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Re: Blower

Posted: Tue Nov 14, 2017 6:25 pm
by Fred_V
Yeah Bill, that's the problem with getting older. You start leaking from places that didn't leak before!!!

Re: Blower

Posted: Tue Nov 14, 2017 7:41 pm
by Bill Shields
actually it's more of leak when you don't want it to......

Re: Blower

Posted: Tue Nov 14, 2017 8:43 pm
by Builder01
Thank you Bill, my point exactly. As I said, putting compressed air in a boiler to run the built in blower is not going to shorten the life of the boiler in an amount that any one can measure.

David

Re: Blower

Posted: Tue Nov 14, 2017 8:54 pm
by Marty_Knox
Builder01 wrote:Thank you Bill, my point exactly. As I said, putting compressed air in a boiler to run the built in blower is not going to shorten the life of the boiler in an amount that any one can measure.

David
It certainly will on a steel boiler! But there is no reason to put compressed air into the boiler to run the blower. Run the blower line outside to a tee before it goes into the smokebox. Attach a valve and an air fitting to the tee, shut off the blower valve on your turret, and run the blower on house air.
That is how every full size locomotive I've worked on is set up.

Re: Blower

Posted: Tue Nov 14, 2017 9:04 pm
by Builder01
It makes sense not to put compressed air into a full size locomotive. The "receiver" is so large, it would take forever to get enough pressure to run the blower. As for shortening the life of a boiler, how will putting air into a boiler that already has air and water in it, hurt it?

David

Re: Blower

Posted: Fri Nov 17, 2017 8:41 am
by Marty_Knox
Builder01 wrote:It makes sense not to put compressed air into a full size locomotive. The "receiver" is so large, it would take forever to get enough pressure to run the blower. As for shortening the life of a boiler, how will putting air into a boiler that already has air and water in it, hurt it?

David
I'm sorry you don't understand or agree with the point I'm trying to make. Putting compressed air in a boiler while firing it up greatly accelerates corrosion, specifically oxygen pitting. Water absorbs oxygen, with compressed air there is far more oxygen to combine with the water.
I built a replacement boiler for a Ten Wheeler where the original one had failed after 2 seasons running. It was an oil burner and the owner filled the boiler with compressed air to start up. It had steel tubes - they had many small holes that looked like they were drilled in.

Re: Blower

Posted: Fri Nov 17, 2017 9:14 am
by makinsmoke
The Santa Fe had a valve shutoff just upstream of the steam firing manifold.
A line from a valve below and in front of the cab went into the firing manifold.

The shop would close the steam input valve and attach shop air to the outside connection, providing air (heck they could have been using shop steam!) to both the blower and atomizer, as well as the several blowout lines.

Once the engine had enough boiler pressure they would shut off and disconnect the air (or steam), and open the steam supply valve to the firing manifold.

There is a thread here somewhere with photos...

Re: Blower

Posted: Fri Nov 17, 2017 10:10 am
by Fender
Builder01 wrote:It makes sense not to put compressed air into a full size locomotive. The "receiver" is so large, it would take forever to get enough pressure to run the blower. As for shortening the life of a boiler, how will putting air into a boiler that already has air and water in it, hurt it?

David
If you use a boiler treatment with sodium sulfite in it (and you should with a steel boiler) then there will be little or no dissolved oxygen in the boiler water. If the boiler is then stored for a period while full of treated water, the sodium sulfite will continue to combine with (and neutralize) the oxygen from any air entering when the steam condenses.

Re: Blower

Posted: Wed Nov 29, 2017 6:47 pm
by Phil Tucker
One disadvantage of firing-up with compressed air is that every live steam track seems to have a different fitting on the end of their hose. Since there's no standardization you have to carry around an assortment of fittings in your toolbox, and piece together a working combination "on the fly."

Re: Blower

Posted: Wed Nov 29, 2017 7:17 pm
by John_S
I use both methods: an electric fan (furnace blower) and compressed air so I'm covered wherever I fire up. I hid a needle valve under the cab which I can screw in a standard male quick disconnect fitting. The copper line ties into the blower line to the smokebox.

Some folk's fans are louder than any air compressor -- you've heard them. When they finally switch over to steam and turn the fan off everyone claps.

Re: Blower

Posted: Thu Nov 30, 2017 11:00 am
by NP317
Referring to Marty Knox's discussion of dissolved oxygen in the boiler water, and the damage it can do, I have developed a steam-up process that decreases possible oxygen damage:
During steamup I leave a valve open on top of the steam dome. I let steam blow out for several minutes after the water boils. This is supposed to allow oxygen to escape before pressure build up. I learned this process years ago from operators at the Univ. of Washington steam plant. I'd be interested in Marty's (or anyone's) opinion of this procedure.
~RN

Re: Blower

Posted: Thu Nov 30, 2017 11:47 am
by DianneB
I picked up a small equipment blower with a metal fan from a local surplus house for a couple of dollars and mounted it on top of a tin can that fits over my stack. The motor shaft was long enough I was able to raise the motor 1/2" above the blower housing on spacers just to isolate the motor a little more from the heat. It is whisper quiet and only draws a few Watts. After steaming up, the motor is still cool enough to touch with your fingers.

When I had a 1/2 scale coal-fired traction engine, I made up a blower like Fred V posted on Page 2 - it worked excellent as well.