Welding onto hydraulic tank. Keep it full?

[cityevader]

I'm well aware of the extreme heat generated from welding, and the risk of potential fire or worse if fluid in tank ignites while welding vertical strip cooling fins onto it. My logic says it would be better to keep tank full (and not welding continuously to allow cool down) because if I drain it, the film/residue inside would be vastly more volatile (think empty airplane fuel tank explosion).

Perhaps between the fluid (MerconV btw) sucking away heat measurably and the 1/4" thick tankwall, it would sort of buffer the pinpoint heat so the inside would not get so intensely hot.

Anything else to consider?

 

[cityevader]

Oh yeah, the tank would have 8 gallons in it, so plenty of "cooling oil volume".

 

[husky455rancher]

mmmmmm touchy subject here i would think. ive been known to try stuff alot wouldnt lol. i would think you would be ok if you did small sections at a time and make sure no sparks get near the cap area. ill prolly try the same thing later on.

 

[046]

think explosion!!!

clean out with soap and water, then fill it up with an inert gas like nitrogen.

best of all take it to a pro... not worth the risk..

 

[gink595]

Go for it, I've welded on hyd. tanks, lines etc.. on broken ditchen machines while they were full. I wouldn't go full bore into it unless the tank was thicker metal and the worries of blow through were none. Crank er up assuming it is a mig welder and just 1" tack weld, go like hell and stop. Start in a different spot, repeat until it is welded fully, if you feel it is getting to hot have a wet rag near and quinch it until it is cooler. Just don't stay in one area to long, but I think the key is to have the welder a little hotter than normal so you can get good penetration at a fast rate rather than having it colder and having to slow to weld. Have fun!

 

[KsWoodsMan]

It is the vapors that are expolsive. Liquid fuel doesnt burn.
Keep the tank full, work quickly and don't blowthroughs.

Never work alone when welding like this. Have a standby watching out for anything unexpected. If it makes you feel better have your safetyperson hold a fire extinguisher.


Heh !
If you are daring have them ready with a garden hose while you work.
(That's a joke son ! - Foghorn Leghorn)

 

[redprospector]

If you weld it full of oil it will scorch the oil. Some of that scorched oil will stick to the wall of the tank, slowly coming loose over a period of time causing a short life for your filter. If you change your filter religously it probably won't be a big problem.
I generally empty the tank and fill it with water. That way I save the oil, and can just change the filter on my regular intervals.

Andy

 

[Coldfront]

If you are just trying to tack on a couple of brackets or something I think it would be ok to leave the tank full of oil, But if it is going to be a lot of welding, I would also drain it and refill with water like was suggested. Never weld on a empty tank that had a petroleum product in it. There was a welder here in town that died from cutting the top off of a 55 gal drum, it exploded.

 

[Patrick62]

Weld away!

Go for it. Make sure that it is full! Short 1" passes will be fine.

Never try welding on a "empty". I burned off some hair one day that way.

-Pat

 

[smoothED]

Are you fixing a leak or welding a bracket on? A little trick to fix a leak is stick a toothpick in the hole first,paint and leaking oil will catch on fire. Disconnect your battery if you have one. Fire blankets or scrap tin will protect rubber or other parts from splatter. If your not sure about what your doing go the safe route and take the tank off and fill it with water and weld,or bring it to a shop.

 

[woodchop]

I'm well aware of the extreme heat generated from welding, and the risk of potential fire or worse if fluid in tank ignites while welding vertical strip cooling fins onto it. My logic says it would be better to keep tank full (and not welding continuously to allow cool down) because if I drain it, the film/residue inside would be vastly more volatile (think empty airplane fuel tank explosion).

Perhaps between the fluid (MerconV btw) sucking away heat measurably and the 1/4" thick tankwall, it would sort of buffer the pinpoint heat so the inside would not get so intensely hot.

Anything else to consider?

What is generating the heat? worn valve?
Add a transmission cooler?

 

[smoothED]

[/COLOR]

What is generating the heat? worn valve?
Add a transmission cooler?

uuummmm.........welding

 

[cityevader]

The plan is to weld some vertical strips for a heatsink. Approx a foot in length, sticking out about 2 inches. Likely use 1/4" stock, perhaps a 12-15 fins welded on over quite a few days to allow full cooling between passes. Maybe a inch on one, then an inch on the opposite end of tank, then an inch in the middle, then cool.

As to what is causing the heat, i don't know. My prior thread of "return line psi" got some useful info, but I haven't had opportunity to measure ram speed loaded/unloaded so see if pump is bypassing or not. There are several 90* elbow connections. The engine seems like it slows a very tiny bit on the return stroke, but there's no tach to check with. Also nobody could give me any temp readings of their "normal temp" splitters. After 45 minutes the ram housing is nearly 130*F. Too hot to touch.

 

[KsWoodsMan]

The plan is to weld some vertical strips for a heatsink. Approx a foot in length, sticking out about 2 inches. Likely use 1/4" stock, perhaps a 12-15 fins welded on over quite a few days to allow full cooling between passes. Maybe a inch on one, then an inch on the opposite end of tank, then an inch in the middle, then cool.

As to what is causing the heat, i don't know. My prior thread of "return line psi" got some useful info, but I haven't had opportunity to measure ram speed loaded/unloaded so see if pump is bypassing or not. There are several 90* elbow connections. The engine seems like it slows a very tiny bit on the return stroke, but there's no tach to check with. Also nobody could give me any temp readings of their "normal temp" splitters. After 45 minutes the ram housing is nearly 130*F. Too hot to touch.

Those elbows all add up against you, Cure the cause and you dont have to treat the symptoms.

Why 1/4" stock? sure there is more mass there to heat but total heat transfer to weight would be better with 20 ga sheet metal. It would take less heat to put these on your 11 gauge tank. And they have the same surface area as thicker stuff without the cost.

Unless it is free and you dont mind using as much wire or stick to attatch it.

 

[husky455rancher]

i agree no need to use 1/4" stock. im going to make a series or heat sinks for mine here and there over the next couple weeks. ill use what i can get for steel but i wouldnt go any thicker than 1/8, preferably thinner if i can get it.

 

[Rookie1]

When I was 17 I went to wok part time in a landfill cleaning shop. I was scared sh**less watching the welder welding some brackets onto a fuel tank on a compactor.He thought it was funny that I was ready to run. Any way after that Ive never been afraid of welding on a tank like that.

 

[cityevader]

For 1/4". I was mostly thinking of strength. Many a heavy log has fallen in that area. But in retrospect, something along 1/8" (what's that, maybe 10 gauge?) would be fine since the load of a falling log would be lengthwise so to speak.

At this point, I'm thinking of running until a problem pops up, which is TOTALLY against my normal thought process of a Ford Lincoln Mercury tech who has seen it all in regards to car problems.

Maybe I should just but a friggin stopwatch to measure extend/retract times loaded vs. not loaded to calculate loss in the pump...I dunno. Maybe I just won't lean against any of the equipment anymore.

 

[kevin j]

If you have a small tank and spend some time on relief valve stalled into the log, 130F would be quite normal and no cause for worry. In that case the relief valve area may be 10-25F hotter than the rest of th system. I would run it.

But, were you the poster that had 130 tank, and maybe 175F at pump housing? Then the root issue is pump leakage and creating excess heat.

I would focus on finding the source of excess heat, not just on getting rid of it. If it is worn pump, the life span is not too much longer, it will only get worse.


k

 

[Patrick62]

It ain't that bad

130 is a touch on the high side. Think about this, what temp does a auto tranny running the same fluid operate at?? opcorn:

Next time I plan on splitting for a period of time I will check the temp. My machine levels off at probably 110 or so on a warm day.

-Pat

 

[cityevader]

130 is a touch on the high side. Think about this, what temp does a auto tranny running the same fluid operate at?? opcorn:

Next time I plan on splitting for a period of time I will check the temp. My machine levels off at probably 110 or so on a warm day.

-Pat

Actually, a late model Ford pickup has a cooler outlet that doesn't even open until 180*F is reached.... but some hydraulic site I read 140*F is max operating temp.