Fluid filled tires and water crossing.

[CaveCreekRay]

Three tractors:

Tractor One Air-only tires. No additional weight on machine other than implements

This would be the worst case. Compressed air is denser than uncompressed air but the tires would still offer some negligible buoyancy in the water. A filled tire will float, but just barely. (An inner tube inflated to only 5 lbs generates much more buoyancy. Remember, it all has to do with density and water displacement.) This would be the lightest tractor.

Tractor Two Water-filled tires, no additional weights other than implements.

This would be the middle-weight tractor because the only additional weight would be the weight of the water in the tires above the water line. Remember, if you fill a tire with water, it will slowly sink.

Tractor Three Air-only tires with implement -PLUS addition weight amounting to the weight of the water that would fill the rear tires -mounted above the waterline.

This would be the heaviest vehicle because you would not suffer the loss of the weight of the submerged ballast water in the tires. All the weight would be on the tires.

I cannot follow your second question... Sorry.

Ray

 

[olthumpa]

Water, Rim Guard, Calcium and Foam all have different weights.
comparatively:

Water = 1
Rim Guard = about 1.3
Calcium = about 1.3
Foam = about 1.4 (whole tire is filled)

That being stated, if you are going to cross fast moving water of 2' or more with a small tractor regardless of what the tires are filled with, please put me in your Will.

 

[skeets]

Awww dont worry about it, if a green one can and orange one can too

https://youtu.be/ZRrHlcW8Md0?t=3

 

[CaveCreekRay]

"Warranty... what warranty?" (Nice Bayou snorkel there!)

Notice at 30 seconds the tractor starts bucking... The whole machine was scouring the muddy bottom and then bouncing on the next chunk of bottom. Had that been a fast moving stream of water, every bounce would have seen that machine move downstream. And once the machine starts moving laterally, you no longer have traction on the bottom nor directional control. Game Over.

 

[cerlawson]

Cave creek: I am about to give up, but will give the answer for the third one. Where the added weight (with no fluid in tires) is equal to the weight that otherwise might be in the tires filled only to the outside water level, the answer is they both are the same total tractor weight and both perform the same. That rear tire doesn't know the fluid was taken out and a chunk of steel hung on the back when it comes to its load on the ground under the tire. The bottoms of the tires carry identical loads on the ground in the water. However, the overall tractor effective weight is reduced by the weight of stream water displaced, whether filled (part way) or empty with equal weight hanging above water..

By the way out of the water they perform the same and weigh the same.

Next time you stop into the tractor place, pose this question to the most mechanically minded guys there.

To complicate it say that hung weight is really weights sitting (sliding along there) in the bottoms of the rear tires. Same result....Equal effect.

Have a nice day.

 

[cerlawson]

Ray:

A final post on this subject. Your examples 2 and 3 are reversed. The heaviest with respect to operating on land, in shallow water or deep water covering the tires completely is the one with filled tires. Once on the tractor in any position, in the tires, or out, submerged or dry, weight is weight, liquid, solid or air.

 

[cerlawson]

Ray: A suggestion to clear this up and with no higher up that decides.

This WEB site requires signing in under an assumed name, but they take anyone.

The members usually are experienced engineers, as am I.


This site deals with marine subjects.

http://www.eng-tips.com/threadminder.cfm?pid=321

 

[CaveCreekRay]

R,

I'll take your word on it! The difference in weight between #2 and #3 is negligible in overall percentage of vehicle weight.

The root of this thread was simply this: Would adding water to my tires help me get across a fast-moving river in 2' of water. As your concrete example exemplifies, things weigh differently under water. Why not a portion of a submerged tractor? Yes, on an absolute measure, it would add a small amount. But would that amount matter in the real world?

My point is simply this. A tractor or any vehicle facing moving water 2 feet deep is in imminent peril. You could see the knucklehead in the video clip above losing traction in static water. I am just trying to save a guy the cost of his machine, and maybe his life. We see all to many people washed away in vehicles here in AZ. The flooding in Texas has plenty of examples. As the good engineers specified with our town's heavy MRAP vehicle, you go a tiny bit past 2 foot and you run the risk of losing the vehicle -and it weighs several times what a tractor weighs.

Even on concrete crossings, you never know if the crossing is still there. Here's a road in my town. A few people were driving across it. Looks safe enough.

Here is what it looked like after the water went away... The concrete edge was under-scoured by three to four feet. That meant all that was holding the road edge up was air. In some places in town, the whole roadway had washed away. By that I mean the entire 10-15 ton piece of asphalt literally floated away in the rushing water. That represents an ENORMOUS amount of energy. A natural river bed suffers wild undulations during large water movement events. By the way, this roadway was flush with the downstream river bed before the flood. The vertical scour was four feet in areas. Imagine driving off the edge of that road edge...

This crossing looks the same with water running by... Turns out the water was 5 feet deep here. How can you tell? You can't.

Enough said.

Everyone have a great evening... and stay dry.

 

[cerlawson]

Hay Ray: No one can argue driving that water was dangerous. Scouring by rapid flows is damn hard to predict. In bridge foundation design a rough rule is that the depth of scour can be equal to the rise amount of the surface during flood times. So if the foundation depth is 6 feet below stream bed, the bridge can be destroyed if the water level during flood rises more than that. Who knows if that 6 feet is gospel, could be 8 or 10.

However one rule that saves a bunch of bridges is that no footings are used. Instead piles are driven to well below the estimated scour depth. Even bridges out in the country for overheads, no stream, piles generally are used. Reason is, the future may have trenches dug for one reason or another, such as communication cables and support can be affected by digging nearby.

On those dry runs you note with rare floods, they probably are not built to resist the possible scour events, since cost to prevent scour there is a lot more than fixing up the damage that you showed.

Oh yes, risking going thru any flooded area just may end up in a tragedy.

Bye

 

[p t farmer]

Wow! Such depth on this question. Amazing!
Here is my take, although a little more simple. Air like in any PFD "personal flotation device" helps things float in liquid. Same goes for blow up pool toys.
So a tire filled with air would want to float. A tire filled with water, or some combination of non-freezing liquid will not. My cousin and I both have filled tires. His is a two wheel drive Ford without weights and mine is a Kubota four wheel drive with rear wheel weights added. We both went in and came out without issue. Water was moving quick and was 2' plus deep. In the video if it will attach. We go down stream a little by design. It's not from any loss of traction. Even when the bush hog dips below the surface the tractor handles fine. I truly think the filled tires are a big part of this.
I'm not saying that it's not dangerous and something can't go wrong, but we each crossed 4 times without issue.
I will attempt to post my cousins crossing and will do mine once I get a copy from him.
Thank you all for your replies and interesting reading.

 

[CaveCreekRay]

pt,

Just be advised that your tractor wheel bearings are not marine "water proof" bearings. By getting in deep water you risk failure of the front wheel bearings at some point down the road as well water penetration into other parts of your tractor, like the differentials. In my case, the differential uses hydraulic fluid which would pump that moisture throughout the hydraulic system and, in doing so, make it very hard to get it all out.

Ray

 

[D2Cat]

Ray, Kubota is a light weight tractor, built that way for use in rice patties. Exhaust was designed to go horizontal or rotate 90deg. to stick up higher to eliminate water intake. Bell Housing had a drain plug to let water out. Designed to run in water and under water.

What did those Far Easteners do to keep their tractors operative?

 

[CaveCreekRay]

Rice paddies are 6" deep. That keeps the axles out of the wet and goo.

I am not so sure about using your tractor as a "submarine."

 

[CaveCreekRay]

Correction: American rice paddies are 6" deep. We have the advantage of laser-leveling and can save water by doing that. In the Far East, some paddies are 6 foot deep. Clearly they aren't driving through those either.

As far as the bearings are concerned, I just called the Kubota Dealer Service Center near me and he said the front axles are pretty secure on a "new" machine with good live seals. Anything exhibiting weep would be a concern. His big worry is any oil or hydraulic service inspection point. Those are not waterproof and will cause problems if submerged. He also cautioned about the hydraulic vent tube on the lower rear end area. It is a pathway for water and must not be submerged. He said water penetration of the hydraulic reservoir is a very expensive thing to resolve. Many don't know they are contaminated until the hydraulics start acting really sluggish. Bleeding the system he said is best done twice and even that doesn't get it all, every time.

Perhaps the models sold in the Far East are a little different than the ones they send us.

 

[skeets]

I dont know about them being 6 feet deep but I know of one that was waist deep

 

[CaveCreekRay]

The weird thing about rice growing is that the water only keeps the fast growing weeds at bay long enough for the rice to take over. Then, they drain the fields and the rice is usually harvested in dry conditions, at least here in the states.

I lived in Sacramento in the 80's. Home to US rice production.

Last year, out here in AZ, I did a private CCW class for a rice farmer from Sacramento, out here for the winter. After the paperwork was all done, he started showing me some of the equipment he used on his farm north of Sacramento. Hokey smokes!

It was all newer Deere equipment and the huge haulers (6-wheel dump trucks?) that capture the rice grains for transport to the mill cost nearly $200k. He owned 6 of those! Some of the specialized planting and harvesting equipment was way more expensive. From the size of it, you could see why you would want to harvest in dry conditions, even though it had high flotation tires. The planter plants in wet conditions but is fairly lightweight. It has to be towed by a tractor and the Deere he used was one of the larger ones also with specialized tires. The tires were almost 6 feet in diameter. I think he had three of those and they were several hundred K apiece.

Farming is unbelievably expensive! No wonder food costs have gone up. Thank God for all those with the initiative and drive to take that challenge on!

Ray

 

[Kingcreek]

This thread is still going?
I wonder if he made it across the water yet...

 

[CaveCreekRay]

KC,

You musta missed it.

 

[p t farmer]

Made it across fine. Having more trouble trying to figure out how to upload the video!

 

[p t farmer]

Thanks for the water warnings. I'll check fluids and intake locations for contamination.