Very early locomotive boiler feeds

Advert

New Replies

Report Bug

Help/FAQs

Very early locomotive boiler feeds

This topic has 19 replies, 8 voices, and was last updated 4 August 2018 at 03:00 by John Olsen.

Viewing 20 posts - 1 through 20 (of 20 total)

Author

Posts
9 April 2010 at 16:42 #50553
Jonathan Howes
Participant
@jonathanhowes93303
Hi all,

I have been researching the Stephenson locomotive “Lancashire Witch” for development as a 7 1/4″ gauge model for about a year now but have come up against a detail problem regarding the boiler feed pump.

This, as on many locomotives from around 1830, is driven by a crosshead coupling and the delivery is via a ram pump, so far so good.

On these early engines however the pump itself consists of typically two vertical barrels linked together with the boiler linking to the top of the uppermost barrel. Two cocks are provided, one on each barrel and I have been completely unable to find out exactly what goes on within.

Ball valves came a bit later than Lancashire Witch so the lack of space for a ball in the vicinity of each cock is not a problem, almost certainly some form of lifting plug valve is performing the same function. The problem is that any control of boiler feed seems to be almost impossible without a severe danger of hydraulic lock.

I have found three depictions of the same form of feed pump, two from drawings and one in the flesh, on “Invicta” in the Canterbury Museum but no indication of the appropriate innards. The NRM did not seem able or willing to help (although I think Invicta may have been disassembled in part for restoration) and the only other place that seems to understand really early locomotives, the Beamish museum, also presented a deafening silence.

I can post some files of the evidence to date but someone may know the answer, please wade in.

Many thanks,

Jonathan Howes.
Advert

9 April 2010 at 16:42 #944
Jonathan Howes
Participant
@jonathanhowes93303
Solving the puzzle
9 April 2010 at 19:21 #50557
KWIL
Participant
@kwil
Jonathan,

See PM

KWIL
9 April 2010 at 21:18 #50566
Chris
Participant
@chris16039
I found the curator of the manchester museum of science and industry very helpful with my enquiries about Northumbrian. They cover the Liverpool Manchester Railway history.

He is at n.forder@mosi.org.uk

Hope this helps. I too am fascinated by the very early locos and would like to know more about your Lancashire Witch. My next project will be a 5 inch oldie (there are very few about) but a 7 sounds even more exciting.

Chris.
10 April 2010 at 13:48 #50602
Jonathan Howes
Participant
@jonathanhowes93303
Does anyone have some tips on how to add images? I would like to post two different versions of the Lancashire Witch feed pump and photographs of the unit on Invicta.

Edited By Jonathan Howes on 10/04/2010 13:50:00
10 April 2010 at 13:59 #50604
Weary
Participant
@weary
This thread called Posting Photos might help.

Looking forward to seeing the pics, as I am interested in early locomotives too (though more the next ‘generation’)

Phil
10 April 2010 at 14:20 #50605
Jonathan Howes
Participant
@jonathanhowes93303
One from the Stephenson archive. Ho does that one knob on top control the feed without hydraulic lock? Obviously it doesn’t so what is missing?

And one from the two French engineers who visited the engine at work, even more confusing:
10 April 2010 at 14:31 #50606
Jonathan Howes
Participant
@jonathanhowes93303
And four views of the Invicta unit. There seem to be two plug valves operated by square section heads implying a key in the hands of the driver, obviously regarded as a responsible job. What form of valve can be got in to the end of the ram pump to prevent its action given that there does not appear to be much room to install anything with no access cover visible?
10 April 2010 at 15:17 #50609
Jonathan Howes
Participant
@jonathanhowes93303
The engine was visited by the two french engineers, Coste and Perdonnet, while working on the Bolton and Leigh railway. Their description of the boiler feed goes (my translation…):

P, force pump. This draws water via a leather tube, from a barrel placed behind on a train T, and raised to the boiler by tube C.

A horizontal boiler feed tube is indicated by circle n’, q (my note; this places the feed lower than on other examples).

S’, the adjustable boiler feed valve. The piston rod of the force pumpis rigidly linked to the piston via a rod from the crosshead as shown in the figure.

So, still little clearer and what is that trycock doing on the vertical pipe just above the pump barrel?
11 April 2010 at 10:55 #50626
Jonathan Howes
Participant
@jonathanhowes93303
Thanks to KWIL for sending me a drawing of the Locomotion pump. I was wondering if a three valve system was at play here. I still don’t see how the feed rate is controlled however.
11 April 2010 at 15:29 #50631
Paul White 3
Participant
@paulwhite3
hi, a very interesting project . Could the answer to your question be a simple valve in the supply line that controls water into the pump?
12 April 2010 at 08:53 #50640
Jonathan Howes
Participant
@jonathanhowes93303
Paul,

This was what I was looking for at first, the problem is that the French reference (three posts back) clearly states that the valve S’ in the figure is an adjustable boiler feed valve. Elswhere in the french text this is clearly stated as being convenient for the location of the driver as it projects through a platform on the side of the boiler on which the driver stands. A bit awkward here as the Stephenson drawing shows the valve and platform on the left hand side of the boiler, the French text describes (but does not show) the platform to the left and the pump/valve to the right.

From other digging, feed pipe valves do not seem to appear on locomotives until the early 1830’s, LW was built in 1828 and is a very important locomotive being the first to employ expansive working of the steam, it was also the clear predecessor of the Rocket.

I am working on drawings for the model but I fear that the pump may remain “TBD” for a while yet.

Jon.

Edited By Jonathan Howes on 12/04/2010 08:55:40
12 April 2010 at 10:19 #50641
Paul White 3
Participant
@paulwhite3
Jonathan, If the valve” S “is for boiler feed, this would be a design for failure in the absence of some form of bye pass or restiction in the feed water by producing the hydraulic lock you mentioned in your earlier post ! Or am I missing something. You may have found the earliest use of feed water control. Pumps of this time had what looks like a valve lift control.

Paul.
12 April 2010 at 11:10 #50642
Jonathan Howes
Participant
@jonathanhowes93303
Paul,

You have me intrigued!

Firstly, the valve S was clearly for feed control as stated in contemporary references. I have also found a description of one of the Gurney Steam Carriages which shows a system whereby the control is to divert feedwater back to the tank, this is from before the period of the Lancashire Witch but it is possible that the valve S is there to bypass the upper clack and to allow a slug of water to oscillate between the pump and the boiler.

The valve lift control idea is interesting and is the part that intrigues me. The square headed shanks in the Invicta photographs may be just that, ie, some form of eccentric used to lift a clack open and prevent its action. Do you have any examples/drawings of valve lift control from around the right period?

Jon.
12 April 2010 at 12:35 #50646
Ian S C
Participant
@iansc
I’m not familia with steam engines paticulary this old, but would it be possible that the valve is in the form of a leather flap, I’v seen this in domestic supply pumps of 60-70 yr vintage and proberbly older. Ian S C
13 April 2010 at 09:56 #50660
Paul White 3
Participant
@paulwhite3
Jonathan,

                Sorry no. I thought that the impression came from information in “Ahrons” but

                having spent considerable time looking I can’t find the reference.

                I still feel that a device with one input and one output with set piston operation

                can only be controlled by:- 1, restriction of supply

                                                                  2, ability to hold open the feed- in valve

                                                             or 3, open outlet from cylinder to atmosphere to

                                                                      prevent a vacuum being formed.

   Paul.
13 April 2010 at 09:59 #50661
Paul White 3
Participant
@paulwhite3
sorry about the above posting ,I didn’t type it like that !

Paul
13 April 2010 at 21:15 #50672
Jonathan Howes
Participant
@jonathanhowes93303
Paul,

Thanks for the “Ahrons” tip-off. I think the quote that you may have been searching for is in the context of the Rainhill (as opposed to Stockton and Darlington) Rocket:

“One brass feed pump was fixed between the motion bars and boiler, and worked from the crosshead. The pump had mitre valves, the lift of which was regulated by snall spiral springs. A leather hose connected the copper suction pipe with the tender.”

This is actually surprisingly helpful since it shows that spiral return springs were in use, something I had assumed came later. This has clear importance for the inclined pump barrel with an in-line inlet clack valve since I was head scratching over how this could be made reliable without some form of internal spring.

Thanks again for the hint.

Jonathan.
3 August 2018 at 20:16 #365399
Malcolm Lippiatt
Participant
@malcolmlippiatt57337
Hi Jonathan

If you go to my thread on Lancashire Witch you can see I'm interested in creating a 3D model of The Lancashire Witch 1828 which in your thread in 2010 you stated that you were going to produce drgs of it. did you do that and if so would those drgs be available to the likes of myself.

I create these loco's from drgs or/and pictures available on the net but there seem very few available on the Lancashire Witch so at the moment I'm struggling, any help would be appreciated
4 August 2018 at 03:00 #365443
John Olsen
Participant
@johnolsen79199
I see that the above discussion on boiler feeds took place some time ago, but maybe for completeness I should mention that early American locos, from about the beginning up until injectors became common, usually used crosshead feed pumps controlled by a valve in the suction line. This is quite likely a feature that they copied from their English predecessors. I have somewhere a book about early American locos that discusses this feature, and it does seem odd that they persisted with it for so long, when a simple bypass arrangement would work so much better.

A pump controlled by the suction side will cavitate badly which tends to wreck the pump in short order…nevertheless they persisted with this arrangement for maybe 50 years or so. I know for instance that the Rogers 2-4-2 locomotives supplied to the New Zealand railways in 1877 came with a crosshead feedpump on each side. They were replaced with injectors quite quickly.

John
Author

Posts