STEEL & METALLURGY :: Abstract for May 2008 Issue

View of May' 2008 Issue
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Achieving Productivity of Blast Furnace 2.5 and Beyond - JSPL’s Experience
By Shamshad Shaik, Amitabh Sarcar, S.Ghosh, Jindal Steel and Power Limited, Raigarh(C.G).

ABSTRACT
The process of iron making in blast furnace has undergone considerable change to meet the requirement of high productivity at lower fuel consumption, low operating cost and in an environment friendly conditions. Low fuel rate favors high productivities, low slag volumes and good quality of hot metal. In the case of Jindal Steel and Power Ltd., Raigarh the burden consists of 68-74 % sinter. Slag volume has been reduced from 360 to 300kg/thm, productivity raised from 1.9-2.5 THM/m3/day and the coke rate has been brought down from 610-400 Kg/THM. High oxygen enrichment of the blast facilitated increased pulverized coal injection and improved thermal balance of the furnace thereby increasing gas utilization. The coke and sinter quality used in the blast furnace controls permeability of the furnace with increased PCI rates from 30-120 kg/THM.
This paper deals with the steps taken on optimization of the burden distribution through a Bell Less Rotary Charging Unit, high oxygen enrichment, increased coal injection and careful monitoring of coke and sinter quality to reduce the coke rate and increase the productivity.

Advanced Equipment for High-Performance Casters
By Siemens-VAI

ABSTRACT
A number of technological packages are now available to help steel companies increase continuous caster productivity and flexibility, raise product quality and lower operating and maintenance costs.
For slab casters these include efficient cassette-type molds for an optimum strand shell growth, hydraulic width change for variable casting widths and hydraulic mold oscillation for enhanced strand surface quality. Furthermore, dynamic soft reduction solutions are outlined to enable superior internal slab quality.
Bloom casters are also benefiting from high-performance molds, hydraulic oscillation and—now being introduced — dynamic soft reduction.

Chemical Roll Coaters: A simple and ecological passivation technology
By Giorgio Garlatti, Marco Ravera, Strip Processing Department, Tenova Strip Processing, Milan, Italy

ABSTRACT
The passivation of galvanized or cold-rolled strips in galvanizing or painting lines can be carried out for different purposes, the most important one being an increase in the corrosion resistance of the material. Three different passivation/conversion processes can be distinguished:

The thickening of the natural oxide film;

The production or precipitation of phosphates, chromates or chrome-free heavy metals;

The application of an organic synthetic polymeric film.

This article describes the passivation/conversion of strip surface with devices called Chemical Roll Coaters, which apply a metered amount of chemical product to both sides of the strip by means of applicator rolls.
The use of Chemical Roll Coaters turns out to be effective for important economical, ecological and technical advantages

Endless Rolling in Bar Mills
By Our New Bureau

ABSTRACT
By utilizing flash welding equipment to join billet ends, bar and wire rod mills can be made to operate without billet gaps, thereby improving product quality and productivity while reducing production costs. This paper describes the equipment necessary for the endless rolling of billets with a special focus on the welding process and quality aspects.

Steel Market And Trade outlook For The US In 2008
By David Phelps, President, American Institute for International Steel

ABSTRACT
The US steel market and US economy seem to contain a series of contradictions. While the banking crisis has created the environment for a recession that many believe is already here, the domestic steel industry has been raising prices, producing at full capacity and for some products, putting customers on allocation. Many sectors of the economy are weak, autos, housing and white goods and if one asks steel executives from mills or service centers, they seem mostly to agree that demand is not all that strong, with of course some exceptions, such as in energy related markets.
The steel market in 2007 was weaker than in 2006 to be sure, with imports down by 26.6%, shipments down by 3.1% and the overall market down by 10%. However, the steel market was not as weak as the data suggest due to unusually high inventories at the beginning of 2007, which turned out to be a year of inventory correction which took essentially all year. Imports, however, experienced a merciless decline through the year, battered by the weak dollar, higher prices in many international markets and freight rates that escalated to levels unheard of in the past.