Tourist lines

[Trainman203]

Keeping the crown sheet covered with water in steam engines is critical to prevent boiler explosions.  Those were unbelievably devastating.  One in San Antonio in 1912 killed a dozen  and s half in the neighborhood around the T&NO shops.  Others launched the boiler a quarter mile or more away while the running gear stayed on the track and kept rolling , being pushed by the trains momentum.  One thing for certain, everyone in the cab always died.

Steam engines were basically rolling bombs always trying to explode unless carefully monitored.  We forget this in the age of the relatively safe diesel.

[rogertra]

UK locomotives had lead fusible plugs in the roof of the firebox, several of them.  Actual explosions of boilers were almost unknown in the UK as were the melting of the fusible plugs.

The melting of the fusible plus permitted steam and water from the boiler to extinguish the fire.  It was dangerous to the crew as blowback through the firehole was a risk but it happened so rarely.

Hewison (1983)[22] gives a comprehensive account of British boiler explosions, listing 137 between 1815 and 1962. It is noteworthy that 122 of these were in the 19th century and only 15 in the 20th century.

Throughout the 20th century, two boiler barrel failures and thirteen firebox collapses occurred in the UK. The boiler barrel failures occurred at Cardiff in 1909 and Buxton in 1921; both were caused by misassembly of the safety valves causing the boilers to exceed their design pressures. Of the 13 firebox collapses, four were due to broken stays, one to scale buildup on the firebox, and the rest were due to low water level.

Cheers

[RAM]

Well the list I saw was 48 in the U.S.  Many of the locomotives in the U.S. also had the lead fusible plugs.  I am sure that 48 was a little low. 

[Trainman203]

http://colfa.utsa.edu/users/jreynolds/Tucker/exp1.html

[Terry Toenges]

Very interesting read. Thanks.

[Trainman203]

Back to tourist railroads.  Boiler explosions are not a thing of the distant past.  Makes me think twice about asking for a cab ride.

https://www.ntsb.gov/safety/safety-studies/Documents/SIR9605.pdf

[Len]

Boiler explosions are a factor in why many tourist lines started using diesels. After a steam tractor, which doesn't have near the inspection requirements of a steam loco, explosion at a fair a while back, the insurance companies jacked coverage rates on steam locomotives. In many cases to the point where it was either switch to diesels, or quit operating.

Len

[Trainman203]

Makes sense.  To the insurance company.

Steam excursions in our area were dropped after some kid slipped , chipped a tooth, and the attorney-aunt sued the railroad and the sponsoring fan club.

[Terry Toenges]

The report about the 1995 incident is quite an eye opener. It seems there were a lot of screw ups by the railroad. It makes a good point about the dwindling supply of people with first hand knowledge of steam locomotive care and maintenance. I never would have thought that the boilers had to be thoroughly cleaned out like that every month. It never occurred to me that they had to treat the water. There are so many things they have to check before they even take off.

[RAM]

The GETTYSBURG RAILROAD locomotive should not have been operated.  If you can't see how much water you have, you don't operate. 

[plas man]

Jeff - Water levels in the boiler makes sense and something I hadn't considered.

way back the Uintah Railroad , had 2 big (massive) 2-6-6-2 tanks , and whilst running on a uphill bunker first run the engineer noted that there water no water visible in the sight glass - due to the long boiler - both loco's was immediately returned to the shop's to be fitted with a second water feed dome , thus curing the problem .

https://www.google.co.uk/url?
sa=t&rct=j&q=&esrc=s&source=web&cd=20&cad=rja&uact=8&ved=0ahUKEwiZhMTl9ofcAhXGN8AKHRonBKgQFgh2MBM&url=https%3A%2F%2Fwww.republiclocomotiveworks.com%2Fuintah50.php&usg=AOvVaw2QsaSg7y8JhUpYY78nc-sl

[ebtnut]

If you read the report on the Gettysburg incident closely, the proximate cause was almost total blockage of one of the valves feeding the glass, which did allow some water to show in the glass, but it was not an accurate indication.  The engineer had needed to blow down the glass before operating the engine to assess the flow through the glass.  Because there was some water showing in the glass, the fireman believed he did not need to pump more water into the boiler. 

[Terry Toenges]

In reading the report, I couldn't help but think of the space shuttle where a simple thing like an o-ring malfunction caused a major disaster.