Trivia - Working of trains on inclines

[The Planner]

Am I right that the Liverpool to Drax biomass trains are still banned from Miles Platting heading east (ie loaded)?

There have been several recent trials looking to see what can realistically be pulled up there, it hasn't led to anything yet though.

 

[Millisle]

Strangely, back in the day a Class 40, normal power in the 1960s-mid 70s on full-size Aberdeen-Edinburgh services, even the heavy overnights to Kings Cross, and at 2,000hp less than a single HST power car, regularly called at Inverkeithing (principally for the Navy traffic from Rosyth) without issue.

The issue, I think, was not power but adhesion. Slipping was a commonplace over the years that I used the Highland Chieftain, with shuddering jolts down the train as one or other power car lost its feet.

 

[AM9]

Strangely, back in the day a Class 40, normal power in the 1960s-mid 70s on full-size Aberdeen-Edinburgh services, even the heavy overnights to Kings Cross, and at 2,000hp less than a single HST power car, regularly called at Inverkeithing (principally for the Navy traffic from Rosyth) without issue.

As Millisle says, it's not about power, that's needed on the 43s to get to 100+ on flat or relatively mild gradients. Adhesion is important, and even more important is tractive effort; the 43s have around 17000 lb TE, as opposed to the 40's 52,000 lb starting and 30,000 lb at low speeds, - about twice that of the 43s.

 

[Ken H]

As Millisle says, it's not about power, that's needed on the 43s to get to 100+ on flat or relatively mild gradients. Adhesion is important, and even more important is tractive effort; the 43s have around 17000 lb TE, as opposed to the 40's 52,000 lb starting and 30,000 lb at low speeds, - about twice that of the 43s.

and wheelslip pretection. I remember in the 1980's the breakthrough using doppler radar. before then the driver did what he could. Braking too. When Wheel slide protection came in on MU's, the drivers hated it because the wheels under the driver were cycling between braking and letting go as they tried to get a grip, while brakes towards the back were doing OK on the rails that had been cleaned by the front wheels.

 

[AM9]

and wheelslip pretection. I remember in the 1980's the breakthrough using doppler radar. before then the driver did what he could. Braking too. When Wheel slide protection came in on MU's, the drivers hated it because the wheels under the driver were cycling between braking and letting go as they tried to get a grip, while brakes towards the back were doing OK on the rails that had been cleaned by the front wheels.

But the alternative would be for the drivers to get a smoother ride, - until those wheels slipped so much that they had flat tyres.

 

[Ken H]

But the alternative would be for the drivers to get a smoother ride, - until those wheels slipped so much that they had flat tyres.

With tread brakes, the brakes clean the wheels. The downside of disk brakes is the brakes didnt keep the wheels clean. And better bogies meant there was less hunting, which also cleaned the wheels. But disk brakes + decent WSP was deffo a move forward.

 

[sw1ller]

It's not uncommon for 6J37 to be held just after Pulford LC if a passenger train is heading from Wrexham at the same time. With a 70 pulling it, it'll still be going above 30mph over the top of Gresford Bank with a run or from a stand, with 66s (or when Colas had them, 60s) it would be mid-20s mph, even from a standing start at Pulford. It's only 1400 tonnes. Only time you'd drop to 12mph would be during leaffall, and even then it'd be rare, say if drizzle was falling, although it has slipped to a stand and required assistance on a small number of occasions - I was banked up when it happened to me during my handling hours training in 2014.

== Doublepost prevention - post automatically merged: 13 Aug 2021 ==


It's most definitely not, or I'd want words with someone, having been stopped with a 1700 tonne train at Horton and again at Ribblehead one day last week...

Ahh, well there ya go then. The driver I was speaking to was route refreshing in with me and had only been driving them a short time. I had no reason to disbelieve him though. Maybe he meant in leaf fall then.

 

[AM9]

With tread brakes, the brakes clean the wheels. The downside of disk brakes is the brakes didnt keep the wheels clean. And better bogies meant there was less hunting, which also cleaned the wheels. But disk brakes + decent WSP was deffo a move forward.

I wasn't advocating that as a solution, merely a response to the drivers complaining about the contemporary WSP.

 

[ValentaFan1974]

IIRC they could run in the down direction unassisted due to failure as long as they had a clear run through the DM at Totnes.

That’s right. If an XC HST has a dead power car, it’ll skip Totnes and pass through at full whack (up to line speed of course) in order to climb the bank.