Their chemical compositions are very similar. The CaO/SiO2 ratio for powder A and B is 1.25 and 1.20 respectively. Additionally powder B contains 0.97 wt% MnO. For the clarification of this difference in performance the melting behavior...

Depending on the product or the material grade, conventional deburring machines, such as e. g. with rotating hammers are in many cases not capable to reliably or completely remove the burr from the edges and corners of a continuously cast product. Burr, however, is generated at the front and/or tail ends of a slab, bloom or billet as a result of torch cutting. Likewise, traverse grinding of...

Fluorine is a crucial component in mould fluxes with a concentration that may reach and in some cases exceed 10% in weight. Fluorine works primarily as a fluxer and chain breaker, its effects include lowering of surface tension, lowering of melting temperature and lowering of viscosity. However serious drawbacks come from use of raw materials containing this element, such as enhanced corrosion...

These days the combination and utilization of the advanced numerical simulation techniques with the regulation algorithms is become the common standard in the industry production. In this paper the 3D macro solidification model for continuous casting process and original fuzzy logic regulator is described. The regulator was created in the focus on surface slab quality improvement. The macro...

High-Al steels attract wide attention in the automobile industry owing to their excellent combination of high strength and superior formability. The reaction between Al in the liquid steel and SiO2 in lime-silica-based mould fluxes during the continuous casting of these steels causes chemical compositional changes in the mould flux, subsequently affecting the surface quality of slabs. In order...

Fully coupled thermo-mechanical finite element models were developed, also casting and soft reduction tests were carried out in an industry casting machine, to investigate the formation mechanism of one kind of typical inter-dendritic crack around triangular zone in slab casting process, applying soft reduction technology. The effect of soft reduction amount distribution design combined with...

General Information Slab Milling According to today's state of the art, the continuous casting process is almost entirely used for the production of flat steel material. In the manufacturing process for high-quality rolled products, the requirement especially on the surface quality and homogeneity of slabs has increased significantly in recent years due to the quality and price pressure. A...

Hot tearing is a regular defect that affects slab internal soundness. Hot tears form at the end of solidification, typically between 0.8 and 1 solid fraction, when steel exhibits low ductility but can be subjected to stresses which generate deformation. Excessive deformation will then open the dendritic structure and lead to cracks. New steel grades which are currently under development are...

Keywords: mould powder, fluoride free, heat transfer Abstract: When casting steel grades in the peritectic range it is critical to control the heat transfer from the steel shell in order to minimise longitudinal crack defects. In practice, horizontal heat flux is predominantly controlled by mould flux crystallinity. Cuspidine (3CaO.2SiO2.CaF2) is seen as the most preferable crystal phase...

Thin slab casting and rolling processes are well known and are permanently developed further since their introduction end of last century. Finding the optimum constellation to also economically operate and fully load the rolling mill part lead to different concepts, combining up to three casting strands to be fed into one rolling mill section. These different concepts are based on complex...

Monolithic isostatically pressed ceramics for flow-control applications usually consist of 20-30wt% of carbon plus refractory components. The main role of the carbon is to create a thermal shock resistant microstructure in the ceramic body. One negative side effect is it’s relatively high thermal conductivity which can lead to temperature losses of the liquid metal on its transfer from...

Producers of cast products are in duty to their customers to document the inner quality of the product. The ultrasound measuring is a widely known and well-established technique for non-destructive analysis of the inside of a material used in medicine and many other fields. Every women being pregnant appreciates that very much being able to get the situation of her unborn baby without any big...

Start of cast breakouts are a major concern for process reliability in the Tata Steel thin slab caster at IJmuiden, The Netherlands. Splashes at start of cast, emerging from the upper ports of the four port SEN, may cause weak spots in the solidifying shell, leading to sticker type breakouts. A threefold approach to investigate splashing behaviour has been followed, linking thermocouple data,...

One of the challenges when casting new high-alloyed steel grades, is to cope with segregation, leading to central segregation. The central segregation is influenced by the cast structure (which in turn depends on the alloy content of the steel melt, on superheat, on secondary cooling) and the machine state. There are several possibilities to perform an assessment of the macrosegregation...

We present an experimental study about the influence of magnetic stirring in the submerged entry nozzle (SEN) for continuous casting of round blooms performed at the mini-LIMMCAST facility at Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The experimental setup consists of a round mould with an inner diameter of 80 mm made of acrylic glass, representing a mould used in industry. A magnetic...

This papers presents an experimental and numerical analysis of the redistribution of the alloy chemical components, the grain solidification structure and likelihood of porosity formation in continuous casting of stainless steel. An experimental setup consisting of a rectangular ingot was developed to mimic the solidification conditions of a continuous cast slab. The amount of energy extracted...

In the recent study from the authors [1] a criterion is established for the near wall mesh treatment for simulating submerged entry nozzle (SEN) flows for the industrial applications. Fulfilling the criterion is found to crucial when it concerns a possible flow detachment (see Fig. 1) inside the continuous casting (CC) SEN. A numerical model, based on the RANS approach, matches the...

Technical solutions and design optimization for better quality, increased productivity and yield have been continuously introduced and implemented in Tata Steel thin slab plant located in Jamshedpur – India to further improve competitive edge in the current steel market. Extensive advanced computer simulations and physical simulations have been conducted to determine the different parameters...

**Quality fist is our slogan in EZZ Steel (EZDK), Egypt, so controlling all casting parameters is very important and interesting topic to deal with. EZDK faced a repeated LFC during production different types of steel grade; many actions were taken to decrease defected coils due to LFC appearance. The actions taken LFC were dived as follows: 1. Process parameters control by casting with...

Macro-segregation in the center of CC strands can lead to problems during downstream treatment and application of steel. Particularly high carbon or high manganese steel grades are susceptible to form those high concentration areas concerning their pronounced heterogeneous structure during final solidification. Many investigations have carried-out during the past decades to determine those...

To improve the productivity of continuous casting, the adoption of thin slab caster is being steadily increased. Due to high speed casting of thin slab caster, the optimized deign for SEN becomes precondition for stable operation in casting. Design technology for SEN has been improved through fluid flow analysis and thermal stress analysis by computer simulation and water model...

In 2014 Fuxin Special Steel Co. Ltd., Taiwan, has successfully commissioned a steelworks for manufacturing stainless steel slabs at the Zhangzhou location in the Chinese Fujian Province. The new construction project comprises a special steel plant, a vertical liquid bending continuous slab caster, environmental facilities for gas cleaning and energy recovery and the complete X-Pact® electric...

The dynamic soft reduction is more and more applied in bloom casting to improve internal soundness for long products, aiming to achieve consistent and reliable results in reducing V-shape segregation and central porosity. Soft Reduction for Round sections represents a new step ahead in CCM development, requiring a new concept for application to be effective, considering the “shape factor” of...

Research of Clogging in Continuous Casting Nozzles at KU Leuven M. Guo1*, Y. Vermeulen2, Rob Dekkers3, X. Guo4, Patrick Wollants1, and Bart Blanpain1 1Dept. of Materials Engineering, KU Leuven, 3001 Heverlee, Belgium 2 3 ROCKWOOL B.V. Industrieweg 15, Postbus 1160,The Netherlands 4Dept. of Mater. Sci. & Eng., TU Delft Mekelweg 2, 2628 CD Delft, The Netherlands *Corresponding...

The steel quality produced in a modern high productivity continuous caster is greatly increased by a flow modifier controlling the fluid flow in the mold. To achieve a controlled flow in the mold, to stabilize and to improve casting operation, the third generation FC Mold (FC Mold G3) has been mounted in the molds. This electromagnetic equipment combines the conventional double-level DC...

Nozzle clogging during steel pouring in the continuous casting process is a long-standing problem for Al-killed steels. During casting the flow rate of liquid steel through the nozzle is reduced due to the nozzle clogging, which leads to serious operational problems. Even though the ladle slide gate is fully open, the molten steel flow rate can hardly meet the demand of the tundish, causing...

In the objective to improve the internal soundness of the as-cast round format 400mm in ArcelorMittal Ostrava, a strong collaboration has been launched between the team of the steel plant and the R&D centre of Gandrange, specialized in long products. In this framework, a focus has been made on forging grades, which have shown a high sensitivity to the occurrence of central cracks and...

A major contributor to the quality of continuous cast steel is the flow structure in the mold. In case of slab casting, only the double-roll flow structure is expected to result in optimum quality steel, while other flow structures, like the single-roll or the unstable flow-structure, are generally associated with defects like slag entrainment or non-metallic inclusions. As countermeasures,...

Ultra low C (ULC) steel is one of major products of high quality steel in a number of steelmakers. Slab of the ULC steel is produced by continuous casting process in order to maximize process efficiency. Ti is one of important alloying elements of the ULC steel, in order to secure good formability of the steel, as it is used for outer panels of automobile. It has been a long problem that...

This paper provides an overview about latest realized solution for the bloom continuous casters on the example of a heavy section bow type caster, which is equipped with latest technological packages. Bars and wires, which are rolled out of the blooms, serve as primary material for engine and gearbox parts for Hyundai Motors Group. The caster is equipped with latest mold-level control and...

In 2016 a new 5-strand bloom caster was installed and successfully commissioned by Inteco melting and casting technologies GmbH at Jiangsu Shagang, Shagang Group (CN). The CCM is designed to cast section size 300 x 390mm on a 9m vertical bending-unbending machine equipped with latest SBQ-Technology. Besides other features, a tundish design with optimised liquid steel flow distribution, large...

In some cases, the precipitation of CaS around CaO-Al2O3 inclusions are observed in hot coil, even though it is not found in CC slab. The purpose of this study is to investigate S solubility in solid CaO-Al2O3 at various temperatures and clarify the mechanism of this phenomenon. For the experiment, first, the mixture of the reagent of CaO, Al2O3, CaS at a given composition was charged in...

The paper shows the long time trial of edge type of the electromagnetic VUHZ Mold Level Measuring System (MLM System) on Thin Slab Caster equipped with Electro Magnetic Brake (EMBR). Trial was realized in Rizhao China on Primetals ESP (Endless Steel Plant). Three MLM systems (X-ray, electromagnetic edge and suspended types) simultaneously were used for measurement of the steel level in the...

A new vertical caster for special steel grades was started up at Zhongyuan Special Steel Co., Ltd., in Jiyuan, China in June 2015. The 2-strand vertical round bloom continuous caster has a capacity of up to 370,000 metric tons per year, which enables Zhongyuan to produce additional high-quality steel grades, since the company only had an ingot casting plant for the production of mainly steel...

High clean steels have been widely employed as automotive parts. However, the spinel inclusion, which is formed during the ladle refining process, has potential causes of nozzle clogging as well as of defects in products. Furthermore, the liquid oxide inclusion in the steel melt can be transformed to spinel during casting process. Hence, it is crucial to predict the inclusion evolution during...

Demands on high profits and low costs in steelmaking industries are increasing and increasing recently as a result of strong global competition. The continuous casting process has been a good solution until now because of a high yield, energy saving, and omission of blooming process. But there remains to be solved the problem of how to cast an extra large section size strand and high-alloy...

SMS group has extended its product portfolio to include the new Micro CSP® concept, at the heart of which is the vertical liquid bending type Micro CSP® caster, which is designed for the annual production of approx. 500,000–750,000 t low and medium carbon steel. The idea behind this development was to limit the system to essential equipment only, while simultaneously ensuring stable and...

We have investigated lamination defects (slivers) on hot rolled coils of Ca-treated steel for microstructure and composition using optical and scanning electron microscopy combined with microanalysis (SEM/EDS). The goal was to identify possible origins for the observed defects which contain a complex assemblage of phases, such as different types of calcium aluminates (CA, CA2, CA6), melilite...

Danieli sets a new benchmark in continuous casting for largest round sections, after revamping of the CC3 machine in ABS plant (Italy). The startup in Huaigang (PR China) and Baosteel (PR China) as well as new orders of CCM in XiWang and revamping in YongGang confirm the constant market trend in increasing round section sizes for large radius CCM, endorsing the Danieli leadership in this...

Since pilot slab caster was operted in 2003 at POSCO, many casting tests were performed in this caster. Because this facility with a heat size of 23 tons is nearly half scale of the actual caster, advanced casting technologies have beed developed and applied in commercial caster. One of these technologies is high-speed casting. Design concepts of segment and cooling sytem, operation...

The mold flux is the most important thing for the lubrication between the mold and initial solidification shell in continuous casting process. However, in the process, the mold slag generated by the mold flux is entrained into molten steel and brings about the surface defects of IF steel. Generally, in order to reduce the entrainment of the mold slag, continuous casting plants have tried to...

Summary (200 to 300 words) should be concise and contain all sufficient information for a fair assessment: In recent years, Continuous Casting Machines for big round sections have found worldwide interest and many plants have been installed and commissioned. A significant driving force behind this development is the replacement of ingot casting with a more economic process; at the same time...

Abstract: Mold heat transfer is important to mold life, surface quality, breakouts and many other aspects of the steel continuous-casting process. Based on a series of related investigation, the mold cooling process on continuous casting slab of high-carbon steel (wC>1.5%) was investigated. Thermodynamic calculation has been carried out on a high-carbon steel by means of Thermo-Calc program....

Oscillation marks (OMs) can be classified into depression OMs and hook-like OMs, near which subsurface hook structures appear in ultra-low-carbon steel of continuous casting slabs. In the current study, the hooks of whole-leaf type, truncated type, re-solidified type and double-hook type were observed, and bubbles were found below hooks, indicating that hooks could capture the floating...

Abstract China’s first twin-roll strip casting demonstration industrial plant (NBS Project) with strip width of 1340 mm was built in 2014 by Baosteel in Ningbo, China. After a year of commissioning, the demo plant was put into stable casting and rolling production in 2015. The longest continuous casting time reached 4h and a thickness of 0.9mm ultra-thin carbon steel strip was produced...

As grain refinement can bring the substantial improvement of mechanical properties of as-cast and further rolled materials by reduction of segregation during solidification. Many studies, therefore, have been reported on grain refinement of as-cast structure by formation of inclusions based on so-called Oxide Metallurgy. However, there are also many problems in Oxide Metallurgy in terms of...

Segment Casting (SC) is a novel casting technology which combines the technologies and benefits of continuous casting and ingot casting, without limitations to steel grades to be produced. The bloom is vertically cast to a defined length and subsequently treated in-situ with various technologies until final solidification is completed. The key technologies are the combination of - A...

Rice husk ash on the molten slag is usually composed of solid powder layer, sintered powder layer and interface between the molten slag and sintered powder layer in continuous casting tundish. Because the complicated reaction at the molten slag-sintered powder interface has not been well understood, we investigated the effect of rice husk ash on the reoxidation of molten steel as well as on...

The direct strip casting process has attracted attention as a near net shape technologies. BAOSTEEL GROUP CORPORATION and Primetals Technologies Japan, Ltd. have jointly developed technologies for the direct strip casting process of carbon steel. The demo plant for the direct strip casting process, with 800 mm diameter and 1340 mm long casting rolls, was installed in China and its operation...

Continuous casting with bow type as well as vertical machines achieves high productivity and yield at high casting speeds. Nevertheless the speed is limited by metallurgical machine length and required cooling rates to achieve continuous production. This high cooling rates cause pronounced radial orientation of the crystallization front in the strand. Thus particularly at special high alloyed...