Specially designed trains, operating at a constant speed of 700 meters per hour, machine the existing track profile. By removing millimetres of metal from the damaged surface, the track is restored to its original condition.
This application requires specialised equipment to achieve optimum results, such as ‘train machine tools’ designed to carry dynamic rail milling cutters and inserts.
At Dormer Pramet, we work in partnership with several high-speed milling machine manufacturers to delivery key projects around the world. One of these included the milling of three different rail profiles for a customer in the Netherlands.
Our 600mm diameter dynamic rail milling cutter was able to machine the profiles without having to change the inserts. This is hugely beneficial as it saves both time and costs, reducing the number of tool change-overs.
The development of new rail technology is constantly taking place and modifications are needed on both sides to optimize the match between the machine and cutting tool. We have adapted our dynamic milling range to fit various sizes, from 300mm to 900mm, with plans to develop a 1,400mm diameter version in the future.
At present, there are more than 50 dynamic rail milling cutters being used in several countries, including the Netherlands, Germany and Poland. Wheel returning
Another example where we provide support to the railway segment is in wheel returning. This too can see standard tools being modified to become custom-made specials, unique to the requirement of the application.
A customer in Philadelphia, USA, was having issues with its previous LNMT inserts as they were not able to break chips during a wheel turning operation. The resultant long, continuous swarf congested the area around the workpiece. The process to clear the chips is not only time consuming but can also be hazardous.
We put forward our standard LNMT inserts, but during tests, found these too did not break the chips as required. Following further feedback and discussions with the customer, we were able to make two key changes to the insert.
First, we added a corner radius chip breaker to relieve some of the pressure on the tool, then tailored the geometry and design of the insert to prevent nesting at high depths of cut.
The customer wanted to make one pass, so the LNMT insert needed to be able to achieve a staggering .700” (18mm) depth of cut at the first attempt. Following the changes, our insert was put in for further testing.
Not only did this new design fix the chip control problem, but it consistently outperformed all other inserts tested. The customer now orders its inserts from Dormer Pramet.
For more information regarding Dormer Pramet’s railway assortment contact your local sales office.