Steam pressure gauge- history?

The Bourdon tube gauge was patented in France in 1849 and Ashcroft in the US started manufacture in 1852..

Tom

AFAIK, the earliest ones were mercury columns or water columns. Then pretty soon Mr. Bourdon camed along with his little invention.

"Robert Swinney" wrote: AFAIK, the earliest ones were mercury columns or water columns. (clip) ^^^^^^^^^^^^^^^^^ Want to make yourself smile? Picture a water column attached to a steam boiler at 150 psi.* ________________________

• Water column about 300 ft tall.

High-pressure steam only came (in the 1800s) after James Watt, who abhored high-pressure steam because of the then considerable danger from boiler explosions. It took a long time for steel quality and boiler safety systems to mature enough that a 150 psi boiler was practical for general use.

Right on Joe! And didja ever wonder about all the tall smokestacks? Musta been where they hid the gauges.

Actually, the boiler pressure on those early coal lift systems was more like

-- Why do penguins walk so far to get to their nesting grounds?

If I remember correctly, the mercury gauge on Stephenson's Rocket, was on the outside of the stack!

Steve R.

Even though Watt hated high pressure steam, Oliver Evens in US was a proponent even before 1800, as were others around the world. Thus, from previous answers, I see that there was a gap of five decades between the development of high pressure steam and a decent gauge. Maybe that helps explain the number of boiler explosions :-) What I was just reading recently indicates pressures in 1820-1830 on western riverboats was about 30-40 psi, but someone (forgot who) had a 1850 psi system by around 1850. Sure hope he had a gauge on those! Anyway, that is why my question, and thanks for the answers, guys. Just what I was looking for. Now, how early were safety valves. Seems to me I remember reading that they were ealier, before 1800 by quite a bit. May well depend on what TYPE of safety valve, however.

Don,

You are gett>> >>

I saw something on the History Channel about the Sultana. Theory was the gross overload caused the boat to draw much more water than usual (duh!) .The deep draft over the muddy bars allowed mud to enter the water intakes and be pumped into the boilers. As the boilers get clogged with mud the pressure rises until BOOM!! Tom

But then, when did those safety valves come along?

I watched a video about steam locomotives the other day. The top of the firebox is normally below the water level, but if the water got low, this steel plate got uncovered. This would cause it to get red hot, and a boiler explosion would result. This would not be prevented by a relief valve or a pressure gauge. The sight glasses were the only protection.

This is a crown sheet explosion. The top of the firebox is called the crown sheet and if this becomes uncovered, or if the crownsheet stay bolts erode away, bad things happened.

Recently several people were killed at a fair in Ohio because a poorly maintained steam tractor blew up that way.

Jim

Not just locomotives. Steam tractors have the same design and issue.

The explosion usually does not occur while the engine is stationary. Its the lurching start or stop that splashes a quantity of water onto the red-hot steel, flashes it to steam and causes a pressure surge.