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gas turbine anyone?

Started by mobile_bob, August 14, 2012, 01:40:36 AM

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mobile_bob


quinnf

Bob,

Linda's got several Big Leaf maples in her yard.  And you know what happens in the PNW in the appropriately named Fall season when the leaves fall and it rains, plastering the leaves all over everything.  Been thinking that a small lightweight gas turbine would make a dandy leaf blower!

Quinn

Henry W

#2
Back in 1984 I worked for a company in Latham N.Y.  called Turbo Systems International. That is exactly what we built. We used Pratt & Whittney, Allison and GE Turbines. If you think Detroit Diesels are loud you would be in for some surprise. The very first time I was near one of those while it was spinning up for startup I was very uncomfortable. Oh, A V-16 Detroit diesel powered compressor was used to operate the air motor to to spin it up.

Back than one of the GE turbines went for over 3 million dollars.

My department I worked in was in charge of retrofitting turbines to to spin MW gensets for Oil and Gas companies around the world. You want to talk about a gearbox :o At the time they were made in Sweden and over 7 feet tall. I don't remember how many gallons of oil the gearbox held but it was lots. Than talking about oil coolers for the turbine and gearbox. They were huge and 3 phase electric fans were used to push the air. Than talk about electric oil pumps for the turbine. There was always redundency built into these units so one can be serviced while the unit is operating. These electric oil pumps were operating before the turbine was spun up. The turbine shaft Bushings must be under pressure to float the shafts.

And the oil brand used for these units: Texaco Havoline

It does not seem so long ago because I still think about it quite often.

Henry

fabricator

I had to install some roof ventilators on what the power company called a peaker turbine, this thing would start up if the load on the grid got to a certain point, the thing was huge, there were automatic louvers in the walls, we had to wear double hearing protection (foam plugs and muffs) the entire time we worked there, they told us if the buzzer went off and the red lights flashed we had 60 seconds to get off the roof before the thing started up.
It started up once while we were there, luckily at lunch time so we were in the parking lot, but it was extremely loud 300 yards away, the LOUD buzzer goes off and the red lights flash then all the motorized louvers open and the pony engine winds up then the turbine spools up and drown's everything else out, pretty awesome.
It only ran for about an hour, we took a long break till it shut down.

Henry W

Yes it is something to experience. Double hearing protection is a must and still it does not help that much. The sound pressure goes through your whole body when we worked right next to them a few times while they run them up over 100% while testing them out before being passed and certified.

Henry

fabricator

Quite frankly that thing scared the hell out of me.

Henry W

#6
My very first time I was next to one (about 10 feet away from the turbine) for testing we were spinning it up and I felt like hiding in a bunker. The funny thing was they did not even put the fuel to it because it did not reach startup speed yet. When it finely lit and they started putting the load on it, I thought /*^ were all going to die. After the first few tests I got used to it. But with all the precautions taken your ears were ringing after testing. I am not kidding when the sound pressure and vibrations goes right through your entire body. It is almost to the point that your body feels like it cannot function properly. It feels like your body functions want to shut down. It's amazing for the size how many thousands of Hp. they produce.

Henry

fabricator

We were 300 yards away from the thing in the parking lot with the windows rolled up and you could feel it in your bones, and they strap these things to aeroplanes and fly around in the sky on em, how can they possibly make a motor mount strong enough to hold one to an aluminum or carbon fiber wing?

mobile_bob

the pins that hold the engines to the wings are the size of coke can's
they are made to shear if there is an out of balance condition that might take out a wing
they shear to drop the engine under such conditions.

yes those pins are to be frequently inspected, some over the years have had corrosion issues
and engine's have fallen off.

i think while in seattle i heard of a dc8 losing an engine,  and maybe an md80 or a 747

that ought to be interesting to be looking out the window and see an engine drop off!

doh!!!!

bob g

fabricator

Especially on that new Boeing dream liner, it's only got two about 12 feet in diameter, flying something that weighs several million pounds on one engine has got to be an adventure.

vdubnut62

Quote from: fabricator on August 18, 2012, 08:33:26 PM
Especially on that new Boeing dream liner, it's only got two about 12 feet in diameter, flying something that weighs several million pounds on one engine has got to be an adventure.

Adventure? Are you sure you don't mean "White Knuckle Ride"? ;)
Ron
When governments fear the people, there is liberty. When the people fear the government, there is tyranny -- Thomas Jefferson

"Remember, every time a child is responsibly introduced to the best tools for the protection of freedoms, a liberal weeps for the safety of a criminal." Anonymous

mobile_bob

awe its not that heavy

pan a flew the heaviest 747's that ever graced the skies and they weighed in at ~750klbs fully loaded, full of fuel.

i would expect the dreamliner to be in at around a half million pounds fully loaded, maybe 600k tops.

either way, i would rather be on a 747 short one engine than any twin engine job, the 747 was rated safe to carry passenger take off and landing with one dead engine, was certified to fly without passengers back to a service hub with two dead engines, however i wouldn't want to be along for either ride.

i like all the engines firmly attached, turning the same speed, putting out the same power, and not vibrating or making unusual noises

i am just funny that way i guess

bob g

Ronmar

Did a tour on a USCG polar class icebreaker and earned an Engineering Officer of the Watch(EOW) qual.  The polars run 3 P&W FT-24's that deliver 25,000 SHP each that I operated when on watch.  +1 on the double hearing protection.  They were in their own sound enclosures, but even in there, they were uncomfortable to be around at full power.  Breaking ice we burnt right around 1500 gallons per turbine per hour.  The reduction gearboxes would have trouble fitting in my living room.  Not too many jobs where you get to crack the throttles on 75,000 SHP.  Probably one of hte coolest I will ever have had.
Ron
"It ain't broke till I Can't make parts for it"

fabricator

No doubt about that, all that power at you finger tips, would be an awesome feeling.