water injection /goodall valves
taperpin
Lots of steam loco owners now use these valves to add water while running,,but there are drawbacks to them and one or two makers do not offer them for good reasons.
I have now had 2 locos in 1 week with collapsed flues.caused by running dry and then pumping water into ahot boiler..instant overpressure, and the overheated flue bulges inwards.
This is an expensive and difficult repair and In most cases a new boiler is better than repair,unfortunatley the only symptom is that the burner wont light off ,or is very difficult to get lit.Nothing is visible externally.
This reinforces the rule of "see the loco in steam" before parting with money One came from Ebay theother was aprivate sale, at distance.
Water Injection valves are very useful but I would suggest the fitting of either an Electronic water level indicator or gauge glass..and close attention when driving!
zubi
Gordon, that is a very good warning! In principle, the same applies to hand pumps, except that if there is a hand pump on the loco, it is much easier frequently to add a little bit of water and maintain the water level. With water injection/Goodall valves, operators (including myself) tend to run for prolonged periods of time before pumping water. It is simply somewhat more awkward to use the bottle and unless one holds it in the hand all the time, one has to locate it again and again... But I think that the main problem is that our water gauges are extremely unreliable, the only working solutions that I have seen are:
1) Frank S/Beck round window type
2) new style Roundhouse rectangular window
Best wishes, Zubi
Shrek`s Donkey
Hi Gordon and all.
I bought my goodall valve from Gordon, and it works fine, but I must say I do wonder if anything that I am doing with using the valve, could be dangerous for my loco (Edrig) or not. This is my usual pattern....
Run for 10 mins....
stop...
turn off burner....
refill gas to full again...
relight burner...
then slowly add approx 20-30 pumps of the water bottle through the valve. Note, my sprayer doesn`t pump very much with each squeeze. To be honest, never measured exactly.
Once pressure is reached, take off again....
After another 10 minutes has passed (20 mins in total) i then give another 20 odd pumps of the bottle to ensure there is enough water in the boiler.
So all in all, by refilling with gas at the 10 minute mark, it is extending the Edrig`s overall run by up to an extra 10 minutes or so than usual.
Can there be any risk by over filling the boiler? Or is there any sort of simple way that you know you can be safe, whilst operating "blind" in regards to the boiler?
johnsaintjim
Caradoc (same as Edrig?) takes about 200 ml from empty and Lawley about 250. I then take 30 ml out before lighting.
I count the pumps too but it's useful to watch the level on the bottle. I pump 50 to 100 ml at a time.
As for overfilling, if you do, the water squirts out of the safety valve. I reckon the pressure of the filler bottles must be around 100 psi, so easily enough to overcome the safety valve.
Once you have overfilled, you will have the joy of water and oil everywhere for a while as it squirts up and down the chimney and out past the glands all over the loco, onto you, your stock and buildings, your visitors and the surrounding area, etc, etc. . At least we are not at risk of bending and breaking large bits like the full size ones.
If it's really full, it might be worth opening the level tap to drain a few ml out so you don't have quite so much priming.
By the way, if you want to stay in steam for longer, it seems a good idea to fill the oiler as well. To do this, I shut the regulator, open the drain tap at the bottom, open the regulator and squirt the sludge out of the bottom. Close the regulator and drain tap, take the top off and fill the oil as usual.
This is all for Accucraft. Not sure about Roundhouse as I don't have one.
--------------------
Graham
brianthesnail96
And if you do run out of water, turn the gas off straight away and leave well alone until thoroughly cooled- no harm done. It's only an issue if you a.) don't notice and leaves the gas on, in which case you have a very short attention span and really aren't cut out for live steam or b.) put more water in before it's cold.
I've managed to run Tag's Edrig out of water so speak from experience...
--------------------
Matt:
zubi
That's exactly right and this 'a + b' is what Gordon is talking about. There is no problem if you add water to the boiler if there is still some water in it. The problem may happen if the boiler runs dry and the flue becomes plastic (soft) from overheating. Then if you add water, it will very rapidly boil, creating a shock of pressure (essentially an explosion) which may flatten or even fracture your softened flue. The Young's modulus of copper, physically describing its stiffness, is almost flat (constant) up to 100 degrees Celsius but then it curves down more and more rapidly, at 400 Celsjus it is half its value. Such temperature is not impossible locally in an overheated boiler, in fact adiabatic flame temperature of butane burning in air is almost 2000 Celsjus so you can melt the flue even before damaging it by adding water... Although the solder will probably give up first;-)... Best, Zubi
brianthesnail96
Quite so- I was just trying to make it sound less scary for any "newbies" out there. It's not a big problem!
--------------------
Matt:
minimans
As with all things mechanical service and attention to what your doing is always required! these thing's 'aint turn the knob and forget...........................And they 'aint suicide bomb's either it won't go off bang it will just hurt your wallet..................
--------------------
Paul
Shrek`s Donkey
Well it sounds like I must be operating my loco at a safe level then. I have never once run out of water, and I have never once seen water coming out of the safety valve when refilling, so it sounds like I should be ok to carry on the way I`ve been doing it.
Cheers
taperpin
Lots of steam loco owners now use these valves to add water while running,,but there are drawbacks to them and one or two makers do not offer them for good reasons.
I have now had 2 locos in 1 week with collapsed flues.caused by running dry and then pumping water into ahot boiler..instant overpressure, and the overheated flue bulges inwards.
This is an expensive and difficult repair and In most cases a new boiler is better than repair,unfortunatley the only symptom is that the burner wont light off ,or is very difficult to get lit.Nothing is visible externally.
This reinforces the rule of "see the loco in steam" before parting with money One came from Ebay theother was aprivate sale, at distance.
Water Injection valves are very useful but I would suggest the fitting of either an Electronic water level indicator or gauge glass..and close attention when driving!
zubi
Gordon, that is a very good warning! In principle, the same applies to hand pumps, except that if there is a hand pump on the loco, it is much easier frequently to add a little bit of water and maintain the water level. With water injection/Goodall valves, operators (including myself) tend to run for prolonged periods of time before pumping water. It is simply somewhat more awkward to use the bottle and unless one holds it in the hand all the time, one has to locate it again and again... But I think that the main problem is that our water gauges are extremely unreliable, the only working solutions that I have seen are:
1) Frank S/Beck round window type
2) new style Roundhouse rectangular window
Best wishes, Zubi
Shrek`s Donkey
Hi Gordon and all.
I bought my goodall valve from Gordon, and it works fine, but I must say I do wonder if anything that I am doing with using the valve, could be dangerous for my loco (Edrig) or not. This is my usual pattern....
Run for 10 mins....
stop...
turn off burner....
refill gas to full again...
relight burner...
then slowly add approx 20-30 pumps of the water bottle through the valve. Note, my sprayer doesn`t pump very much with each squeeze. To be honest, never measured exactly.
Once pressure is reached, take off again....
After another 10 minutes has passed (20 mins in total) i then give another 20 odd pumps of the bottle to ensure there is enough water in the boiler.
So all in all, by refilling with gas at the 10 minute mark, it is extending the Edrig`s overall run by up to an extra 10 minutes or so than usual.
Can there be any risk by over filling the boiler? Or is there any sort of simple way that you know you can be safe, whilst operating "blind" in regards to the boiler?
johnsaintjim
Caradoc (same as Edrig?) takes about 200 ml from empty and Lawley about 250. I then take 30 ml out before lighting.
I count the pumps too but it's useful to watch the level on the bottle. I pump 50 to 100 ml at a time.
As for overfilling, if you do, the water squirts out of the safety valve. I reckon the pressure of the filler bottles must be around 100 psi, so easily enough to overcome the safety valve.
Once you have overfilled, you will have the joy of water and oil everywhere for a while as it squirts up and down the chimney and out past the glands all over the loco, onto you, your stock and buildings, your visitors and the surrounding area, etc, etc. . At least we are not at risk of bending and breaking large bits like the full size ones.
If it's really full, it might be worth opening the level tap to drain a few ml out so you don't have quite so much priming.
By the way, if you want to stay in steam for longer, it seems a good idea to fill the oiler as well. To do this, I shut the regulator, open the drain tap at the bottom, open the regulator and squirt the sludge out of the bottom. Close the regulator and drain tap, take the top off and fill the oil as usual.
This is all for Accucraft. Not sure about Roundhouse as I don't have one.
--------------------
Graham
brianthesnail96
And if you do run out of water, turn the gas off straight away and leave well alone until thoroughly cooled- no harm done. It's only an issue if you a.) don't notice and leaves the gas on, in which case you have a very short attention span and really aren't cut out for live steam or b.) put more water in before it's cold.
I've managed to run Tag's Edrig out of water so speak from experience...
--------------------
Matt:
zubi
That's exactly right and this 'a + b' is what Gordon is talking about. There is no problem if you add water to the boiler if there is still some water in it. The problem may happen if the boiler runs dry and the flue becomes plastic (soft) from overheating. Then if you add water, it will very rapidly boil, creating a shock of pressure (essentially an explosion) which may flatten or even fracture your softened flue. The Young's modulus of copper, physically describing its stiffness, is almost flat (constant) up to 100 degrees Celsius but then it curves down more and more rapidly, at 400 Celsjus it is half its value. Such temperature is not impossible locally in an overheated boiler, in fact adiabatic flame temperature of butane burning in air is almost 2000 Celsjus so you can melt the flue even before damaging it by adding water... Although the solder will probably give up first;-)... Best, Zubi
brianthesnail96
Quite so- I was just trying to make it sound less scary for any "newbies" out there. It's not a big problem!
--------------------
Matt:
minimans
As with all things mechanical service and attention to what your doing is always required! these thing's 'aint turn the knob and forget...........................And they 'aint suicide bomb's either it won't go off bang it will just hurt your wallet..................
--------------------
Paul
Shrek`s Donkey
Well it sounds like I must be operating my loco at a safe level then. I have never once run out of water, and I have never once seen water coming out of the safety valve when refilling, so it sounds like I should be ok to carry on the way I`ve been doing it.
Cheers