WonrosTM technology in rail technics

By Dr. Andrej Godec, Director of Slovene Agency for the Management of Public Railway Infrastructure Investments

WonrosTM (wear out and noise reduction on source) technology deals with use of the so called HFC (heavily fluid composite) compounds and applicators, i.e. devices for distribution of HFC materials, intended for reduction of wear and tear and noise production for devices and machinery operating under extreme conditions, particularly on rails, in the field of rolling noise and wear and tear.

A lot has been written on the subject of noise production and wear and tear of rails. Consequently, the intention of this article is to clarify certain doubts regarding lubrication and, particularly, to present the problems and their relevant solutions in a simple, comprehensible, and useful manner. Years of experience of working on railways and professional literature from the field of wear and tear and noise production of rails and wheels of railway vehicles have been taken into account. The recommendations of the European Commission to primarily consider solutions which resolve the problem on source have also been adhered to. Interesting and successful solutions and potential useful options of applications supported by WONROS™ technology are presented.

Even the worst rolling noise on rails may be controlled. With the use of patented solutions for rail systems, supported by WONROS™ technology:

- rail/wheel generated noise,
- wear out of rails and wheel flanges,
- GCC – gauge corner cracking,
- RCF – rolling contact fatigue,
- sinus line (corrugation),
- LCC – life cycle costs, etc. can be decreased, and
 
RAMS:
 - reliability,
 - availability,
 - maintainability,
 - safety can be increased.

Advanced WONROS™ technology facilitates successful reduction of noise and wear and tear at the source itself
The two phenomena occur because of friction between metal surfaces, which are subjected to continuous changes; both, in terms of strength and in terms of the source point (micro-location). This dynamic, particularly on rails, is caused by an infinite amount of variables, such as different weight of axis, different wear and tear of profiles, also damaged contact-running parts of wheels-rails, variable speeds, changes of temperatures, humidity, etc. This technology involves the development and use of special media, the so called HFC (Heavily Fluid Composite) compounds – materials which preserve the surfaces exposed to torsion, for example, wheels, rails, rail brakes etc., against wear and tear and noise production. Because of the requirement for automatic application or dosage, special dosage devices have been developed, which are capable of applying very complex HFC materials for distribution completely automatically.

The entire technology is thus based on patented multi active rail preserving systems; special heavy duty devices, which were designed for rail maintenance and which are simultaneously energy independent and unattractive for vandals, apply special long lasting, temperature resistant and environmentally friendly composite materials at the source of noise – at the right time, at the right place and in the right amount – reliably!

Maintenance of rails and the importance of wayside applicators (Track-Side-Systems)
Based on the fact that lubrication and grinding are the most important measures of economically efficient maintenance of rails, and indirectly wheels, we may conclude that grinding is defined as the re-profiling of the track railhead, while the cycle between grinding may be extended by efficient lubrication of wheels and rails. The preferred philosophy of WONROS™ technology does not reference standard lubrication but, rather, the application of a microfilm of a special HFC medium-material (HFC – Heavily Fluid Composite). This is a type of fluid compound mixture, capable of withstanding extremely great pressure, exceeding 8 t/cm², while not fundamentally modifying the adhesion between the wheel and rail, i.e. traction. In practice, these materials dramatically decrease wear and tear, and almost eliminate noise generated between the wheel and the rail, i.e. the coarse, grinding noise. This noise represents the high wear grinding of the gauge corner as also, to the human ear, an extremely disruptive high frequency squeaking generated by the exterior edge of the railhead (clearly demonstrated by films from nature at www.wonros.eu). An important quality of these materials is also the relatively high content of aluminium, which prevents the formation and spreading of micro-porous cracks and reduces rail sinus-line corrugation.

Since the basic intention of the article is to particularly present the new generation of stationary devices for provision of track lubrication, it shall be primarily emphasised that the belief that lubrication devices on-board locomotives eliminate the need for wayside applicators is wrong. Even the most efficient on-board locomotive lubricators are not able to maintain the gauge corners of exposed rails and in sharp curves. Specifically the on-board applicators available at present cannot affect the squeaking-squealing generated between the wheel and the rail since the application is limited to the radius of the wheel. On-board applicators are thus limited particularly to the maintenance of the interior edge of locomotive wheels (QR) and to a lesser extent contribute to the maintenance of rails.

Quality wayside applicators, which are capable of distributing HFC materials through the openings of the railhead*, in continuation stated as HFC applicators, facilitate, particularly due to the above, very precise application to the points on the railhead where the high frequency noise is generated due friction, thus dampening the noise, i.e. reducing the power of noise up to 100%. This noise is not extremely disruptive only for the environment; it also contributes to cracking of the rail and, through oscillation and resonance, accelerates spreading of cracks, which can result in brakeage of the rail, and is consequently a very important factor of traffic safety.

*Company ELPA has patented and certified (TÜV Süd Rail) the application openings on the railhead; these facilitate expansion of material to the specifically defined points of railhead, which in turn facilitates selective treatment of individual desired effects, either noise reduction, wayside wear and tear or the wear and tear of the top of railhead. With this method the required dosage could be significantly reduced and thus the utilisation rate of used material could be extremely increased (÷ 99.8%).

Important advantages of application through openings include:
a. A great advantage of these applicators is the fact that they can be placed in the centre of the curve, which is particularly useful on a two-directional track. Wheels distribute the material in both directions and one device replaces two classic devices, fitted on the straight section prior to the curve.
b. The advantage of application through the openings in terms of safety is also the fact that the edge of the track is not fitted with application knives, which, with ever increasing operational speeds of vehicles, damage the wheels, i.e. wheel flanges.
c. The passage of a maintenance vehicle requires only the removal of the sensor and even that only in case the sensor is not fitted in the railhead.

Economic and environmental effects of lubrication with the use of WONROS™ technology*
If we generalise the positive effects related to reduced usage of traction energy, i.e. reduction of noise, reduction of costs resulting from less frequent maintenance and, indirectly, due to less changes of regimes of execution of regular traffic, etc., and orient ourselves only on the reduction of grindings introduced into the environment and the expansion of the cycle between grinding, it follows:

On one curve equipped with quality lubrication, approximately 11,000 EURO may be saved per year and the emission of steel grindings into the environment reduced by ≈1,500kg or, for the same quantity, the use of natural raw material sources may be decreased. In addition to the above, quality lubrication facilitates soft passage of vehicles through curves. In this manner we decrease the vibrations, which damage the gravel bed and decrease the possibility of derailment and, thus, facilitate comfortable and safe transport of passengers.

If the HFC applicators are fitted on a number of points along the curve, the required dosage of each is decreased and the utilisation rate of material is almost 100%. In this case, the service life of rails and wheels is considerably longer and the rail environment is maintained very clean.

With the use of HFC applicators we increase Reliability, Availability, Maintainability, Safety (RAMS) and decrease of Life Cycle Costs (LCC).

From an economic standpoint, each correctly applied Euro of lubricant per rail equals a saving of at least 2,5€ in maintenance and considerable potential ecological benefits via which infrastructure systems, the size of railways, can influence the global ecology trends. *Note: For upper comparison CL-E1ws application was used.

With HFC applicators also  the braking noise caused selectively by cast iron brake blocks on wagons can be reduced
With HFC applicators we may also reduce the braking noise caused selectively by cast iron brake blocks on wagons, for example, prior to arriving at stations, stop signs, passing schools, hospitals, etc. The comparative advantage of such an application is in the fact that reduction is executed based on the hierarchy of the problem and the investment capabilities, while the effects are heard immediately following the activation of the system. Alternatively, the brake systems of all wagons must be replaced to achieve the desired effect, since, as we know, noise is compounded logarithmically. In practice this indicates that the noise produced by a 20 wagon train-set (of which 15 are equipped with »noiseless« skids while 5 are equipped with noise producing cast iron brake blocks) and introduced into the environment shall not fundamentally change.

As mentioned, HFC materials can withstand extremely high pressure and this is precisely why the use of HFC applicators is sensible also for maintenance of switches, particularly switch blades as the most exposed transit points.

So called HFC underground applicators also exist, for example CL-E1ug, which are intended particularly for maintenance of rails where no external foreign bodies are permitted, or there is a danger of damage of the device due to vandalism. The device is manufactured as waterproof and is simply lowered into a standard concrete shaft at fitting.

Summary
In all cases of application of CL-E1 devices, the WONROS technology has proven in practice to resolve the until recently irresolvable problem of many railway infrastructures: in terms of noise production in the urban environment particularly in avoiding possible actions for damages of the surrounding inhabitants, while providing passenger comfort and long-term relatively high savings in terms of maintenance. The fact that the implementation of devices, supported by WONROS technology, has clearly confirmed certain theories-explanations, particularly relating to the requirements of lubrication with stationary lubricant devices, is also significant. Stationary devices are necessary, particularly if they are of such quality to be able to solve a number of problems simultaneously (noise, wear and tear, cracking of tracks, sinus-line corrugation), without excessively polluting the rail environment and operating reliably with minimal maintenance expense.

References:
1) Diamond, S. and Wolf, E. (2002) Transportation for the 21st century, TrackGlide Top-of-Rail Lubrication System, Report from Department of Energy, USA
2) EIM position paper rail/flange lubrication (2008) EIM (European Rail Infrastructure Managers). Available Online: http://www.eimrail.org/documents/EIMPPFlangeLubrication_000.pdf. Access date:  09.06.2009
3) Hemsworth B. (2008) Environmental Noise Directive Development of Action Plans for Railways, UIC (International Union of Railways)
4) IEC 62278 (2002) Railway applications – Specification and demonstration of reliability, availability, maintainability and safety (RAMS), Commission Electrotechnique  Internationale, Geneva
5) Kostiov L. (2009, 02-03) Razvoj naprave CL-E1 za mazanje tirnic, Nova proga, Revija Slovenskih Železnic
6) Prasad A.P. (2007) RAMS and LCC in Rail Track Maintenance, Luleå University of Technology, Division of Operation and Maintenance Engineering, Lulea, Sweden. Available Online: http://epubl.luth.se/1402-1757/2007/57/LTU-LIC-0757-SE.pdf. Access date:  09.06.2009
7) Vitez I., Oruč M., Krumes D.,  Kladarić I.(2007) Damage to railway rails caused by exploitation,  Metalurgija 46. Available Online: http://public.carnet.hr/metalurg/Metalurgija/2007_vol_46/No_2/MET_46_2_123_128_Vite.pdf. Access date: 09.06.2009
8) WONROS™ technology, Wear Out and Noise Reduction On Source. Available Online:
http://www.wonros.eu. Access date: 09.06.2009