Welding on a tire rim

[T Red]

I'm sure we all know not to.  This is an interesting video as to what happens.  I had no idea. 

The delay on heavy equipment tires is surprising.  Worth a watch.

[T Red]

For those of you with dial up here's what happens.

They only welded on the rim for a few seconds.  A chemical reaction takes place in the actual walls of the tire after heat is applied called pyrolysis.  For a period of about 2 minutes the inside of the tire heated up, 500+ degrees F, and the pressure  increased just as dramatically.    This reaction continues and degrades the walls of the tire.  Eventually it explodes due to the pressure and weaken walls.

On heavy equipment tires it has taken 20+ hours after the initial heating for the explosion to occur. 

[Qweaver]

Watch a car race and notice that the brake discs glow red hot. Red heat = about 1200 deg F.  I've run several races that went to after sunset and I could see my brakes glowing red.  I wonder why we don't get the same thing happening?  I sure would not weld on a mounted tire rim after watching that.

[beenthere]

Hmmm?  Seems to be in the same category as heating a can of beans with the lid still in place. 

[D Hagens]

Hmmm?  Seems to be in the same category as heating a can of beans with the lid still in place. 

 So I take I wasn't the only one that did this as a kid.

[Slabs]

Hmmm?  Seems to be in the same category as heating a can of beans with the lid still in place. 

 So I take I wasn't the only one that did this as a kid.

Yep.  Them hot beans can also be classified as shrapnel.

[zopi]

Hmmm?  Seems to be in the same category as heating a can of beans with the lid still in place. 

Saw a dude heat beenie weenies in the rod oven once..when he opened the can all those angry little legumes jumped out and whooped him....little bean shaped burns all over his face....

[Coon]

Last fall we had a guy in the field next to us go under an overhead powerline with a tractor and grain cart.  He was heading over to the combine to top off his load of grain and all of a sudden BOOM al of the tires on both the tractor and grain cart blew along with grain flying in every direction.  It was investigated and found the powerline arc'd the grain cart due to being too close to the line.  The operator ended up in the hospital due to shocking of  nervous system.  He was observed and is ok.  The power company was sued for all damages as it was also found that the powerline did not meet the minimum height requirements.

Brad.

[footer]

You want to hear a good one. I worked about 16 years in industrial maintenance with a lot of heavy equipment, and more recently, 3 years as a tractor technician for a trucking company where I got a "michelin north america, truck tire technician" certification, and with over 20 years of working directly with heavy equipment and truck tires, this is the first time i have heard of this.

[Ianab]

I think thats what happens to airliners when they have to brake hard in an emergency. Over heats the brakes, they stop OK, then the tyres blow out from the heat.

Ian

[CLL]

Seen a guy in Vietnam heat a can of ham and lima beans with a little piece of c-4, everyone around him got to taste the beans. 

[dovetails]

Well that explains why 6 of the 8 tires on the truck crane I was running went POW when the boom brushed the overhead power line! Didn't feel a thing,would not have known what happened if another worker hadn't noticed the power line swaying.
Good thing the outriggers were down,or it would have been on it's side.

[Stan snider]

Footer, I'm the same as you. I had no idea this could happen and am far from a novice repairman. I have been aware of the power line contact blowing tires but figured it was arcing to ground.  That was a very good post T RED and could have saved someones life.   Stan

[easymoney]

i got a chuckle from some of the comments. will try to rember this if i am ever tempted to weld on a rim with the tire mounted. i can not think of why anyone would do it any way especially if the tire was inflated.

[Tom]

The times I've seen it done was when a mechanic welded a short length of pipe around the valve stem to protect it from off-road hazards.   It was tack welded and I guess the guy just got lucky.

[Warbird]

Which brings up the question that immediately popped into my mind the first time I saw this:  Has this always been the case with tires or is it just newer tires, due to new chemicals/process associated with making tires these days?

[dovetails]

Which brings up the question that immediately popped into my mind the first time I saw this:  Has this always been the case with tires or is it just newer tires, due to new chemicals/process associated with making tires these days?

In my case it happened about 23 years ago,and the tires were probably about 10 years old at the time, so I would say not just new tires. I have welded up some cracked rims in the past,but never with a tire on them as I welded both inside and outside of the rim to be sure it was solid. Also have welded big washers tocover valve stem holes on tractor rims where they rusted out,again, both sides of the hole,so no tire on the rim at the time.

[T Red]

Footer, I'm the same as you. I had no idea this could happen and am far from a novice repairman.

I'm right there with you.  I've worked with, around, and on equipment for the majority of my life and never heard about this.  That's why I posted, so get the word out. 

Now that it has been mentioned I remember seeing someone weld the pipe around the valve stem at least once with the tire on.  The Lord looks after us many times and we don't even know it. 

[thecfarm]

I welded stuff around all of my valve stems.But I had the tire off. I was afraid that I would melt or weaken the tire in that area.

[Tim/South]

I have also wielded covers to protect the valve stems.
I wonder if breaking the tire down but leaving it on the rim would be enough?

I have simply pulled the service truck up to the tractor, wielded and driven away.