Trams and the cycle of sand

When travelling on a Melbourne tram, you might have noticed a little window of sand next to your seat. So what’s the story?

Steel wheels rolling on steel rails might be a low friction surface for moving along efficiently, but when it is time to stop, a tram needs all of the friction it can get – and dropping sand onto the track is the easiest way to achieve it.

The story of sand on trams starts at the depot, where trucks deliver clean sand into a tall tower.

Semi trailer refilling the sand tower at Essendon Depot

Hoppers onboard each tram carry the sand, which are refilled when required.

B2.2072 stabled in road 12 at Essendon Depot

The little windows allow the amount of sand inside each hopper to be checked.

Sand box indicator in the saloon of a D2 class tram

Inside the driver’s cab, there is a button to drop sand.

Drivers console of E.6001

When pushed, the pipes from the hoppers open, dropping sand onto the tracks just in front of the wheels.

Sand on the tracks where Z3.205 put on the brakes

As well as giving extra friction between the tram wheels and the rails, sand also serves as an electrical insulator – an unwanted attribute that results in electrical arcing when too much builds up on the tracks.

Arcing between the wheels and rails of a Z3 class tram on William Street

The sand also ends up in the flangways of the rails, making a mess.

Sand and fallen leaves cover the tram tracks in William Street

To prevent this, Yarra Trams has a fleet of modified street sweepers to vacuum the sand back up again.

Yarra Trams street sweeper vacuuming sand out of the flangeways

Unlike a normal street sweeper, the tram track cleaner has a special attachment to get the last bits of sand of the rail flanges.

Close up of the cleaning head of the hi-rail tram track cleaner

Unfortunately the circle of sand isn’t a complete one, as the recovered grit can’t be reused in trams – specially filtered and dried sand is required, or the hoppers and pipes get clogged up.

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7 Responses to “Trams and the cycle of sand”

  1. Great post Marcus! I’ve always wondered about this.

  2. David says:

    I wonder if YT have investigated using the same conductive sand-compound as the Metro Siemens fleet?

    • Dark Knight says:

      “Conductive sand-compound” I must say that’s one fancy way to put it.
      I can’t speak for YT or any other locomotive servicing companies which operate in Victoria.

      But the sand which MTM uses for the Siemens fleet is just ordinary fine, washed Silica Sand commonly used as Foundary Sand, Grout and in this case adhesive purposes.

      Comes from a company called Rocla, mined and processed locally at the Langwarrin plant, according to the MSDS the contents is >98% crystalline silica (quartz) and <2% mineral and organic impurities, nothing magical really.

  3. Rohan Storey says:

    Apparently that sand as grit is a great contributor to dust in the inner city, and blackening of buildings, though not entirely convinced now that I think about it.

    And I believe that the newer trams, that is all the light rail extra long ones from that last 10 years at least dont use sand, but electro-magnetic brakes. I think.

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