Running a steam loco on a 1/30 grade - does it have to be chimney first?

[PhilH]

14 minutes ago, LMS2968 said:

Not necessarily. If you are in charge of a poor steaming engine struggling with a heavy train against a gradient, and you're watching the pressure gauge dropping back, and the level in the gauge glass is falling, what do you do? If you put the feed on, you are putting (comparatively) cold water into the boiler, and its immediate effect is the cause the pressure to drop further. So you use the feed sparingly, allowing the water level to fall in order to maintain enough steam pressure to get you to the summit. This process is known as 'mortgaging the boiler', and once over the top the driver can ease up and the pressure can rise. And there's the danger.

 

As the summit is passed and the engine starts downhill, the water, already not too high in the glass, disappears down to the smokebox end. What's more, when the driver had the regulator open, the flow through the valve lifted the water level; if he now closes it this means a further fall in the level. The Horwich Crabs had a bad reputation for that. So the fireman, who had managed to keep half a glass during the climb watches the water disappear below the bottom nut as they go over the top.

 

It isn't as easy as just saying, 'Keep enough water in the glass.'

I do get that, and have experienced that scenario on the footplate of 34046 on Sapperton Bank through black stuff that, well, I don’t think it was coal, and the same scenario on Hosking’s A4’s last run into King’s Cross.., and I get that it was perhaps different back in the day when if things did go belly up you could just whistle up another engine. We had to stop for a blow up which caused chaos but to me that was part of the boiler management, ie not causing a worse problem by just carrying on and perhaps dropping said plug.

 

I suppose what I am really trying to say is you don’t run on a wing and a prayer as far as water level is concerned, just hoping that it will be alright…you have to do something about it. And that is what I call boiler management.

 

Edited January 18, 2023 by PhilH

[LMS2968]

There's a big difference between preserved main line steam and the real world.

 

Back in the day, that's what you had to do.

[asmay2002]

As far as I know they didn't turn locos just to go down the 1 in 37 Lickey Incline tender first in steam days...

Edited January 18, 2023 by asmay2002

[Jeremy Cumberland]

4 hours ago, rogerzilla said:

Indeed, and if the water was already near the bottom of the glass, the fusible plug could give up.  Putting the injectors on and closing the dampers might not be the first thought if a signal is suddenly thrown to "danger" in front of the train or there is an obstruction spotted up ahead.

Putting the feed on will very likely be one of the first thoughts of the fireman if the driver closes the regulator, although they probably won't be thinking of the fusible plug. Firemen have to be ready to respond to drivers' actions

 

3 hours ago, LMS2968 said:

A dropped plug isn't an instantaneous reaction to a water surge, but they can be cumulative. A driver might allow to be uncovered for only a few seconds to have it fail, as it has already been uncovered many time in the past. This is why plugs are consumables and regularly replaced, not just when one gives up the ghost.

I've come to prep an engine and found a partially-melted fusible plug. I happened to have been fireman the previous day, so knew exactly what had happened. We had absolutely rubbish fuel, which also contrived to progressively block the tubes as the day wore on (I've no idea what was in it; something light and incombustable at any rate). Steaming, as might be expected, was attrocious.

 

My driver was game and knew exactly what the situation was, as I struggled to keep steam and water, having a blow-up whenever we stopped in a station, but we managed to keep going between stations. On the second trip (of two), as we approached the summit I had already let the pressure drop as low as I was happy with (from memory, about 120 psi from a working pressure of 180), and the driver made no suggestion that I should let it drop further to get some water in. The water was at the bottom of the glass (nothing unusual when things weren't going well), and I thought we'd stop for a blow up before going over the top. We didn't stop. The moment the driver closed the regulator I had the feed on full (and the blower open full - I needed to keep the fire going; it was hardly roaring away, after all), but I am not sure that I saw the water again till we started going uphill about half a mile later. At least we now had enough water to get to the end of the line.

 

[Poor Old Bruce]

In South Africa, on the 1 in 36 Montague Pass working from George, I believe the crews preferred the Garratts to be chimney trailing to keep any smoke out of the cab.

[LMS2968]

There are many instances of engines being worked up gradients which might be considered the wrong way around. The climb out of Bolton towards Darwin and Blackburn was a bank engine section, and this was usually a Lanky 'A' class with a very low tender. It therefore banked trains uphill tender first, the train ahead providing some protection from the weather. The return to Bolton was therefore chimney first with weather protection provided by the spectacle plate.

 

Chimney first was desirable, but other factors sometime overrode this.

[TheSignalEngineer]

14 hours ago, asmay2002 said:

As far as I know they didn't turn locos just to go down the 1 in 37 Lickey Incline tender first in steam days...

They would have been the wrong way round for the climbs from Saltley.

 

[bécasse]

14 hours ago, asmay2002 said:

As far as I know they didn't turn locos just to go down the 1 in 37 Lickey Incline tender first in steam days...

One of my father's sisters lived close to the Lickey Incline and when we visited her in the early sixties one of my cousins took me to see the top of the incline. A 4F 0-6-0 was just restarting a southbound goods train from its stop to pin down wagon brakes when we got there. The sight and sound of the effort it had to put in to get that train moving and keep it moving until the whole train was on the incline was such that it remains with me to this day; the loco was certainly chimney (and a very impressive column of smoke) first.

[LMS2968]

Sounds like someone was a bit too keen pinning down the wagon brakes. The ideal situation is that the engine draws the train forward slowly and the shunter pins down each wagon brake as it passes him, and the driver can feel the retardation and call a halt when he assess that enough brakes are down. This should allow the train, with the brake van screwed down, to roll at a constant speed down the gradient, possibly with the tender handbrake also screwed down and the engine steam brake in reserve. It wasn't and easy judgement and they didn't always get it right.

[mcowgill]

On 17/01/2023 at 21:13, Butler Henderson said:

According to Festpedia https://www.festipedia.org.uk/wiki/Turntables the Boston Lodge one was in use intil at least 1934 and is stated as now being underneath a garage. It would be useful to allow the single locos to face uphill when they work on the WHR to Beddgelert

No real need for it, the England engines have regularly been turned for events & photo charters.  Separate the loco from it's tender and they can both be turned on the wagon turntables at Boston Lodge.  

[The Stationmaster]

17 hours ago, LMS2968 said:

Not necessarily. If you are in charge of a poor steaming engine struggling with a heavy train against a gradient, and you're watching the pressure gauge dropping back, and the level in the gauge glass is falling, what do you do? If you put the feed on, you are putting (comparatively) cold water into the boiler, and its immediate effect is the cause the pressure to drop further. So you use the feed sparingly, allowing the water level to fall in order to maintain enough steam pressure to get you to the summit. This process is known as 'mortgaging the boiler', and once over the top the driver can ease up and the pressure can rise. And there's the danger.

 

As the summit is passed and the engine starts downhill, the water, already not too high in the glass, disappears down to the smokebox end. What's more, when the driver had the regulator open, the flow through the valve lifted the water level; if he now closes it this means a further fall in the level. The Horwich Crabs had a bad reputation for that. So the fireman, who had managed to keep half a glass during the climb watches the water disappear below the bottom nut as they go over the top.

 

It isn't as easy as just saying, 'Keep enough water in the glass.'

And of course putting on an injector doesn't just add cold water to the boiler but it also uses some of that steam you are already short of.

[kevinlms]

15 hours ago, asmay2002 said:

As far as I know they didn't turn locos just to go down the 1 in 37 Lickey Incline tender first in steam days...

There are also places where there are steep grades in both directions (not necessarily the UK). Locos didn't get to the top chimney first, visit a turntable or reversing wye, then go tender first down the other side!

[Rivercider]

I have just been reading about the St Blazey to Fowey china clay traffic in the steam era. From St Blazey the line climbs at 1 in 36 up through single track Pinnock Tunnel which at 1,173 yards long is the longest in Cornwall. From the tunnel there is a steep descent to Fowey. The GWR 2-8-0T or 2-8-2T tanks used on the line were run bunker first with loaded clay from St Blazey to make things more bearable for the crew going up through the tunnel.

 

cheers

Edited January 19, 2023 by Rivercider
tidying up.

[The Stationmaster]

1 hour ago, LMS2968 said:

Sounds like someone was a bit too keen pinning down the wagon brakes. The ideal situation is that the engine draws the train forward slowly and the shunter pins down each wagon brake as it passes him, and the driver can feel the retardation and call a halt when he assess that enough brakes are down. This should allow the train, with the brake van screwed down, to roll at a constant speed down the gradient, possibly with the tender handbrake also screwed down and the engine steam brake in reserve. It wasn't and easy judgement and they didn't always get it right.

No - they were doing it properly on the Lickey as explained above.  You should have enough brakes pinned down to hold the train stationary with no brakes applied on the engine or the brakevan.  The engine then has to work against the wagon brakes to get the train moving.  The theory - and hopefully the practice - is that you then rely on the wagon brakes to keep the speed down to the right level leaving the engine and brakevan brakes in reserve should you need them.  The only problem with the theory is that on a long, steep, gradient you can end up with wagon brake blocks getting so hot and worn that their braking power reduces - but the same, or worse, would happen to the loco brakes if you started to rely on them instead or, as well as, the wagon brakes. 

 

Now I fully accept the difference between theory and reality when it comes to incline working and I know from direct experience that depending on train weight and the nature of the gradient it is still possible for speed to build up even with the wagon handbrakes holding the train when you started off.  But it s not safe practice to run down a gradient without applying sufficient wagon handbrakes at the top to hold the train stationary on the gradient and i have seen a graphic illustration of what can happen when somebody ignores that procedure.  The other problem is that if you rely too much on the engine brake you will lose braking effect and that too can result in a runaway and I know of one place where despite speed getting well above what it should be with a diesel hauled train it was folly to try to reduce speed using the lovco brake because there was more than enough gradient to destroy even a new set of brake blocks.

[LMS2968]

The Lickey certainly had its own rules for gradient working not found anywhere else, such as three or four bank engines coming on the back separately, never coupled together, all carrying a head and tail lamp, and all dropping off independently at the summit. I'd be surprised if they pinned the brakes down with the train stationary though: if enough were pinned down to hold a constant speed on a 1:37.7 gradient, it's going to be a lot of fun getting them rolling again on a fairly level stretch at the top.

[rogerzilla]

55 minutes ago, The Stationmaster said:

And of course putting on an injector doesn't just add cold water to the boiler but it also uses some of that steam you are already short of.

You do,however, get back most of the thermal energy as the condensing steam heats the incoming water from cold, so it's more efficient than a feed pump would be.  A feed pump would extract about 15% of the energy in the steam, like any reciprocating engine using railway pressures, and waste the rest.  M. Giffard was a clever bloke.

[KingEdwardII]

On 17/01/2023 at 18:31, Jeremy C said:

Glanpywll

Small correction - it's Glanypwll.

Sorry, but the mistake grated with me. In Welsh, "pwll" == pool or pond, "glanypwll" == "shore of the pool".

[MarkC]

2 hours ago, kevinlms said:

There are also places where there are steep grades in both directions (not necessarily the UK). Locos didn't get to the top chimney first, visit a turntable or reversing wye, then go tender first down the other side!

Scarborough to Whitby line - 1 in 39 and 1 in 43 climbs either side of a very short (almost) level section at the summit, Ravenscar.

 

It was usual for assisting locomotives on heavier trains to run chimney first, but there are photos of occasions where the pilot engine, a tank loco, has been bunker first.

[Jeremy Cumberland]

3 hours ago, KingEdwardII said:

Small correction - it's Glanypwll.

Sorry, but the mistake grated with me. In Welsh, "pwll" == pool or pond, "glanypwll" == "shore of the pool".

I'm so sorry. I know very well how to spell the place, but when I originally typed it I accidentally omitted the letter "p". I noticed this when I saw Butler Henderson's quote a little while later, so I corrected the misspelling. Or not, as you point out.

 

It's corrected now.

[The Lurker]

3 hours ago, KingEdwardII said:

Small correction - it's Glanypwll.

Sorry, but the mistake grated with me. In Welsh, "pwll" == pool or pond, "glanypwll" == "shore of the pool".

Interestingly, it appears to be a borrowing from old English or even Latin, rather than derived from an older Indo-European common origin - sorry for the OT diversion 

[Butler Henderson]

6 hours ago, mcowgill said:

No real need for it, the England engines have regularly been turned for events & photo charters.  Separate the loco from it's tender and they can both be turned on the wagon turntables at Boston Lodge.  

But not Linda, Blanche, Talesin and Lyd presumably (nor Mountaineer should it work again)

[APOLLO]

4 hours ago, MarkC said:

Scarborough to Whitby line - 1 in 39 and 1 in 43 climbs either side of a very short (almost) level section at the summit, Ravenscar.

 

It was usual for assisting locomotives on heavier trains to run chimney first, but there are photos of occasions where the pilot engine, a tank loco, has been bunker first.

 

Like here, pulling to Ravenscar.

 

 

Brit15

[bécasse]

8 hours ago, LMS2968 said:

 ........ if enough were pinned down to hold a constant speed on a 1:37.7 gradient, it's going to be a lot of fun getting them rolling again on a fairly level stretch at the top.

Which is exactly why I remember, over six decades later, watching that very "fun". It was the most impressive performance by a steam loco that I have seen ......... by quite some way, and I have no reason to believe that it wasn't the normal practice. Clearly the cousin who took me to that particular spot knew that it was the best viewpoint, trains ascending the grade were tame in comparison.

Edited January 19, 2023 by bécasse

[The Stationmaster]

21 hours ago, bécasse said:

Which is exactly why I remember, over six decades later, watching that very "fun". It was the most impressive performance by a steam loco that I have seen ......... by quite some way, and I have no reason to believe that it wasn't the normal practice. Clearly the cousin who took me to that particular spot knew that it was the best viewpoint, trains ascending the grade were tame in comparison.

The only logical way you can get enough brake force to control the train descending a bank is by pinning down brakes actually on the gradient.  If you pin them all down on the level before reaching the gradient you don't really know exactly how many need to be pinned down.  so in many places the train was brought to a stand as it went onto the incliine to start piniinng down brakes and this continued as it ran onto the incline.  Depenfding on the wagons, their loads, and the condition of the brake blocks it won't be the same number of wagons ever time.  In many places in South Wales the only place for doing most of the pinning down was with the train on the incline. 

[LMS2968]

21 minutes ago, The Stationmaster said:

The only logical way you can get enough brake force to control the train descending a bank is by pinning down brakes actually on the gradient.  If you pin them all down on the level before reaching the gradient you don't really know exactly how many need to be pinned down.  so in many places the train was brought to a stand as it went onto the incliine to start piniinng down brakes and this continued as it ran onto the incline.  Depenfding on the wagons, their loads, and the condition of the brake blocks it won't be the same number of wagons ever time.  In many places in South Wales the only place for doing most of the pinning down was with the train on the incline. 

Which is basically what I was trying to say yesterday at 11.15!