Rubber tyres

[Parkey]

Has anyone else seen this crazy idea by the tories to fit rubber tyres to trains to "solve the capacity problem" on commuter lines into London? I can't find the article off hand, but basically the idea was that it'd allow trains to accelerate and decelerate much more rapidly, so they could run closer together.

Sounds to me like another politician deciding they want to play engineer.

[Griff]

Rubber tyres work on the Paris Metro, the trains are seperated by 1 minute 20 exactly, iirc. Of course thats metro and not heavy rail

[m3henry]

the answer is 'infrastructure, infrastucture, infrastructure.' but the government just can't accept it
I suppose money, double deck trains, more money, British Rail & even more money could help

[Ploes]

Same with the Montreal Metro (which is based on the Paris metro).

But the fact that its a completely different technology, not even just light/heavy rail. They don't even run on "rails" it looks more like floor boards than anything else.

Will be interesting to read this arttical if you do find it!

[Kevo00]

Well of course all trains have rubber tyres anyway. Little known fact about railways no. 1.

Since when were the Tories actually interested in spending money on railways anyway?

[chevyrider]

A ridiculous idea.

The secret of economic-driving is the steel on steel contact. (wheel -rail).
A train can easily drive over a distance of 30 km without traction.
I don't see a bus do that.

The profile of the wheel surface is very important .
When there is a slightly disturbance on the surface of the wheel you feel it at instant. (less then 1 mm).
It has to be smooth for a comfortable journey.

Over 1500 hp on one axle.
That can't be done with rubber tires and hold that for over one year without maintenance.

Braking will even give larger forces on the wheel.

I've been sliding once with a train containing a loc and 8 carriages.
With 130 km/h speed i stopped after some 1500 meters.
All axles had a flat spot of over 8 cm ( some 3 inch) and had the be rounded again.

With rubber tyres it should have been derailed or got fire.

[Parkey]

To be honest I don't think the tories would invest any more in the railways, and this idea just highlights how disconnected from the real world politicians are. Depressing really.

Fitting rubber wheels on trains is ridiculous when we have a national system designed for standard gauge trains with many routes overlapping and using the same track. Not running steel wheels on steel rails also makes rail's environmental advantages vanish instantly.

If they really want to speed up acceleration and deceleration perhaps fitting linear electric motors between the tracks to give the trains an extra boost out of stations and assist with the braking on the way in would be an idea, but to be honest the acceleration of a modern EMU is pretty good anyway.

[XeryusTC]

A train can easily drive over a distance of 30 km without traction.
I don't see a bus do that.

A train weighs a bit more than the average bus and thus posseses more kinetic energy while driving at the same speed which ultimately gets it further when both wheel types have the same amount of friction (assuming that both vehicles also have the same air resistance).

I agree that rubber tires are silly for trains though, you'll need very strong rubber to support the weight of the train, or you'll need more wheels so the weight gets distributed better and the wheels don't blow because of the sheer pressure. It will probably also be a royal maintenance PITA, steel sounds way better to maintain . And think of trains getting a flat tire, I bet that the train would derail when it gets a flat tire.

[Parkey]

It's not about mass really, it's more about the coefficient of rolling friction. It will vary, but on average for train it's about an order of magnitude (x10) less than for a vehicle like a bus with rubber tyres. That's one of the reasons why trains are more energy efficient than road vehicles.