Station naming deals announced
Runaway Rail Car Kicked Loose by Teen Hits New York Station
Škoda unveils its second tram for the Chinese market
Wabtec to buy Faiveley Transport for US$1·8bn
Constantine tram extension contract
Channel Tunnel: '2,000 migrants' tried to enter
Ottawa urban rail gets federal funding
UK and Italian operators order Vossloh locomotives
First Great Western and Eversholt sign Hitachi AT300 train contract
Tanzania, Rwanda and Burundi invite interest in DIKKM railway
The rail – one of the most valuable track assets
Existing rail maintenance strategies and programmes must be adapted in order to successfully implement a new integrated rail maintenance approach. High performance rail milling offers the chance to introduce a predictive maintenance programme. This can be achieved by combining process simulations with well-defined resultant rail surface conditions and advanced rail surface characterisation technologies. Consequently, introducing an integrated rail maintenance approach will lead to significantly increased performance levels of one of the most valuable track assets – the rail.
The cutter heads
Rail milling is a spark- and dust-free rotational cutting process where material is cut out of the rail surface in the form of ‘chips’. Each cutter head consists of 140 to 220 carbide inserts, depending on its diameter. Heat from the milling process is mostly transferred to the metal chips, which are then collected on board the milling machine to be recycled after the process is completed. The low heat generated by the milling process prevents ‘bluing’ or the generation of martensite, an unwanted by-product of heat-related material transformation at the surface of the rail. The shape of the high precision cutter head determines the resulting shape of the rail profile. Any pre-defined rail profile can be produced by the milling process. Multiple profiles can be produced by changing the cutter heads which can be done quickly, depending on the number of milling units on the milling machine.
The maintenance activities
There are two ways to perform rail maintenance activities. A preventive maintenance strategy can help to keep the rail surface free of any defects. However, once Rolling Contact Fatigue (RCF) has formed, a regenerative rail maintenance strategy should be used to completely remove those defects and prevent premature rail replacement. The milling process allows for low to high metal removal rates per pass, dependent on the size of the machine. Therefore, this process can be used for all types of maintenance strategies. Typical milling machines are equipped with one, two or three cutter heads per rail, depending on the application scenario. Furthermore, Linsinger’s milling machines can also be used to treat switches and crossings. In urban environments, the resultant periodic cutting structure on the rail surface can cause some unwanted temporary noise effects. To mitigate this, milling machines are equipped with a polishing unit. This unit consists of a completely enclosed longitudinal grinding wheel with a slight offset angle that polishes the running surface of the rail to create a noise optimised, high quality surface finish. No metal removal is carried out during in this process.
A variety of rail maintenance activities – especially rail milling – can be introduced as part of an integrated track maintenance approach. Several examples from satisfied customers around the world confirm that rail milling is a successful complementary solution to prevent premature rail replacement and to economically treat mainline track, switches and crossings, resulting in a significant extension of rail life.
This article first appeared on www.globalrailwayreview.com
About this website
Railpage version 3.10.0.0037
All logos and trademarks in this site are property of their respective owner. The comments are property of their posters, all the rest is © 2003-2020 Interactive Omnimedia Pty Ltd.
You can syndicate our news using one of the RSS feeds.