Rail wear has been a challenge for many years in areas of tight curves or heavily loaded tracks. Not only is wear a problem in dry weather, the so-called curve screeching or squeal can be a problem in built up or residential areas.

One cause of this is simply wheel flange rubbing against the side of the outer rail. Another cause is the “stick-slip” effect, this is when the train is turning, the inside wheel has a shorter distance to travel than the outside wheel, because of the solid axle between the two the inside wheel slides to compensate the difference.

To reduce this wear and noise, lubrication is required, and we can provide a system to lubricate the rail automatically, reliably where it’s needed.

Train and Tram Lubrication Solutions

Wiper Bar

To reduce the friction between the wheel flange the Graco wiper bar will apply lubrication to the wheel flange where it will stay for several kilometres, eventually building up a layer of lubrication on the track for protection.

The wiper has 12 outlets, the grease line to the wiper is divided in 12 by use of a progressive metering device. This device uses injectors to ensure each outlet gets the same amount of grease. It is also greatly increases the reliability ensuring no outlet gets blocked and allows operation into minus temperatures.

Top of Rail Applicator

The SLID top-of-rail applicators operate on the single-line concept in which 4 nozzle chambers are filled with a predetermined quantity (4 x 0.1 cm³) of friction modifier. Simultaneously, a spring and piston mechanism is charged, and when the pressure is vented from the mainline, it discharges and applies the friction modifier to the top of the rail. This enables the controlled delivery of friction modifier.

The wheels spread the friction modifier over several hundred meters of track which dampens the hard slipping of the wheels – also called stick-slip-effect. Curve squealing or screeching is therefore prevented.

As the characteristics of metal pastes (so called friction modifiers) change at low temperatures, the applicators can be equipped with internal heaters. The applicator heater keeps the temperature of the friction modifier within the metering chamber constant in order to enable a steady, even and reliable squirt pattern.

Metro and Tram Rails

In comparison to mainline trains, the tracks of trams are not as highly loaded, which is why lubricant channels that are drilled into the rails can be used. The lubricants or friction modifiers are brought to the lubrication point via high pressure hoses.

Controller Systems

The rest of the lubrication system can be securely stored away in a cabinet on the side of the track. This unit would contain, the pump, lubricant reservoir (5 litres upwards), the controller, and optional remote monitoring and solar power units.

The controller system is also extremely flexible in its placement. It can be placed at a distance from the track if required, one pump can feed several greasing systems, and even supply several systems at either end of a large bend. By use of progressive metering a single line can be run and divided where required. Graco’s SSV dividers always ensure a reliable lubrication.