BH92 Welding at cylinders falling apart

[mcmxi]

"picky"?
I have never found any moisture in household electrical boxes, or main service entrance, but over the years many houses have been consumed by fire, determined to be caused by the aluminum/dissimilar metal corrosion issue.

I'm being picky ... that's what I meant.

Aluminum will oxidize in the presence of oxygen. Aluminum oxide is non-conductive and when it builds up it creates a resistance to the flow of electrons. This causes the connection to heat up and can result in a fire. All because you can't see any moisture in the electrical box it doesn't mean that moisture isn't present or hasn't been present.

Back to aluminum. If you've ever tried to weld aluminum you'll know that you have to clean the surface right before you start welding. A thin oxide layer will form instantly and continue to grow so you need to start welding when it's just a few microns thick. Aluminum oxide has a higher melting temperature than aluminum and as mentioned, is an insulator.

 

[Ackman]

Diagnosis: stainless fitting and soft steel welds are creating galvanic corrosion- can't believe Kubota wouldn't have thought of this. As I noted we live on an island surrounded by salt water and the air is laden with salt all year round. Humidity levels are usually quite high as well.
That said I went by a friend's Woods backhoe yesterday; Thirty years old, the cylinder welds are completely beautiful including the original paint- though faded, no corrosion is
present. The rest of his tractor is a different story....

 

[Henro]

"picky"?
I have never found any moisture in household electrical boxes, or main service entrance, but over the years many houses have been consumed by fire, determined to be caused by the aluminum/dissimilar metal corrosion issue.

I remember using a paste called something like "no ox" on aluminum wire used in place of copper wire. Perhaps the issue with aluminum wire is not the same thing, even though there are dissimilar metals involved?

Also, aluminum seems to be softer than copper. Maybe fires resulted from the aluminum compressing over time, and resulting in a high resistance connection, thereby producing heat that could start the fire?

I am pretty sure that a conductive path is needed for galvanic corrosion to occur...getting interested now...guess google will be my friend again...

Edit: I should learn to read all the posts before replying. Mcmxi already addressed this question...

 

[whitetiger]

can't believe Kubota wouldn't have thought of this.

News flash::::::::::::::::: Kubota did not manufacture that cylinder. It is designed, manufactured, and supplied to Kubota from an independent supplier.

 

[Mark_BX25D]

"picky"?
I have never found any moisture in household electrical boxes, or main service entrance,

It doesn't have to be visible to the naked eye, but it's there.