Tires Air Leaking Out of Wheel Rim Clamps on Mahindra 5555

[CincyFlyer]

Pyrolysis.
Excellent chance you壇 be dead wrong.

Hmmm. I'd get the tire out of harm's way, clean both sides of where the crack is, and weld it with the proper filler and technique, spray paint it, and expect it to hold 30 PSI, forever. There is no chance for pyrolysis. It wouldn't even be a disaster if a lug pulled out; it would just hiss. The tire coming off or apart is by far the greatest danger. Unless the wheel is made with defective steel, it's simply not going to catastrophically fail.
It wouldn't be the first low-pressure (under 200 psi) "vessel" that I've welded (I made some aluminum and steel air tanks for air shifters on drag race bikes, and some accumulators. Some people used PVC for race bike shifter tanks!), and I tested those at many times the working pressure using hydraulic fluid.

 

[RickB]

Hmmm. I'd get the tire out of harm's way, clean both sides of where the crack is, and weld it with the proper filler and technique, spray paint it, and expect it to hold 30 PSI, forever. There is no chance for pyrolysis. It wouldn't even be a disaster if a lug pulled out; it would just hiss. The tire coming off or apart is by far the greatest danger. Unless the wheel is made with defective steel, it's simply not going to catastrophically fail.
It wouldn't be the first low-pressure (under 200 psi) "vessel" that I've welded (I made some aluminum and steel air tanks for air shifters on drag race bikes, and some accumulators. Some people used PVC for race bike shifter tanks!), and I tested those at many times the working pressure using hydraulic fluid.

Facts are not on your side. I’m done here.

 

[Kyle_in_Tex]

I have probably the same exact rim on our deere. It does not leak around the mounting hoops. I just went through many "hoops" to fix a flat, sanding, grinding and painting the inside part of the rim. Turns out my tire's bead has a bad spot. I bought some bead sealer (wasted money). Then I finally fixed it with about 1/2 gallon of slime. It's been holding for about 3 weeks so far.

Good luck.

I've seen 24" rims on ebay for about $125-150 in silver.

 

[fried1765]

Facts are not on your side. I’m done here.

I know nothing about pyrolysis, but I am trying to figure this out.
Take the tire off the rim.
Clean up the damaged rim area, and weld repair same.
Repaint rim.
Are you suggesting that it is likely for pyrolysis to occur, sometime after the tire has been mounted back on the repaired rim?

 

[pmsmechanic]

So I just looked up the word pyrolysis to try to figure out what RickB is talking about. If I understand things correctly then pyrolysis is the word used to describe the chemical reaction that takes place when you weld on a rim with rubber covering the area being welded. The problem being that the absence of oxygen causes an undesirable chemical reaction that can be quite dangerous.

Furthermore I find the use of the word pyrolysis which so few people know the meaning of to be stupid in this case. Yes I'm being blunt! The reaction can be so dangerous that in my opinion it's very poor judgement to use that word! All you need to tell people is that if you weld on a rim with the tire still mounted that dangerous pressures can build up and the rim/tire can explode.

Now RickB if you go back to post #1 and reread the whole thread you should be able to see where your thought process got derailed. In my reading of the thread I never once came to the conclusion that fried1765 intended to weld on the rim with the tire mounted.

 

[CincyFlyer]

So I just looked up the word pyrolysis to try to figure out what RickB is talking about. If I understand things correctly then pyrolysis is the word used to describe the chemical reaction that takes place when you weld on a rim with rubber covering the area being welded. The problem being that the absence of oxygen causes an undesirable chemical reaction that can be quite dangerous.

Furthermore I find the use of the word pyrolysis which so few people know the meaning of to be stupid in this case. Yes I'm being blunt! The reaction can be so dangerous that in my opinion it's very poor judgement to use that word! All you need to tell people is that if you weld on a rim with the tire still mounted that dangerous pressures can build up and the rim/tire can explode.

Now RickB if you go back to post #1 and reread the whole thread you should be able to see where your thought process got derailed. In my reading of the thread I never once came to the conclusion that fried1765 intended to weld on the rim with the tire mounted.

Yep, someone doesn't understand what is going on, or what is intended. As long as the tire is not exposed to excessive heat, you are good to go. If the tire is out of harms way (whether broken from the bead and kept from the hot metal—I have several welding blankets—or removed completely) pyrolysis cannot occur. Heck, my wheels have yards of welding on them already, and I'd have no issues with this.

 

[RickB]

I know nothing about pyrolysis, but I am trying to figure this out.
Take the tire off the rim.
Clean up the damaged rim area, and weld repair same.
Repaint rim.
Are you suggesting that it is likely for pyrolysis to occur, sometime after the tire has been mounted back on the repaired rim?

No, I am not.

 

[Mad Mac]

Here is a final note. I contacted Titan Wheel directly. Here is the email I sent:

To: wheels.customerservice@titan-intl.com

Our Mahindra 5555 is about two years old with 400 hours on it. A front tire began leaking down overnight. Our local ranch supply store tire man found it blowing bubbles at two of the wheel rim loops. When he put a tube in it, a barely perceptible crack could be seen inside the rim at the nugget formed by the spot welding. The wheel was not abused.

Is this likely to happen on our other rims? Should the rim be replaced? Is there a chance the wheel would come apart while being driven? What is the correct way to fix these cracks or to prevent them from occurring? How long is the warranty on your wheels?

Here is the prompt reply I received. Names and contact info have been redacted.

Sent: Tuesday, January 02, 2018 9:05 AM
Subject: RE: Spot Weld Nuggets Leaking Air

Good Morning,
I'm afraid that your wheel is out of warranty [one year], you are under on the hours but around double on the time frame. This is an issue that we have seen a few times in the past on front wheels. You will probably be ok running tubes in the tires, especially with the low hours of use.
Thanks,

Technical Services Technician
Titan Wheel Corp of IL


It is curious that the technician suggested no other solution
yet seemed to hedge on the long-term service prospects for the rim.

 

[mcfarmall]

Facts are not on your side. I’m done here.

I think the problem (pyrolysis) occurs when welding/heating a wheel rim while the tire is still mounted on the wheel/rim. At least that's how I understood the process from the Bridgestone safety video. If the tire is completely dismounted from the wheel/rim prior to applying heat, then there would be no more danger present other than what is common to ordinary hot work situations.

CincyFlyer stated that "I'd get the tire out of harm's way," which in my thinking would be dismounting it from the rim. If you laid a piece of steel across an unmounted tire on the floor and welded on the steel, what would happen? Would pyrolysis occur in the tire material?

These questions warrant further research.

 

[erkme73]

I'm glad I stumbled upon this thread. This pyrolysis is a very intriguing phenomenon. The Bridgestone narrator does describe an incident where the catastrophic event happend even though the tire bead had been broken. IIRC, two guys were working on it, one was killed, the other seriously injured - and he was able to relay what happened.

Apparently the off-gassing from the rubber once the reaction starts, happens so quickly, that if the tire is still on the rim, the rapid increase in pressure can pop the tire back onto the rim and still rupture. Crazy stuff.

I recalling watching videos (after hearing stories) showing guys spraying ether and other flammable liquids into a mounted but unseated tire, and lighting it - where the explosion pops the tire on fully. I wonder if that could trigger the same type of reaction.