Distance between water stops

This is a fairly specific question and relates to a 4-4-0T with BP 120 psi and 480 gallon tank running a semi suburban type service on a 15 mile line hauling 7 4-wheeled coaches with 4 intermediate stops and taking 1 hr 15 minutes.
The question is, how often would it need to take water?
The reason is , we are researching a long gone line but photographic evidence shows no signs of water tanks or water columns other than at the shed. My own opinion is that it could easily do a round trip without refilling and perhaps a second round trip also?
Later the line was extended 7 miles in the other direction, again no evidence of addition water being available. Two trains were in use.
I can provide more details if needed.

 

Which line?

It sounds like it isnt standard gauge/in the UK

 

Singapore, 1903, metre gauge. The original line ran from Fort Canning in the city, then alongside the Bukit Timah Road to a terminus at Woodlands where it connected with a ferry service to mainland Malaya. In 1907 an extension opened through the city and Chinatown. to the docks and Pasir Panjang. In 1923 a causeway opened across the Johore straits to connect it to the FMSR system in Malaya. It lasted until 1932 when much of it was replaced by a new deviation from Bukit Panjang direct to the docks at Tanjong Pagar. Not in UK but built by the British Government. And I assume there are people on here who will be able to help.

 

Would these Malaya/ Singapore locomotives be of similar size to those on the Isle of Man? I think Douglas to Port Erin is also 15 miles, so IOM operations might give a clue as to how often water top-up is needed. Some of the Welsh narow-gauge engines might also be comparable, or perhaps Terriers and P-tanks on the standard gauge. Was the Singapore line flat or hilly?

 

The IMR 2-4-0's of the 10-13 series run at 160psi and have 420g. tank capacity. As you say the South line is just over 15 miles each way and the locos have to take water at Port Erin and Douglas. When they do a short turn to Castletown 9 1/2 miles (as on some diners) they top up there before returning to Douglas. Obviously the steep 2 mile climb out of Douglas increases water consumption going South bound.
I can't see the locos mentioned in the OP doing a 30 mile round trip (let alone one of 44 miles) on one tankful even with only 7 4-wheelers in tow.
Ray.

 

I agree, it depends on the line and the gradients. As a comparison, Princess on the FfR is listed as 380 Gallons and you need to water at Port, TyB and BF but that is all uphill and then all downhill.

 

On the Corris, several sources mention Maespoeth (not historically a station stop) as being the only source of water for the locos. Is that credible? A trip down to Machynlleth mightn't have used too much water, but there was shunting to be done and the return trip, on unfavourable gradients as steep at 1:30 (officially!) would seem to be pushing the capacity of the small 0-4-2st locos. Surely there must have been a supply at Machynlleth?

Even pre-preservation, the Talyllyn (not exactly noted for over provision of anything!) had facilities at Pendre, Dolgoch and Ty Dwr.

 

An England Engine working about 40 tons and running a vac ejector is about 2/3rds empty after 7 miles of hard work. I think if this line was reasonably flat and didn't have to run an ejector it would be possible. I would also say though that running locos full to empty is something crews really don't like doing as there is no margin if something goes wrong.

Tim

 

On the Bluebell, you can - just - do a 22 mile round trip with a P class and 65 tons load, with 550 gallons of water. That is 11 miles mostly uphill in one direction, and mostly downhill coming back, two intermediate stops both of which involve a start uphill in one direction. I suspect the water consumption (just by inspecting the tanks, not by measurement) is probably about 300 gallons going up, 150 coming back, 100 spare. Vacuum braked.

Generally crews will choose to take water at the mid point, but you can just about do it without. Steam heating as well would probably put that level of endurance out of bounds, at least with any confidence.

For a metre gauge loco on what I suspect is a lighter load (7 four wheelers would be what? 40 - 50 tons?), doing 30 miles on 480 gallons sounds just about feasible, depending on what the gradients are.

Tom

 

On longer lines, to what extent is the quality of water at different locations an issue? I recall, many moons ago, being told the RH&DR preferred the quality of the water at New Romney, always seeking to minimise use of the facility at Hythe. Perhaps one factor contributing to the larger tenders adopted at much the same time superheating was reducing consumption per mile?