Rails perfectly maintained High Speed Grinding High Performance Milling Flexis System
Grinding, milling and switch maintenance The right strategy for every track High Speed Grinding (HSG) pages 4 9 Milling and High Performance Milling (HPM) pages 10 13 Flexis System for perfect switch maintenance pages 14 15 Head checks Time / load tons Prevention using HSG Corrugations and slip waves The type of defect and its severity in the rail decide the strategy. Vossloh s experts develop a tailormade maintenance strategy based on a track s individual characteristics using methods such as High Speed Grinding (HSG), milling and switch maintenance. While preventive grinding is particularly suitable for keeping near new and wellmaintained tracks in good condition and correcting minor damage at the same time, rail milling strives to correct existing defects found deeper in the rail. Switches require special care; and here Vossloh has developed its holistic Flexis System. Damage depth Wear limit / service life Damage progression without maintenance Milling Illustration of strategies to combat rail wear and its impact on service life Without maintenance, rails have to be replaced far too frequently at great expense and with considerable effort. If maintenance is only performed irregularly, rail defects continue to worsen until milling becomes the only remedy. Conventional rail grinding is only effective if carried out Conventional rail grinding Squats Advanced rail defects Breakouts very slowly, i.e. when the track is closed, and is inadequate in most cases. High Speed Grinding, on the other hand, achieves the best results in terms of rail quality, route availability and life cycle costs. 2 3
High Speed Grinding High Speed Grinding (HSG) Prevents rail defects Reduces noise Brings down costs 100 % longer Deutsche Bahn, the Technical University of Berlin and others confirm: HSG doubles the rail s service life! ADVANTAGES Rails ground without track closures HSG-2 reaches speeds of up to 80 km/h HSG-city reaches operating speeds of up to 60 km/h Longer rail service life Significant noise reduction No need to disassemble points and signaling equipment Minimal sparks or dust Completely suitable for tunnels No overheating or gouging Optimum grinding results without grooves No restrictions at level crossings or sound absorbers Transverse profile is optimized Smoothing of the rail s longitudinal profile Regular grinding prevents damage! It s like brushing your teeth: regular care prevents wear and damage. Preventive rail maintenance using High Speed Grinding (HSG) applies this principle to rails, preventing rolling contact damage and corrugation and ensuring long-lasting quality and low costs. Regular grinding with the HSG-2 grinding vehicle and HSG-city can verifiably double the rail s service life! Thanks to HSG, grinder burn as fertile ground for rail defects is no longer possible. And what s more: the procedure is also recommended as an effective and affordable noise reduction measure. High Speed Grinding is suitable for all railway systems from high-speed routes to city railway networks. Deployment can be flexibly adapted to the train timetable and all without closing or preparing the track! HSG-city (left) HSG-2 grinding train (below) * with the HSG-2 grinding train Here s how High Speed Grinding works Heavy traffic and high speeds lead to cracks (head checks) and other damage like squats in the wheel-rail contact zone. HSG remedies this problem. Its patented grinding technology comprises special abrasive wheels arranged at certain angles and turned passively by the vehicle s propulsion. These rotate as they pass over the rails and completely remove the damaged top layer. Three passes with the HSG train will remove a minimum of 0.1 mm of rail steel*, which reduces corrugation and slip waves and optimizes the longitudinal profile. The rail is smoothed while the dual dust extraction system captures almost all the grinding dust and sparks. TESTED AND ENDORSED Technical University in Berlin: In comparison with conventional methods, regular preventive grinding of the work-hardened rail surface reduces the life cycle costs of the heavily trafficked high-speed lines to 50 % and suburban routes to 61% respectively. DB Netz AG has compared two high-speed lines. The result: HSG is sustainably effective! High-speed rail line between Cologne and Frankfurt (No preventive work since commissioning) Technical service life Maximum damage Source: DB Netz AG 2013, Oliver Kraft High-speed rail line between Nuremberg and Ingolstadt (Preventive work since commissioning) Technical service life Maximum damage Set at an angle to the rail, the grinding wheels are pressed down hydraulically and grind very evenly Commissioned in 2002 Pronounced head check growth due to express traffic Corrective rail machining: Removal: 1.8mm every two years Costs: 12 Euros per meter (6 Euros per meter and year) Head checks not completely removed Service life ended by head checks and wear limit reached from 2010 on Expected service life of rails: 8 12 years Commissioned in 2006 Pronounced head check growth due to express traffic Corrective rail machining: Removal: 0.1mm 3 times a year (High Speed Grinding) Costs: 1 Euro per meter (3 Euros per meter and year) Head checks prevented End of service life and wear limit not expected to be reached before 2020 Expected service life of rails: 15 20 years 5
Hsg-2 and HSG-city Grinding train HSG-2 Grinding in heavy rail format at high speed HSG-city grinding machine Short routes in sync with the timetable HSG-2: fast, thorough and inexpensive With the HSG-2 High Speed Grinding train, Vossloh makes it possible for network operators to carry out rail maintenance within the timetable. This technology selectively removes only the work-hardened rail surface, thus preventing the formation of head checks and corrugation. The grinding pattern can be variably adjusted to optimize the rail s transverse profile as well and all this at an operating speed of up to 80 km an hour! The extraction technology collects the material removed and its dust bunkers have an impressive six-ton capacity. Work progress is precisely monitored and the results are documented. Thanks to its modular design, two HSG grinding trains can be coupled together into a high-performance twin version. TECHNICAL SPECIFICATIONS 96 grinding wheels Operating speed: 60 80 km/h Non-operational traveling speed up to 120 km/h Shift output: up to 100 km Rail roughness: Ra < 10 µm Process parameter documentation Reduces corrugation and slip waves Optimizes rail s longitudinal profile Recommended for machining noise-sensitive areas SUCCESS KNOWS NO BOUNDS HSG has been used in Germany since 2007, and also in Sweden, Denmark, the Netherlands, Switzerland and China. Here are some of the routes. Shanghai Beijing Cologne Frankfurt Nuremberg Erfurt Halle Leipzig Hamburg Hanover Amsterdam Rotterdam Brussels Stockholm Airport Stockholm Berlin Hanover Mainz Worms Nuremberg Munich Copenhagen suburban railway Conventional grinding machines km/h HSG-city was designed for suburban commuter networks, short main line routes, railway stations and special locations. At its heart is a grinding unit similar to the one used in the HSG-2: proven technology in a new dimension! With the HSG-city, Vossloh has the fastest grinding machine for metropolitan rail and short main line routes currently on the market. The maximum operating speed of 60 km per hour allows a workflow without track closures, so the HSG-city can be inserted directly into the railway operator s timetable. HSG-city can operate pushed and pulled, so it can be used with many different kinds of traction machines, e.g. road/rail vehicles. HSG-2 and HSG-city 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 Saves time and money and reduces noise TECHNICAL SPECIFICATIONS Grinding wheels: 24 Operating speed: 15 60 km/h Nonstop grinding capacity: 30 km Rail roughness: Ra < 10 µm Process parameter documentation Controlled remotely from the traction vehicle Required traction: minimum 170 kw, pulled or pushed Twin version: two machines can be coupled together SUCCESS KNOWS NO BOUNDS HSG-city is currently being used by many operators, e.g. the Rheinbahn in Dusseldorf, on the suburban railway system in Bremen, Beijing Metro and the Copenhagen Metro. 6 7
High Speed Grinding High Speed Grinding Here s when HSG is used Rails before, during and after HSG machining 1. Preventive grinding 4. Acoustic grinding Regular preventive grinding runs remove the rail s work-hardened and brittle surface. Not only does this prevent head checks from forming, it also removes corrugation and slip waves and considerably delays the need for repair work and rail replacements. The wheels rolling on the rails are a major source of rail noise. Optimizing the wheel-rail contact using High Speed Grinding minimizes corrugation and slip waves and reduces the acoustically relevant roughness of the rail. Consequently, traffic using the smoother rail generates significantly less rail noise. Various measurements have shown that HSG grinding demonstrably results in an acoustic improvement of up to 10 decibels. 2. New rail grinding Grinding new rails removes manufacturing-related defects of the rail and evens out the rail s transverse profile. New rail grinding (mill-scale grinding) is the initial machining of the rail in the factory or in the track bed after manufacturing or milling. This grinding delays the onset of rail damage. Machining is done either in the factory or in the track bed depending on the lengths used and the track-laying conditions. Machining the rails once they have been laid does have advantages, however, because any damage inflicted on site can be rectified and removed. 3. Grinding to remove slippery build-up High Speed Grinding is also effective in removing slippery films caused by the build-up of fallen leaves or air pollution. The resulting good grip when braking and accelerating serves to increase safety. IT S NOT WHISPER-QUIET WITHOUT QUIET RAILS Replacing grinding wheels NEW RAIL MACHINING Removes the decarbonized layer/mill scale Creates a uniform and continuous rail head profile Extends the machining intervals because the formation of defects is delayed Eliminates alignment errors in site-welds Grinding is an essential part of rail maintenance, but aggressive grinding reduces the effectiveness of the high-quality whisper brakes considerably and leads to long-term damage. HSG grinding protects both wheel and rail and mitigates noise by up to 10 db(a)*. +10 db(a)* * Data from the sonrail project results, Thron Aggressively ground rail with facets and heat damage 8 All the data gained from previous experience, e.g. with the Rheinbahn in Düsseldorf, indicate that preventive rail maintenance leads to audibly quieter rail traffic. HSG technology has also been designated by DB Netz AG as the official method for noise reduction, also for Besonders überwachtes Gleis (BüG), (tracks specially monitored in noise-sensitive areas). HSG grinding pattern immediately after grinding Smooth wheel (K, LL, disc brakes) Smooth wheel (K, LL, disc brakes) Rough rail (aggressively ground rail, corrugation forming) Smooth rail (ground using HSG, no corrugation) 9
Milling Rail Milling Here s how rails regain their profiles As it machines the rail head, the milling wheel completely re-profiles the rail Running edge High material removal rate to counter defects deep in the rail Reprofiling to the original condition ADVANTAGES Milling reaches far deeper into the rail than grinding and removes rail defects that are already well advanced. As a consequence, rail milling is primarily used in applications where conventional grinding is uneconomical. It can significantly delay the costly necessity of removing and replacing rails and extend a rail s life cycle considerably. High removal rate: Rail milling is a cutting process that removes deep flaws in a single pass. It is precisely controlled to within one tenth of a millimeter and capable of removing up to 3 mm of metal. Rail milling restores the rail to its original profile. The rail is given a new surface and thus the best possible basis for a long-term maintenance strategy. Milling optimizes the rail to the specifications in the relevant directives and reprofiles it using the following parameters. Defect depth Rail profile Rail inclination Track gauge After the milling process, the ideal scenario would be to switch to a preventive maintenance strategy (best case: High Speed Grinding). Minimizes costs over the long term Optimizes the rail s operational availability Postpones difficult and costly rail replacement works Extends the rail s service life and impacts extremely positively on rail life cycle costs RANGE OF APPLICATIONS RE-LAYING USED RAILS Track correction Machining heavy-rail routes for high-speed passenger traffic, freight and mixed use Removing longitudinal and transverse rail head defects Reducing rolling noise and wear Altering rail profiles Re-profiling Defect depth Time There are still places where, if rails are worn out on the running edge, they are taken up, rotated and re-laid a laborious process after which the only recourse is to replace the rails entirely. This procedure also involves the risk of existing defects continuing to worsen. Milling, on the other hand, will restore the rail surface and postpone the necessity of rail replacement much more effectively. The milling principle: remove deep defects in a single pass 10 11
milling Rail Milling Environmentally friendly and flexible High Performance Milling (HPM) The future of rail milling WE TURN A BIG WHEEL At the heart of the HPM machine is the milling wheel. With a diameter of 1400 mm, this high-performance milling wheel achieves the previously unattainable non-stop milling speed of up to 2 km/h. Standard HPM Reduced residual waviness due to larger milling wheel diameter Conventional The right solution for every task ENVIRONMENTALLY FRIENDLY Deeper, faster and more precise Vossloh Milling is kind to resources and the environment and regarded as the cleanest rail processing method available. In today s standard process, the rail head is re-profiled very precisely using peripheral milling in combination with peripheral grinding for the finish. Incorporating two milling units and a grinding unit coupled together, it is a procedure that functions according to the principle of mill, mill and grind fine. Vossloh milling trains can be used with most standard-gauge and private railways. Level crossings are machined along with the rest of the route and prior dismantling of signaling equipment or other systems is not required. The trains traverse the track routes at an average speed of 13 m/min. The maximum machining depth is about 2 mm on the contact surface and 5 mm on the running edge. After the milling process, the rails are checked for defects and machining quality by integrated and/or external measurement devices. The result is a dimensionally accurate restoration of the rail profile with a guaranteed transverse profile accurate to +/- 0.3 mm* and a longitudinal profile accurate to 0.02 mm. The quality of the surface roughness is Ra < 10 µm. No grinding dust No sparks, no fire hazard All the metal chips are extracted Completely suitable for use in tunnels Can also be used in sensitive areas Dry machining without water Reduced noise through optimized wheel-rail contact REFERENCES Besides the German core market, Vossloh also mills internationally in many other European railway markets (Switzerland, the Netherlands, Sweden and Denmark, among others). * but usually better than +/- 0.2 mm Corrugations, deformations and fatigue damage: In order to avoid the necessity of expensive rail replacement, Vossloh has further refined its existing milling technology: We call the result High Performance Milling (HPM). This method rectifies defects precisely and accurately re-profiles the rail, removing up to 3 mm of metal from the running surface and up to 10 mm from the running edge in a single pass! In the post-machining phase, instead of grinding Vossloh uses modern face-milling technology which produces no grinding dust, making HPM the cleanest rail machining procedure in the world. A tool calibration system ensures the work is of consistent quality, and the rails are subsequently checked by integrated measuring technology that takes longitudinal wave, transverse and, if required, eddy-current measurements. Once machined using HPM, the rail profile easily fulfils the requirements of the Deutsche Bahn Directive No. 824. Work in tunnels or inner city areas requires no extensive clean-up afterwards, and the diesel-electric drive also provides maximum energy efficiency. High Performance Milling is adaptable to all common international profiles and can be used for local and heavy-traffic routes. ADVANTAGES Our milling wheel is now twice the size Dust-free finishing technology as post-machining process Modular: 1 2 milling units and 1 finishing unit. Milling module, drive module, chip bunker module, work shop module etc. mounted on container wagons and connected according to the plug-and-play principle Higher operating speed Machined rails given the highest surface quality Exact restoration of rail profile in a single pass More material removal per operation Integrated finishing technology The rail s service life is increased Maximum fire safety thanks to spark-free operation Very environmentally friendly Reduces rail noise 12 13
Flexis Switch Maintenance Flexis: systematic care The Flexis System: optimal prevention and switch maintenance With its Flexis System, Vossloh is implementing its holistic approach to switch maintenance. As fundamental elements of a railway network, switches are exposed to high loads. Wear and tear can produce defects such as skid spots, head checks and corrugations which can result in switches having to be replaced prematurely. Periodic preventive measures considerably reduce the switch s susceptibility to breakdowns. With Flexis, the switch is checked regularly, preventively ground and any damage discovered is always repaired while still in its early stage. This ensures operational safety, keeps costs down and extends the switch s service life many times over. And what s more: the minimal rail roughness and the restored rail profile combine to reduce noise emissions. THE FLEXIS SYSTEM Machines for transverse and longitudinal profile machining Material removal exactly according to identified requirements Machining work can be documented in writing or digitally Performance example: new rail with a 300-meter radius machined in approx. 4 hours Coordinated package of measures Removing mill scale after installation is the ideal start to switch maintenance. In addition to removing defects, Flexis also has preventive switch grinding as one of its central components, ensuring that all parts of the switch that come into contact with train wheels remain in top condition. The switches are machined in several passes by our Flexis team, who use machines designed and further developed by Vossloh which can be on-railed and off-railed quickly. Track possessions as brief as 10 minutes are already sufficient. Our strategy is based on recording and documenting the condition of the switch. Vossloh uses various tools for this purpose including DQM to record the transverse profile, RM 1200 digital to determine the longitudinal profile, RHM for measuring the loss in rail height, and a WPG eddy current tester to detect the depth and spread of rail damage. The eddy current test determines the location and depth of defects while rail geometry measurements are taken in order to aid the process. THE BENEFITS OF A SYSTEM Fast on-railing and off-railing Can also be performed during short track possessions No removal of track switching equipment required Switch machined completely, including tongues and frog Eddy current testing according to DB requirements Optional adaptation of system to the scope of work required Frog re-profiling Reconditioning welding carried out if required System is DB-approved for all routes 14 15
Find out about our other rail maintenance services: Vossloh Rail Services GmbH Hannoversche Straße 10 21079 Hamburg Germany Tel. +49 40 430931-0 info.lifecyclesolutions@vossloh.com www.vossloh.com 9/16