• International Journal of Korean Welding Society
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• v.4 no.1
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• pp.1-9
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• 2004

Continuously welded tracks, first introduced on train lines, are being used increasingly in Europe. And the different arc welding methods are only used on minor lines, private tracks and in the manufacturing of switches and crossings. Mobile flash butt welding belongs the future in rail welding on side if new tracks have to be erected. The following contribution reviews the processes available, usual test methods for welded rail joints and various applications.

• Journal of Welding and Joining
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• v.8 no.1
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• pp.54-61
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• 1990

A pilot production is made to the high carbon Cr-Ti alloy rail steels with slight quantity of Cr & Ti added to the eutectoid carbon steel. As a part of weldability of these alloy steels, SH-CCT diagram for welding is first applied to the high carbon Cr-ti alloy rail steel with 0.1wt% Ti. The microstructure, which will be appeared at the HAZ of Enclosed-arc welding of this alloy rail seel, is a single phase of pearlite. As a result of this, it shows that the welding condition of Enclosed-arc welding applied to this alloy rail steel is a good condition.

• Proceedings of the KWS Conference
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• 1993.05a
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• pp.38-40
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• 1993

• Proceedings of the KSR Conference
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• 2000.11a
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• pp.396-401
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• 2000

There are three examples of noise reduction test by rail welding. One of them is tested at electric car running area and another is tested at expansion joint and long welded rail and the third is tested at open deck bridge. We can know from the result that the noise reduction effect of rail welding is very different to the type of track and the car. The condition of the test has some differences, but it may be useful reference of noise reduction.

• Journal of Welding and Joining
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• v.30 no.5
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• pp.40-45
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• 2012

Nowadays in Republic of Korea, whole amount of the thermite welding powder for rail joinning is dependent on import. However the demand of the thermite welding powder would be enlarge because some constructing high-speed train and city metro projects are currently in progress. In addition this is the main reason why we should develop the thermite welding powder, domestically. This study is focused on utilizing the recyclable materials like Al powders from cans and iron oxide scales from wire rods as the main components of the thermite welding powder. By minimizing Al content in weld zone by controlling the mixing ratio of the Al powder in the thermite welding powder, the excessive dissolution of the Si and Mn components came from the Al powders could be controled. The tensile strength of welding zone in welded rail was 740 MPa, with that the developed thermite welding powder.

• Tribology and Lubricants
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• v.15 no.2
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• pp.178-183
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• 1999

This paper presents friction and wear related results of thermite and gas pressure welded rails under various environmental contact conditions. A welded rail which was fabricated by thermite welding and gas pressure one has been tested over full range of test conditions in a pin-on-disk wear testing machine. The results show that the friction coefficient and wear rates of a welded rail are heavily dependent on the contact pressures and sliding environments for two welding methods such as thermite and gas pressure weldings.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.06a
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• pp.345-353
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• 1999

This paper presents friction and wear related results of thermite and gas pressure welded rails under various environmental contact conditions. A welded rail which is manufactured by thermite welding and gas pressure one has been tested rail full range of test conditions in a pin-on-disk wear testing machine. The results show that the friction coefficient and wear rates of a welded rail are heavily dependent on the contact pressures and sliding environments for two welding methods such as thermite and gas pressure weldings.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.684-691
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• 2010

Rail is one of major track components for train service, it should be provided in the condition of flat and smooth driving aspect. Therefore, it is inevitable that there would be the field welding to integrate on CWR(Continuous Welded Rail) removing rail joint in these days. It is high chance to be some rail surface irregularity due to the limitation on the status of work condition If a high speed train runs on the rail surface irregularity in the welding part, big impact load comes to pass on that, so track irregularity cycle is reduced, therefore track maintenance cost can be increased. this paper has analyzed wheel load variation according to removing the rail surface irregularity using portable grinding machine in the high speed line. The result measured before and after in the field is decreased about 9.26% on the wheel load variation.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.7
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• pp.551-558
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• 2016

Reduction of welding residual stress is very important in the railway industry, but calculating its distribution in structures is difficult because welding residual stress formation is influenced by various parameters. In this study, we developed a finite element model for simulating the repair welding process to recover a surface damaged rail, and conducted a series of parametric studies while varying the cooling rate and the duration of post weld heat treatment (PWHT) to find the best conditions for reducing welding residual stress level. This paper presents a three-dimensional model of the repair welding process considering the phase transformation effect implemented by the ABAQUS user subroutine, and the results of parametric studies with various cooling rates and PWHT durations. We found that heat treatment significantly reduced the residual stress on the upper rail by about 170 MPa.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.512-518
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• 2008

The importance of modern electronic devices is gradually increased and, the requirement of the safe and reliable earthing and bonding for protection of the electronic devices is consequently absolute. The electrical continuity and physical strength of the bonding work in rail signal and impedance bonding is also one of the important issues. The thermit welding for earth cable connection and rail bonding work proposed hereunder is an effectively applicable in many fields of rail industries.