Steam locomotive performance vs maintenance schedules

[70014IronDuke]

One of the characteristics of steam traction was the number of variables affecting performance - which included the footplate team skills, coal quality and locomotive maintenance standards (which are massive variables when compared to both diesel and electric parameters).

One major maintenance item was boiler washouts: locomotives had to be stopped every 10 ? days or so, allowed to cool down and have their boilers treated to remove scale - solidified calcium salts from the boiled off water - from the tubes, which impaired the heat transfer from the (very) hot tubes to the water in the boiler.

My question: What was the typical difference in loco performance fresh off a boiler washout to one at the end of the cycle? Was it measurable? Did planners have to reckon on point to point timings of - say 12 minutes with a good locomotive to 14 minutes over a certain section, so time it for 13 minutes?

Did the drivers quickly realise that a loco with scaled up tubes was a poor steamer, and report the engine for a boiler washout, regardless of the standard schedule?

Or was this variable typically 'lost' in the cacophony of other variables, from worn piston rings throught poorly trained fireman to bad coal etc?

 

[6Gman]

One of the characteristics of steam traction was the number of variables affecting performance - which included the footplate team skills, coal quality and locomotive maintenance standards (which are massive variables when compared to both diesel and electric parameters).

One major maintenance item was boiler washouts: locomotives had to be stopped every 10 ? days or so, allowed to cool down and have their boilers treated to remove scale - solidified calcium salts from the boiled off water - from the tubes, which impaired the heat transfer from the (very) hot tubes to the water in the boiler.

My question: What was the typical difference in loco performance fresh off a boiler washout to one at the end of the cycle? Was it measurable? Did planners have to reckon on point to point timings of - say 12 minutes with a good locomotive to 14 minutes over a certain section, so time it for 13 minutes?

Did the drivers quickly realise that a loco with scaled up tubes was a poor steamer, and report the engine for a boiler washout, regardless of the standard schedule?

Or was this variable typically 'lost' in the cacophony of other variables, from worn piston rings throught poorly trained fireman to bad coal etc?

There is no way running times could be adjusted; the timetable is the timetable! And would pretty much tie up to your last sentence. Timings based on a typical loco, in typical condition, and under typical weather etc.

If time was lost the crew could put it down to "condition of loco" which might, or might not, be accepted. In part the judgement might well reflect the past record of said driver and/or fireman. Shall we say, some traincrew quite liked overtime ...

 

[70014IronDuke]

There is no way running times could be adjusted; the timetable is the timetable! And would pretty much tie up to your last sentence. Timings based on a typical loco, in typical condition, and under typical weather etc.

If time was lost the crew could put it down to "condition of loco" which might, or might not, be accepted. In part the judgement might well reflect the past record of said driver and/or fireman. Shall we say, some traincrew quite liked overtime ...

I'm talking about planning the timetable, not adjusting it to fit the locomotive on the day. I realise that's never been done (well, maybe in 1830 or some such).

 

[Clarence Yard]

Timings were done on the basis of the locomotive being in good, not average condition.

Washing out periodicities were worked out on the basis of keeping the boiler in good condition throughout the period to the next washout. It wasn’t really a major maintenance item but it was a repetitive task that had to be done on time, rather like the periodic X day exam regime that BR had for all its steam locos.

 

[Taunton]

Washing out intervals were varied according to local experience, down to both usage and water quality. An extreme was the LT&S from Fenchurch Street to Southend, well known for the worst water quality on BR, which despite various attempts at water treatment was never got to grips with. Did read that the loco stud allocated was about 15% over what typically might be provided elsewhere, and a significant proportion were washing out on any given day. The Standard 80xxx tanks transferred to the Western Region in 1962 on the LT&S electrification were appalling steamers, and hardly used.

 

[Clarence Yard]

The 80XXX tanks that went to the WR in mid 1962 were overdue shopping (which the ER weren’t going to pay for) and spent time in store both on ER and WR before they were put through Crewe in 1962/3.

They then went to Wales and most got transferred to LMR with their sheds in December 1962, the remaining six lasting in West Wales until 1963/4 when they went to SR/LMR.

Another bad area for washing out was on the Isle of Wight - the O2 tanks were on a 5 day washout cycle at one time.

 

[Wilts Wanderer]

Another bad area for washing out was on the Isle of Wight - the O2 tanks were on a 5 day washout cycle at one time.

Presumably chalky water isn’t ideal for boilers?

 

[Harvester]

Washing out periodicities were worked out on the basis of keeping the boiler in good condition throughout the period to the next washout. It wasn’t really a major maintenance item but it was a repetitive task that had to be done on time, rather like the periodic X day exam regime that BR had for all its steam locos.

A4 60027 worked between Kings Cross and Edinburgh on ’The Elizabethan’ and the weekend equivalent, for 46 consecutive days in 1960 (22/6/60-6/8/1960).That is 393 miles hard running a day! How was time ever found to slot in the engine’s boiler maintenance during that period?