STEAM ENGINE QUESTIONS.

[Industrial Toys]

I don't know how my Mom knew, but she told me several times, that you can't see live steam.

 

[Jstpssng]

If you listen to the video, you can hear a loud BANG every 5-6 seconds. That's steam hammer. Condensate has built up in the pipe to the point there's a water slug getting slammed down the pipe in a wave. The water runs back, forming a wave that blocks the steam and its again hurled down the pipe, drains back, plugs, is hurled, drains, plugs, hurls, drains, plugs, hurls.... eventually, in extreme cases, it can burst the pipe. If the steam pipe bursts, the steam reverts to normal water - violently expanding 1600 times its volume pretty much instantly. BOOM!

That also must be what causes the hammer in pipes of buildings which are heated with steam.

 

[Kernopelli]

1600:1 expansion ratio when it's let loose!

Great thread! I am a retired Stationary Fireman and have always found the properties of steam and it's generation to be fascinating. It's use as an energy source is ancient and goes back at least as far as Archimedes and is still the most viable energy source for many process and elec. generation applications today.

WATER expands by a factor of about 1600:1 when flashed to steam at atmospheric pressure.....hugely dangerous if uncontrolled! Rapid expansion from liquid to gas form is generally the bigger danger when compared to steam (a gas) being suddenly released to atmosphere where it quickly condenses back to a liquid. Not to play down the danger of sudden steam release or even "simple" leaks. I have seen minor steam leaks cut metal flanges or erode away concrete many times. High pressure steam is almost always invisible, so the "broom stick" method of leak detection is indeed a common method. Water hammer can be SCARY to say the least....even small slugs of water contacting steam can be quite violent and as seen in the video, can lead to catastrophic material failure.

 

[MossRoad]

I thought you were literally speaking of a steam hammer, and couldn't quite understand that.

Now, I get it.

But what of the flame and flash?

I went back and looked frame-by-frame and I think the orange flash is when the camera moves rapidly past a worker's orange vest. Looks like flames at full or even half speed.

 

[Egon]

If you listen to the video, you can hear a loud BANG every 5-6 seconds. That's steam hammer. Condensate has built up in the pipe to the point there's a water slug getting slammed down the pipe in a wave. The water runs back, forming a wave that blocks the steam and its again hurled down the pipe, drains back, plugs, is hurled, drains, plugs, hurls, drains, plugs, hurls.... eventually, in extreme cases, it can burst the pipe. If the steam pipe bursts, the steam reverts to normal water - violently expanding 1600 times its volume pretty much instantly. BOOM!

Might also be a steam trap venting.

 

[dadster4]

Might also be a steam trap venting.

It is steam hammer, but to clarify, the steam does not revert to water...the water in the line turns to steam when it is no longer under pressure due to a leak, break, or opened valve.
And steam traps do not vent to atmosphere or make more than a slight noise when activated.

 

[Egon]

It is steam hammer, but to clarify, the steam does not revert to water...the water in the line turns to steam when it is no longer under pressure due to a leak, break, or opened valve.
And steam traps do not vent to atmosphere or make more than a slight noise when activated.

Okay, I've been educated!

Others may follow this line of reasoning. Marmaduke Surfblow would probably agree!
[video]https://www.linkedin.com/pulse/whats-banging-steam-plant-part-1-traps-discharging-pumped-fidgeon[/video]

 

[MossRoad]

Might also be a steam trap venting.

Nope. It was hammer. We were shown this in class and the instructor had talked to some of the people involved.

 

[MossRoad]

It is steam hammer, but to clarify, the steam does not revert to water...the water in the line turns to steam when it is no longer under pressure due to a leak, break, or opened valve.
And steam traps do not vent to atmosphere or make more than a slight noise when activated.

You are correct on the part about water turning to steam when no longer under pressure.

We were told about cavitation in steam traps causing water hammer.

 

[MossRoad]

There's a good write-up on cavitation and hammer in this link...
- ITT-Residential and Commercial Water Solutions