Kobe Works Research Articles

Straightening Technology of Round Bars Using 2-roll Rotary Straightener

In order to improve the productivity and quality of round bar products, the finishing area of the round bar mill was revamped at Kobe Works, Kobe Steel Ltd. in 2011. Various pieces of equipment were newly installed, such as a high-speed rotary straightener, a magnetic leakage flux testing system and an ultrasonic testing system. Among them, the straightener was the key device and was expected to soon be in actual operation. In addition, it was necessary for this straightener to correct the round bar shape of the product, widening its diameter from 17 to 80mm more than the conventional one. To decide the proper setting of the roll gap, the roll skew angle and the rotation speed of the top and bottom rolls of the straightener, a simple 3-point bending model was applied, and the inside of the working straightener was observed by an infrared camera. This paper describes the synergistic effect of the above mentioned three straightening factors and the applied result of these straightening conditions in actual operation.

Technology Transfer on the Wooden Carriage Design and Construction between Japan and England in 1870's

At the start of Japanese National Railway's transport from Tokyo to Yokohama in Oct. 1872, 58 wooden carriages were imported from England. In May 1874, another national railway started transport from Osaka to Kobe and 83 wooden carriages were prepared. In Feb. 1877, the latter national railway was extent to Kyoto. In Meiji era of Japan, wooden carriage construction had been continued by using imported parts and materials at Shinbashi and Kobe works of Japanese National Railway. It called as 'The Imperial Government Railway of Japan (IGRJ)'. Trainers of these works were all English railway engineers in 1880's. Many wooden carriages were designed and constructed by Japanese trainees. They took imported wooden carriages for model. Same methods were taken by other main Japanese private railway's works as Nippon Railway, Sanyo Railway and so on. Some private rolling stock builders started their business in Meiji era. There were high level Japanese technology and skill which accumulated through wooden furniture making and ship construction down to Edo era in the carriage construction. In this report, results on the technology transfer between English-made and home-made wooden carriage were explained. For the purpose of our research, we used famous rolling stock documents 'JAPANESE RAILWAYS LOCOMOTIVES CARRIAGES WAGONS AND CROSSINGS &C. &C. 1893' called as 'Blue-Printings'. These documents were compiled by an English railway engineer Mr. Francis Henry Trevithick (1850-1931) with Japanese railway officers in Meiji era.

S2001-2-3 ウオルター・マッカーシー・スミスと鉄道寮神戸工場製の第一号御料車について(機械技術史・工学史(2),社会変革を技術で廻す機械工学)

S2001-2-3 ウオルター・マッカーシー・スミスと鉄道寮神戸工場製の第一号御料車について(機械技術史・工学史(2),社会変革を技術で廻す機械工学)

Development of a Continuous Desiliconization Process in the Hot Metal Runner of a Blast Furnace

Abstract An efficient continuous desiliconization process equipped with a mechanical stirrer in a hot metal runner was newly developed. The facility was installed during the revamping of No.3 blast furnace at Kobe Works, and the commercial operation started up successfully in January 2008. Before the installation of the commercial facility, the reaction behaviour was investigated under various experimental conditions for the application of a mechanical stirring method to continuous desiliconization treatment in the hot metal runner. Hot metal experiments at laboratory scale showed that the stirring intensity was an important factor for the process performance, and the mechanical stirring method was available for the improvement of reaction efficiency. As a result of plant tests, it was confirmed that a higher oxygen efficiency of desiliconization was achieved by the combination of runner arrangement and mechanical stirrer compared with the conventional injection of the desiliconizing agent. According to the reaction analysis of continuous desiliconization in the hot metal runner using the semi‐batch reaction model, it was estimated that the average slag‐metal residence time in the reaction region is improved due to an increased entrainment of foamed slag into the stirred metal bath in the mechanical stirring method, and therefore, it leads to a high desiliconization efficiency. Based on the experimental results, the equipment specifications and the runner design for this process were determined.

207 ウオルター・マッカーシー・スミスと鉄道寮神戸工場における初の木製客車製造(機械技術史・工学史)

207 ウオルター・マッカーシー・スミスと鉄道寮神戸工場における初の木製客車製造(機械技術史・工学史)

Japan's First Domestically Mass-Produced Class 230 2-4-2 Tank Engine and Technology/Skill Transfer on Steam Locomotive Construction from the United Kingdom

The Class 860 2-4-2 tank engine, which was the first steam engine domestically built in Japan, was constructed in 1893 by engineers at the Kobe Works of the Imperial Government Railway of Japan (IGRJ) under the supervision of a British locomotive superintendent. Ten years later, in 1903, production began on the first mass-produced steam engine in Japan at the Osaka Locomotive Manufacturing Company (Kisha Seizo Kaisha), the first Japanese private locomotive manufacturing company founded by Masaru INOUE (former director of IGRJ) in 1896. It was a noteworthy technological feat that a total of 41 2-4-2 tank engines of the Class 230 were manufactured during the Meiji period. In this report, we make a technological comparison of steam locomotive design and construction between the Class 230 tank engine and the standard-type engine which was imported at that time from the United Kingdom. In addition, technology/skill transfer on steam locomotive construction and the originality of Japanese engineers and workers will be discussed. The contents of this report are as follows. 1) Introduction, 2) Standard-type engines imported during the Meiji era, 3) Establishment of Osaka Locomotive Manufacturing Company (Osaka Kisha Seizo Kaisha) and early manufacturing of steam engines, 4) Technology transfer from the U.K., and innovations by Japanese engineers.

Relation to the Steam Locomotives Imported from the United Kingdom at the dawn of the Imperial Government Railway of Japan; IGRJ and the First Domestically-built Steam Engine No.221 in 1893 by the Kobe Works of IGRJ

Steam locomotives, that were imported from the United Kingdom at the time of railway construction commencement of Japan in early stages of Meiji period, will be explained, and also the genealogy from the imported steam locomotives to the first domestically-built steam locomotive No.221 (later, renamed class 860) manufactured in 1893 by Kobe Works, Imperial Govement Railway of Japan; IGRJ will be described from the viewpoint of the foreign technology transfer.

Improvement of billet surface quality by ultra-high-frequency electromagnetic casting

An experiment of continuous casting with ultra-high frequency electromagnetic field was carried out at No. 4 commercial caster at Kobe Works. It was confirmed that the durability of a slit mould was sufficient for long casting, and meniscus level was controlled precisely enough for stable casting by the level control technology using the inductance change in the magnetic system. The improvement of billet surface quality and the lubrication between the mould and the solidified shell are discussed.

310 わが国鉄道創業期の蒸気機関車について : イギリス製テンダ式蒸気機関車(機械技術史・工学史)

For the beginning of Osaka-Kobe railway transportation in 1874, two English-made steam locomotives (Nos.5000,5001) were imported by the Imperial Government Railway of Japan:IGRJ. These were the first tender steam locomotives in Japan, and they were made in 1871 at the Sharp Stewart & Co., Manchester. In 1876, IGRJ Kobe Works remodeled two tender steam locomotives Nos.7010,7011 for freight-train use into Nos.5100,5101 tender locomotives for passenger-carrying use. These were the first remodelling works in Japan by Japanese railway engineers only. It is a pity that these valuable steam locomotives were taken to pieces. In this report, 1)History of these locomotives and their builders, 2) Examination of two different types of valve gear mechanism for Nos.5100,5101 locomotives, are descrived.

Fully automatic magnetic-particle inspection system for square billets

In Kobe Works, an automatic Magnetic-Particle Method was developed using image processing technology. In order to improve the detection rale of this system for short surface flaws, various kinds of cameras were evaluated for their basic characteristics, and CCD cameras were selected and employed in the system. In addition, the algorithm of pattern recognition was improved to detect shorter flaws. As a result of these changes, it is now possible to detect short flaws which arce deeper than 0.3 mm and longer than 10 mm. and the surface quality of final products is improved.

Development of the hard reduction method in the No. 3 bloom caster at Kobe works, Kobe Steel

The center segregation of continuously cast blooms has to be improved, users demands being more and more severe concerning equiaxed crystal proliferation and filling observed in the conventional casting.

High purity CO gas separation by pressure swing adsorption

A pressure swing adsorption (PSA) process with a single stage for recovering high purity CO was developed with an original chemical adsorbent that adsorbs CO selectively. A pilot test was made to optimize the process and confirm the stability of the adsorbent. A first commercial plant was constructed at the Kakogawa Works of Kobe Steel in March 1989. Subsequently, a second commercial plant was constructed at the Kobe Works of Kobe Steel in October 1990. The two plants have been producing high purity CO stably and consistently.

Improvement in the production of high grade wire rods and bars by using a billet caster

Kobe works is equipped with two casters : a bloom caster and a billet caster. For improving the product quality at the billet caster, some techniques are developed : inclusions decreasing, surface defects decreasing, center segregation reduction. A precise control of the temperature in tundish has been carried out. As a result, a new target is to produce higher grade steels.

神戸製鉄所における転炉を中心とした精錬プロセスの改善

神戸製鉄所における転炉を中心とした精錬プロセスの改善

Production of Low-SiO2 Iron Ore Sinter and Blast Furnace Operation at Kobe Works, Kobe Steel, Ltd.

Sintering technology that lowers the SiO2 content from 5.6% down to 4.9% has been achieved at Kobe Works on the basis of the following concept: the desirable structure of quasi-particles for low-SiO2 sinter consists of limonite ores as the nucleus and fine ores with low SiO2 and Al2O3 contents as adhering particles. In addition, the basicity and MgO content of sinter should be increased. As a result, the reducibility and high-temperature properties of sinter have been improved, though the RDI value of sinter increased. The use of low-SiO2 sinter in the Kobe No. 3 Blast Furnace has brought about the increase in overall permeability due to an increase in permeability at the lower part of the furnace, in spite of a decrease in the upper part. This increase has contributed to an appreciable increase in the ore/coke ratio and rate of pulverized coal injection.

A Computer Control System of the Reheating Furnace for Continuous Cast Bloom

Since August 1981, a new computer system has been applied to the reheating furnace for the continuous cast bloom at Kobe Works. This system has been developed for the purpose of saving energy, quality control and automatic operation. The newly designed 5-zoned furnace is equipped with independently-operated walking beams at each zone and blooms are normally hot-charged. In the newly developed system, an optimal heating pattern is determined by on-line calculation in order to minimize total fuel consumption. The technique of minimizing fuel consumption is realized by means of the linear programming method. The bloom temperature is calculated by using the two-dimentional heat transfer equation, and is controlled to coincide with the heating pattern by regulating the setting values of the furnace temperature. Operating results show that fuel consumption is reduced to 600 x 103 KJ/T which is 10% less than that of manual operation. The cast blooms are transported fully automatically from the continuous caster, charged into the furnace, heated up and extracted.

Measuring Methods for Lining Erosion of the Blast Furnace

A new fine multiple thermocouple sensor (FMT sensor) for the measurement of refractory lining erosion of a blast furnace is presented. In the newly developed sensor, the temperature sensing parts of several sheathed thermocouples are arranged longitudinally parallel. They are accommodated in an external sheathing tube in such a manner that these thermocouples are prevented from coming into mutual contact by means of insulating refractory materials. The sensor can simultaneously measure the temperature variations at several positions in the refractory lining.A method of analyzing the FMT signals (The Trigger Response Method) has also been developed for calculating the remaining thickness of refractory lining in the shaft of a blast furnace by analyzing the time-delay occurring in the propagation of temperature variations in the lining. By applying this method to 19 months of field testing in the shaft of No. 1 Blast Furnace of Kobe Works, it was possible to estimate the extent of erosion of the refractory lining within an error tolerance of less than 5%.A method of analyzing the temperature distribution in the lining (The Profile Coefficient Method) has also been developed for estimating the profile of lining erosion in the hearth by introducing the Profile Coefficient defined by the solution of the finite element method in which the boundary conditions are determined indirectly by using measured temperatures in the lining. This method was applied in the No. 1 Blast Furnace of KakogawaWorks and its practicability was confirmed when its estimation corresponded to those taken by the dissection studies.

Advanced technology of process design for high-quality bar and wire-rod production

AbstractUsers of rod and bar products, particularly the automobile industry, are making increasingly severe demands on the manufacturers for higher-quality materials. Manufacturers have responded by improving production technology and specializing. Kobe Steet Ltd, which has a long tradition ofproducing high-quality rod and bar, has been aware of this situation and has modernized its production processes. The aim has been improve the quality of the material at the input stage rather than at the billet or final-product stages. The authors describe the background to the modernization of the Kobe Works.