Here's what can happen when a traction tire falls off of a 1:1 scale locomotive:
Stuart
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Nothing?????
I don't think 1:1 locomotives have "traction" tires because the tires are steel, a reason they have sand. I would think if one came off (if they do), especially at speed, it would do damage to the locomotive. An interesting topic. Waiting to hear from the experts.
April Fool!
No traction tires on diesel locomotives. They all use Magne-traction. 😉
Curt
On steam locomotives the wheel thread replacements are heat shrunk on the wheel body, diesel locomotives the fractured or worn wheel, one piece, is pressed off the axle and new wheel pressed on. A significant wheel torque force would be required to separate the wheel thread from the wheel plate, if the wheel thread had a progressive crack that grew through the wheel thread cross section radially, and was not identified by inspection the crack can break through the wheel thread replacement, the frictional fit retention force would be lost, and the wheel thread ring would come off the wheel plate. As for diesel locomotive the wheels are cast or dye forged steel and have a condemning radial wheel limit, these wheels are hydraulically pressed on and off the axles, press on tonnages are recorded per AAR Standards. Wheel inspections are conducted per FRA Requirements. If my memory is correct to press on a 36 in wheel on the wheel axle the required about 140 tons. If a wheel fractured and broke into segments a derailment most probably would occur.
John Ochab posted:On steam locomotives the wheel thread replacements are heat shrunk on the wheel body, diesel locomotives the fractured or worn wheel, one piece, is pressed off the axle and new wheel pressed on. A significant wheel torque force would be required to separate the wheel thread from the wheel plate, if the wheel thread had a progressive crack that grew through the wheel thread cross section radially, and was not identified by inspection the crack can break through the wheel thread replacement, the frictional fit retention force would be lost, and the wheel thread ring would come off the wheel plate. As for diesel locomotive the wheels are cast or dye forged steel and have a condemning radial wheel limit, these wheels are hydraulically pressed on and off the axles, press on tonnages are recorded per AAR Standards. Wheel inspections are conducted per FRA Requirements. If my memory is correct to press on a 36 in wheel on the wheel axle the required about 140 tons. If a wheel fractured and broke into segments a derailment most probably would occur.
I have never seen the components on a steam locomotive referred to as "wheel thread" and "wheel body".
First off, wheels have treads, not threads.
Secondly, for the steam locomotive components, the correct nomenclature is "tires" and "wheel centers".
I was just going to say that.
And yes, tires can come off the wheel centers on a steam locomotive in operation, often because the tires become overheated from excessive braking.
smd4 posted:...And yes, tires can come off the wheel centers on a steam locomotive in operation, often because the tires become overheated from excessive braking.
Which is why a good steam engineer NEVER uses the engine brake when running over the road pulling a train.
juniata guy posted:No traction tires on diesel locomotives. They all use Magne-traction. 😉
Curt
All except the Belt Railway of Chicago. Or did they convert to solid wheels?
Why reply to postings, some of the Forum members should be in Washington, they know everything!!!!.
John Ochab posted:Why reply to postings, some of the Forum members should be in Washington, they know everything!!!!.
Um...what?
Stuart, I couldn't see your photo. Was it a steam engine sitting disabled with a tire or tires off of the driver(s)?
Belt Railway of Chicago was unique as far as I know, in specifying diesel locomotive wheels with tires on all their locomotives built from the late 1930's until at least 1975, maybe longer. They believed that it was the most economical answer for their particular operation. And they must have used a lot of engine braking, as they switched all day. I don't know how they made it work, but they did.
In my young adulthood, I waited for an hour to photograph their pair of Alco Century units (with tires) at a big crossing in Chicago. After an hour in the sun, I headed over to a grassy area under a tree, and a black cloud of the most vicious mosquitoes I have ever encountered rose up and attacked me. Fierce little fellows, they were. I was a naíve California boy, from country where rain is a novelty and insects are sparse, and that was a lesson in MIdwest etymology. No photo . . . too busy retreating, swatting, and scratching.
So . . . Stewart . . . about the photo . . . ?
Number 90 posted:Stuart, I couldn't see your photo. Was it a steam engine sitting disabled with a tire or tires off of the driver(s)?
Belt Railway of Chicago was unique as far as I know, in specifying diesel locomotive wheels with tires on all their locomotives built from the late 1930's until at least 1975, maybe longer. They believed that it was the most economical answer for their particular operation. And they must have used a lot of engine braking, as they switched all day. I don't know how they made it work, but they did.
In my young adulthood, I waited for an hour to photograph their pair of Alco Century units (with tires) at a big crossing in Chicago. After an hour in the sun, I headed over to a grassy area under a tree, and a black cloud of the most vicious mosquitoes I have ever encountered rose up and attacked me. Fierce little fellows, they were. I was a naíve California boy, from country where rain is a novelty and insects are sparse, and that was a lesson in MIdwest etymology. No photo . . . too busy retreating, swatting, and scratching.
So . . . Stewart . . . about the photo . . . ?
Tom,
The photo is of a B&M 4-6-0 which broke the main axle on the left side. The main driver is laying against the ground, with the main and side rods bent, but still attached. Also, the air pump has been knocked loose and is barely hanging on the side of the boiler.
Stuart
Well, why not re-post the photo in a manner that everyone can see it?
PRRMP54 posted:Well, why not re-post the photo in a manner that everyone can see it?
How? I used "insert/edit image" using a jpg file.
Nick Chillianis posted:John Ochab posted:On steam locomotives the wheel thread replacements are heat shrunk on the wheel body, diesel locomotives the fractured or worn wheel, one piece, is pressed off the axle and new wheel pressed on. A significant wheel torque force would be required to separate the wheel thread from the wheel plate, if the wheel thread had a progressive crack that grew through the wheel thread cross section radially, and was not identified by inspection the crack can break through the wheel thread replacement, the frictional fit retention force would be lost, and the wheel thread ring would come off the wheel plate. As for diesel locomotive the wheels are cast or dye forged steel and have a condemning radial wheel limit, these wheels are hydraulically pressed on and off the axles, press on tonnages are recorded per AAR Standards. Wheel inspections are conducted per FRA Requirements. If my memory is correct to press on a 36 in wheel on the wheel axle the required about 140 tons. If a wheel fractured and broke into segments a derailment most probably would occur.
I have never seen the components on a steam locomotive referred to as "wheel thread" and "wheel body".
First off, wheels have treads, not threads.
Secondly, for the steam locomotive components, the correct nomenclature is "tires" and "wheel centers".
Nick, you'll have to excuse John, he's the retired Chief Mechanical Officer of the South Shore so he only knows Little Joes, Juice Jacks and electricity 
(Yeah I know - sadly South Shore (CSS, the freight South Shore Railroad, not NICTD South Shore) is all dieselized and has been for decades)
Stuart posted:PRRMP54 posted:Well, why not re-post the photo in a manner that everyone can see it?
How? I used "insert/edit image" using a jpg file.
Is your image hosted on a platform like Snapfish? You can't just insert the image from your home computer.
If it's from the Internet, you can just post the link, and we can go see it ourselves.
smd4 posted:Stuart posted:PRRMP54 posted:Well, why not re-post the photo in a manner that everyone can see it?
How? I used "insert/edit image" using a jpg file.
Is your image hosted on a platform like Snapfish? You can't just insert the image from your home computer.
If it's from the Internet, you can just post the link, and we can go see it ourselves.
Steve,
The image is visible in my original post. It's a jpg file that I copied from my email (a friend sent the original to me), and I used from the tools on this site "Insert/edit image."
Stuart
Whoa! That's a little more than loss of a tire.
Thank you. It looks like the wheel came off of the axle or the end of the axle sheared off. Interesting picture.
I think I've posted this item somewhere else on the OGR forum but since we are talking about locomotive tires and things that can happen to them I thought it would be worth posting this (again?).
"#276, a Baldwin, had just come back from the shops in Salida, completely overhauled. She had new, full tires. The first engineer who took her out on a breaking-in run said she was the easiest riding locomotive he had ever operated. Shortly after the break-in she slipped a tire. She was towed to Grand Junction where the tire was removed and a new one ordered. It arrived, was heated cherry red, slipped over the wheel, and allowed to shrink into place. When 276 when back into service she rode so rough that the crew couldn't stay in the cab and they refused to take her out again.
The master mechanic had her wedges dropped to make sure none of them were stuck. She was reassembled and the second crew who took her out had the same complaint as the first. Everything possible was done to improve her riding qualities. Different officials from the mechanical department went out with engine crews and tried to find the trouble. This went on for about a month. Then I was called to run her. Those Grant 200's I'd fired between Salida and Pueblo rode like Pullmans in comparison to this little Baldwin.
She rode so rough it seemed she would shake every pipe and fixture off her boiler. It was impossible for a crew to stay in her cab. The faster you went the rougher the ride. As I was coming back after my first exhausting ride I had an idea. When I got to Grand Junction I headed straight for the roundhouse and the master mechanics office.
I walked in and said," I think I know what's wrong with #276. I think she's got one wheel larger, or smaller, than the others."
"Bosh", snorted the master mechanic. "That engine came from the backshop with all new tires and the one she slipped was replaced from stock. It's exactly the same size as the others."
"Maybe you're right," I agreed. "But did you try calipering it?"
"I don't think so. I'll do that right this minute just to convince you you're having pipe dreams."
He led the way outside. That one tire was a half inch larger that the others! When it was turned down to exact size and replaced, the little 276 was once more the best-riding engine we had."
From Little Engines and Big Men-Lathrop
Axle wrung off, Hot Box.
Scene: A neat frame house not far from the B&M Roundhouse
A Locomotive Fireman enters the home through the mud room attached to the back porch. He is covered in dirt.
Fireman: "Honey, I'm home."
Wife (from kitchen): "How was your trip, Dear?"
Fireman: Oh, it was okay. The engine broke an axle and derailed. I got sprayed with ballast and dirt, and fell out of the cab, but otherwise it was a pretty good trip."
"spare the rod and spoil the wheel"
What about older electric motors?
