Technical Report No.52 (2009)
Shinagawa Technical Report
What I have in Mind "In a Time of Upheaval"
Managing Director N. TSUKAMOTO;
SHINAGAWA's Approach in the Field of Functional Refractories and Mold Powder to Meeting High-speed Operation Requirements in the Continuous Casting of Steel Slabs
E. IIDA, M. OGATA, T. OMOTO and Y. IWAMOTO
High-speed casting (2.0-3.0m/min) of steel slabs causes increased fluctuation of the molten steel surface and decreased thickness of the solidifying shell in the mold.
Hence submerged entry nozzle (SEN) and mold powder have been improved to meet the casting condition.
In order to prevent breakout, powder consumption, melting speed, viscosity at low temperature and the peeling properties of the slag film are taken into consideration when designing mold powder.
In addition, new mold powder series, which satisfies both mild cooling at meniscus and sufficient heat removal in the mold, have been developed for the high-speed casting of middle carbon steel grades.
As for SEN, annular-step SEN and mogul SEN are suitable for the high-speed casting because they supply symmetric outlet flows and suppresses penetration of inclusions deep in the mold.
Mold Powder Development for Improving LC and ULC Steel Sheet Quality
J. ITO, Y. IWAMOTO, T. OMOTO, T. SUZUKI, J. GILMORE and B. HE
Mold powder is one of the most important materials for achieving stable casting operation and good steel qualities.
Development of better mold powders is becoming more important in improving casting technologies.
Main defects in low carbon (LC) steel and ultra low carbon (ULC) steel are inclusions and gas bubbles.
New higher viscosity mold powders were developed and used in casting these grades.
Casting operation was stable without any problems and the defects ratios of cold rolled steel sheets were improved by approximately 40% by using new higher viscosity mold powders.
Development of Completely Backward Inclined Lining for BOF
We would like to present a "Completely Backward Inclined Lining" which is an optimum lining for BOFs. There are 36 possible lining combinations for the combined lower knuckle, barrel and cone sections. By making full use of the latest structural analysis technology (FEM), all cases were studied.
As a result, we can expect that brick fractures and gaps between bricks which cause drop off will not occur, if backward inclined or round-corner linings are applied for the lower knuckle section and backward inclined linings are applied for the barrel and cone sections.
Technical Information on Products
The GAIREX Series of Low Carbon MgO-C Bricks
M. KAKIHARA, H. TADA and E. IIDA
MgO-C bricks have been used in BOF, RH and electric arc furnaces. In some applications, a decrease in carbon content is required to improve durability and solve environment problems.
However, the spalling resistance of MgO-C brick is greatly decreased by decreasing the carbon content.
The innovation of thin layers composed of organic compound around magnesia grains to absorb the thermal expansion of magnesia and the application of special pitch powders have been studied in order to improve the poor spalling resistance in low carbon MgO-C bricks. As a result, low carbon MgO-C bricks with the high spalling resistance called "GAIREX" have been developed. This paper is about the GAIREX series of low carbon MgO-C bricks.
Quick Hardening Hot Casting Repair Mixes for BOF
H. SASAKI, K. KOMATSUBARA and T. KOYAMA
In this study, we examined the possibility of developing quicker hardening and developed high-performance new quick hardening hot casting repair mixes.
Multifunctional Unshaped Refractory "POLYVALENT"
H. SASAKI, H. YAMAJI, M. TAKIKAWA and M. NAMBA
In steel plants and incinerators, unshaped refractories called "General-purpose Products" have been used in relatively-low damage parts which don't touch molten steel directly.
We aimed at improving workability which is an important characteristic of the general-purpose products. We developed a new revolutionary general-purpose product brand called "POLYVALENT" which can be installed by all installation methods such as gunning, troweling, casting and pumping by only adjusting water content.
In this paper, we introduce the product line-up and characteristics of POLYVALENT
Dust Reducing Technology of Unshaped Refractories
H. SASAKI, H. YAMAJI, M. TAKIKAWA and M. NAMBA
Recently, unshaped refractories are widely used in the steel and non-iron industries.
We have developed a new dust reducing type of unshaped refractories for improvement of the working environment.
The new products have little dust compared with conventional products, and provide good working conditions in the installation field for gunning and so on.
These new products are being used by many customers with good reputations.
Development of Plastic Gunning Installation Method and Materials
Y. SASAI and H. SASAKI
Plastic refractories are clay bonded materials in which fireclay is used as a plastic raw material, and are applied by ramming or by gunning with compressed air.
Our company has developed and markets plastic gunning materials and methods.
Plastic gunning reduces the period required for refractory work in comparison with ramming, but its adhesion rate was inferior to dry and wet gunning, and it had the serious drawback that curing contraction after installation was larger than with ramming.
Therefore, various improvements were made in the equipment in order to improve the adhesion rate and workability, and materials with low curing contraction were developed. The results are described in this report.
Practical Use of SST Equipment
K. YAMAMOTO, M. OSADA and A. TAKATA
Shinagawa has developed a new generation of slide gate valve equipment called 'SST' for flow control at steel plants. It is a very simple mechanism because of an automatic surface load system. SV equipment of the 'SST' type is in practical use.
This paper presents details of this new generation of SV equipment.
Large-sized Zirconia Ultra-high Temperature Furnace (ZRF:Zircofurnace)
Y. SASAI and J. OKUHARA
The zirconia furnace is an electric furnace which enables heating to 2000°C in an oxidizing atmosphere.
Our company is the only maker which has developed and markets practical zirconia furnace technologies.
However, because the usable working dimensions of the zirconia furnace are small (φ25mm), its application had been limited to laboratory tests.
In recent years, there have been numerous needs for large-sized furnaces for use in calcining of products, but still issues remained in relation to temperature measurement accuracy and melting of the platinum wire terminal.
Therefore, this company carried out various improvements, resulting in the development of higher-reliability furnaces. The developed technology is introduced in this report.
Environmental Improvement of Tunnel Kilns by Switching to LNG
S. FUJITANI and K. KOSAKA
Environmental measures such as CO2 reduction are big issues which should be considered globally.
The fuel used for our tunnel kilns was converted from LPG to LNG as an environmental measure in the basic refractories plant in our Okayama works.
Quantitative Analysis of Carbon Affecting Purity of Silicon Carbide Raw Materials and Boron Carbide Raw Materials
K. IKEGAMI, S. NOBUHARA and S. UCHIDA
In determining the purity of silicon carbide raw materials and boron carbide raw materials, quantitative analysis of the free carbon contained in the raw materials is necessary.
Free carbon could not be analyzed with sufficient accuracy with the conventional combustion and infrared absorption method.
Therefore, a new method was developed by improving the wet chemical oxidation and coulometric titration method so as to enable application to these raw materials.
As a result, it has become possible to analyze the free carbon content in the raw materials with high accuracy.
By applying this method, it has also become possible to separate and analyze carbonates from products in which carbonates and free carbon exist in a mixed state.
Comparison of Refractory Situation in Japan and China
n recent years, the trend of China's industries has attracted attention across the world with China's rapid economic progress.
The Technical Association of Refractories, Japan printed a special issue of Taikabutsu in April, 2005 on China's refractory industry situation, where China's refractory production, raw materials and so on were introduced in detail.
In this report, we will contrast the refractory industry situation of Japan and China and show some differences between the two countries in accordance with information including data from the past 2-3 years.
Finally, we will discuss future trends.
Information on Products of Associated Companies
Shinagawa Refractories Australasia Pty. Ltd. "The Development of Shotcrete Materials for Australian Industries"
P. EDWARDS, M. HERRING, Dr.L. HONG, H. SASAKI and Y. HAMAZAKI
Shotcrete has been developed and used widely within many industries.
There is a strong demand for introducing shotcrete in the Australian industries such as Alumina, Mineral Processing and Cement due to its advantages in installation, particularly speed and environmental considerations.
However the exacting demands in these industries has resulted in the "off the shelf" materials being unable to meet the requirements.
Shinagawa Refractories Australasia have developed new materials to meet to each customers specification and have been successfully installed in trials.
Shinagawa Fine Ceramics Co., Ltd. "Development of Arrestor Using Ceramics and Mo Electrode"
Sanyo Electronic Industries Co., Ltd. T. YAMANE
A novel molybdenum arrestor was successfully developed.
The molybdenum arrestor has the advantage of high-speed-response.
Adoption of this product has achieved satisfactory results in trouble spots.
Shinagawa Chemicals Co., Ltd. "Dry Cleaning and Purification of Solvents"
H. MINAMIZONO and T. MITSUBOSHI
Dry cleaning uses organic solvents to remove soil and stains from clothes.
The removed soils are contained in the solvents.
It is necessary to refine the used solvents, because dry cleaning uses solvents repeatedly hundreds of times.
Cleaning agents purify dirty solvents by adsorbent action.
Our company brought the cleaning agent "P.ace", which uses allophane as a raw material to the market in 1965. "P.ace" has been received favorably as an excellent product for adsorbing soil in solvents efficiently since its introduction.