perkeretaapian.com

Dunia Perkeretaapian ada di depan Anda

Columnists

Bordeaux Tramway

Posted by mikeefos August 11, 2011 Bordeaux ...

The path to exemplary ...

The path to exemplary working efficiency ...

Freight train from ...

Freight train from Zhenzhou to Europe container ...

LRT Palembang ...

Senin, 13 Agu 2018 08:46 WIB LRT Palembang ...

High-Speed Rail

High-speed rail (HSR) is a type of passenger rail ...

Features

Move Over Metro

Move Over MetroBy Troy Turner ...

futuristic australian train

Futuristic Australian Train ...

Guillemins TGV Railway ...

Guillemins TGV Railway ...

"The Future Tramway" designed ...

"The Future Tramway" designed ...

Flash-butt Welding

The welding process is in principle a regulated electric short circuit with the two rail ends functioning as D.C. poles. The high current produces an arc between the rail ends, the two rail cross-sections are heated to melting temperature due to the high input of current.

During the following upset stroke the rails are pressed together under high pressure causing the ends to coalesce. The upset metal is trimmed off immediately after the upset stroke.

The result is an  accurate weld without filler metal with a very small heat-affected zone and a more or less consistent progression of the hardening process with a favourable crystal-line structure.

Mobile flash butt welding2http://www.railsystem.net/wp-content/uploads/2015/06/Mobile-flash-butt-welding2-300x140.png 300w" sizes="(max-width: 608px) 100vw, 608px" width="608" height="284">

flash butt weldinghttp://www.railsystem.net/wp-content/uploads/2015/06/flash-butt-welding-300x140.jpg 300w" sizes="(max-width: 608px) 100vw, 608px" width="608" height="284">


Preparing the weld – the slight inclination

Due to the shape of the rail, there is an irregular distribution of material over the cross-section. Due to the effect of the electric current during flash-butt welding the rail is heated up to melting temperature. Consequently the rail does not cool down uniformly over the entire cross-section. The rail foot and the rail base cool down first.

Animation_of_flashing_operation_in_Flash_Butt_Welding

Because the largest proportion of material is in the rail head, this cools down far more slowly. The natural consequence is a depression of the rail in the area of the welded joint.

However, this result would have very negative effects on the track geometry and the operational safety. For this reason, a slight upward inclination of the two rail ends is performed, adapted to the respective rail profile, so that an ideal position of the rail is achieved when the weld has cooled down.


Flash Butt Welding & Alumino Thermic Welding

a) Alumino Thermic Welding

– Strength of AT joint is app. only 56% of parent rail.
– More prone to corrosion
– High failure rate.
– Poor Quality of Weld.

b) Flash Butt Welding

– Strength of FB joint is almost equal to parent rail.
– Less prone to corrosion
– Failure rate < 10 %.
– Excellent Quality of Weld. The defects like porosity, inclusions and lack of fusion are eliminated.


Mobile Flash butt welding Machine

– It is rail cum road machine that can be driven to site.
– The mobile Flash butt welding machines are either built in Standard railway vehicle or as containerized units.
– In case of m/c built on Railway Vehicle the welding head is Positioned between the bogies and can be lowered for welding in running track..
– The containerized units can be used for welding in track or on cess on the other hand the standard vehicle machine can be used only on running line.
– New machine is fully computerized.
– Once the welding head is in position, the entire process is carried out automatically at the push of button.


Welding Parameters

– Welding current,
– Upset force Pressure,
– Displacement,
– Welding time,
– Programmed identification and setting details.


Procedure Approval Tests

1) Weld Trimming
2) Weld alignment
3) Weld appearance.
4) Non-Destructive testing
5) Bend testing
6) Fatigue Testing
7) Macro Examination
8) Hardness testing
9) Statements of the result and procedures.
10) Maintenance of the records


Sources; Today published by Plasser & Theurer, indianrailways.gov.in


Related Standard;  BS EN 14587-2 – Railway applications. Track. Flash butt welding of rails.


Videos; 

Top video picks

normal-view3

Justin Bieber sings at UD...

normal-view3

Sport Science: (11/17/11)...

normal-view3

World Sport TV: Roger Federer...

normal-view3

Shooting in Shark River Hills...

New templates

Who's Online

Kami memiliki 22 guests dan tidak ada anggota yang online

Lokasi

  • Bandung, Jawa Barat, Indonesia
  • Alamat email ini dilindungi dari robot spam. Anda memerlukan Javascript yang aktif untuk melihatnya.
  • 08112291110 

New templates

Selamat datang di perkeretaapian.com, Siapa kami ?

Who's Online

Kami memiliki 22 guests dan tidak ada anggota yang online

Statistics

OS:  
Windows
PHP:  
5.3.24
MySQLi:  
5.5.32
Waktu:  
22:55
Cache:  
Nonaktif
GZip:  
Nonaktif
Pengunjung:  
21
Artikel:  
526

For using special positions

Special positions are: sticky_left, sticky_right, notice, tool_bottom. You can use them for any module type. For using this, please go to Module Manager and config your module to your desired position.

These can be disable by:

  • Go to Administrator » Template Manager » Your_Template » Tab: Advanced » Use special positions » select: No for all special positions
  • Go to Administrator » Module magager » Your_Module(by postion: sticky_left/ sticky_right/ notice/ tool_bottom) » Status: Unpublished for that module

For customize module in special position

The solution is used Module Class Suffix. You can customize button, module content follow Module Class Suffix

E.g. Module Class Suffix: bg-white @bullhorn then:
- Class of button is 'ico-bullhorn'. If without @... the default is 'icon-pushpin'
- Class of module is 'bg-white'

Live chat

Live chat

To help us serve you better, please provide some information before we begin your chat.

Template Settings

Color

For each color, the params below will be given default values
Blue Oranges Red

Body

Background Color
Text Color

Header

Background Color

Spotlight3

Background Color

Spotlight4

Background Color

Spotlight5

Background Color

Footer

Select menu
Google Font
Body Font-size
Body Font-family
Direction