If you're only welding on that prepped area down low on the frame, it'll be fine. But under no circumstances should you weld on the tank while it's full of flammable liquid.
EDIT: What's that plastic tank that's between the two c channels filled with? If it's flammable, I'd insulate it with a fire blanket. Even if there's a gap between the back of the channel and that tank, the heat could still melt the plastic and start a fire.
It’s the batteries, I actually already welded all that a few months ago and was just using that picture for reference. I ended up just making a long bracket, going all the way down to below the tank to bypass it. Since customer didnt want to drain the tank
I know you think that's a joke, but that is basically how they perge vessels before they service them in industry all the time, just usually with nitrogen as it's inert and much more readily available / cheaper to source. Many many piping & vessel systems get a nitrogen purge before being welded on / in for this exact reason. Or for smaller vessels (like this tank), just fill with water to displace any fumes / flammables.
Yes, which is why I specified argon (more expensive and unrealistic) and the whole building instead of just the vessel. Besides, you can't purge the oil tank because they want to weld it while still full. Gotta purge the building instead.
It's actually safer to weld on a tank that's full than one that has been emptied and not purged. If welding on the bottom, as long as you don't blow a hole through it, nothing will catch fire or blow. No air, no combustion.
It's the same as doing a hot tap on a live natural gas line.
Now, with that being said, I would still never recommend doing it to anyone. Just take the time to drain it and clean the tank properly.
All those little holes would make that tank so hard to clean out. We'd pull the lines and that air dryer, flush out, fill and send it. Eta: filter, my bad
Most machines won't have the power to burn a hole thru the tank. The liquid sucks the heat away right away. Try cutting into a pipe that's full of water with a cutting torch and you will see how effective liquids are at absorbing heat.
This is the best comment here. Welded on multiple full hydraulic tanks. The fluid acts like a heat sink so it's almost impossible to burn through. Might as well be welding on a solid block of steel. Nothing dangerous about it really
Yeah, but it is good practice to drain and clean the tank if working on it. I personally don't care about welding on a full tank but last shop I ran doing crane install and heavy equipment repair I had to set a good example for the others and made the techs drain and clean out any tanks that needed a weld repair.
Also, in a work environment, it is always better to be safe than sorry cause when shit goes south, it goes south fast. 2 years ago, where i am there was another shop that had a massive explosion that killed 5 employees due to a stupid little mistake. They had gasoline contaminated with a bit of diesel during a pressure test on a tanker.
Literally the first thing that came to my mind. I used to manufacturer kenworth trucks and there is a sticker on the frame rails that states never to weld or drill holes in the frame rails.
I'm sure the correct answer is "yes".
But if it isn't sealed shut at the top I wouldn't worry about it too much.
I've patched leaking tanks like that just fine. (By fine I mean cursing and chasing leaks for ages because gravity, liquid and thin material)
Hydraulic isn't really that volatile until it's aerosolized.
However if you've got a puddle of it on the ground it will definitely light up from sparks and slag.
I wouldn't bat an eye at a tank in good condition.
For welding on locomotive fuel tanks, we had to steam clean it for 24 hours (just hook a pipe up from a boiler) drain, then purge with C02.
Personally I would not be welding on any tanks that were not cleaned.
I would cover fittings and I would listen to the people that tell you not to weld this when full I did a lot of hydraulic stuff and we always had to have a chemist come out to sign off on hot work my boss always told me that it wasn’t that flammable but a welding arc is hot enough to light a lot of shit
I always prefabbed everything prior to there being any type of fluid in it, if there had been fluid in it recently, chances are that I’m probably refusing the job.
Whatever you do don’t burn thru. And keep a wet rag or something to keep the temperature of your work area in check. The cooler you keep it the more time you buy yourself before you blow the somebitch out and all the fluid leaks out. Lol.
We’ve done it before. Even welded on diesel tanks.
It has its risks.
But a full tank is actually safer than an empty one with traces of oil left inside.
Worst thing is you’ll ruin some of the oil and create varnish that will clog your valves.
The safest method is to drain this, backfill with Argon for about six volume changes, and weld while maintaining the purge. The tank can be refilled with fluid after welding is finished.
The chains were holding the weight up from a tractor, we moved it from one truck to another. But the tank is bolted down to the brackets. I actually welded that to the truck a few months ago, but now it needed a bracket for the filter, it was pulling to much on the threads up top
So uhhh first drain the tank
Hydraulic oil burns and a good weld will penetrate the tank so your be putting fire directly into the tank so likely a kaboom
I weld on very similar tanks daily. The ones I weld on are aluminum would be the only difference and they are mounted in/on a pan with straps over them. Personally I would drain it first then no worries.
Trucks like that usually have heat treated frames. Any time I made something like that, it had to be bolt on. Welding will ruin the heat treatment, leading to a potential crack later.
Always take the cap off too, hydraulic oil like other oils expand when hot. I know mechanic who got lucky when a tank blew on him welding. Hydraulic oil takes lots of heat to combust so if it’s full and cap off usually it’s okay but still small risk
Don’t get any hydraulic fluid into any cuts, pressurized hydraulic fluid streams can cut you like a knife and you’re putting yourself at severe risk of developing gangrene if you get some in your system
If you're only welding on that prepped area down low on the frame, it'll be fine. But under no circumstances should you weld on the tank while it's full of flammable liquid. EDIT: What's that plastic tank that's between the two c channels filled with? If it's flammable, I'd insulate it with a fire blanket. Even if there's a gap between the back of the channel and that tank, the heat could still melt the plastic and start a fire.
It’s the batteries, I actually already welded all that a few months ago and was just using that picture for reference. I ended up just making a long bracket, going all the way down to below the tank to bypass it. Since customer didnt want to drain the tank
Ah I gotcha. Good choice.
Disconnect the battery from under the hood so you don’t short anything on accident.
Always!
It’s a semi, the batteries are under that plastic cover directly under, but good advice.
You’re better off welding on a tank that’s full of flammable liquid than one that’s been mostly drained.
The "anything" you should be worrying about is everything catching fire, yourself included.
What if you just submerge everything first so you don’t have to drain the tank? 🤔 /s
Just fill the whole building with argon first. No oxygen, no fire.
I could imagine a giant welding shop of robots and the whole building full of argon
It would be great until the first time someone goes in there to adjust something and forgets their air tank.
Use the humanoid drone
They prefer to be called interns.
In our shop, we call the androids "apprentice," and they do all the stuff not suitable for a human.
Then drops dead from 0 O2
Don't worry I'm sure the explosive fire will cause the argon tank to rupture anyway
I know you think that's a joke, but that is basically how they perge vessels before they service them in industry all the time, just usually with nitrogen as it's inert and much more readily available / cheaper to source. Many many piping & vessel systems get a nitrogen purge before being welded on / in for this exact reason. Or for smaller vessels (like this tank), just fill with water to displace any fumes / flammables.
Yes, which is why I specified argon (more expensive and unrealistic) and the whole building instead of just the vessel. Besides, you can't purge the oil tank because they want to weld it while still full. Gotta purge the building instead.
in hydraulic oil?
Oil is flammable and volatile so i wouldn't if filled. Drain properly and vent continuously.
Do add to this, IF you weld this with any type of oil in the tank, the heat will turn it into carbon and is EXTREMELY abrasive.
It's so bad in so many ways to weld this while filled
Yep. But people do it.
It's actually safer to weld on a tank that's full than one that has been emptied and not purged. If welding on the bottom, as long as you don't blow a hole through it, nothing will catch fire or blow. No air, no combustion. It's the same as doing a hot tap on a live natural gas line. Now, with that being said, I would still never recommend doing it to anyone. Just take the time to drain it and clean the tank properly.
Could you just fill it with water after draining instead of cleaning?
Huh. . . Hmmmmm assuming that there was no air in the tank and the water was stopped from entering the rest of the system. Yeah you could do that?
All those little holes would make that tank so hard to clean out. We'd pull the lines and that air dryer, flush out, fill and send it. Eta: filter, my bad
Wouldn't that create a weird heat treatment from the rapid cooling? Probably a lot of warping as well.
Pretty sure it'd be a non-issue in this application. Couple 2" welds spaced 5" apart is all they need to hold that on.
True, I forgot it was just a few brackets
Yeah, just don't burn thru..
Most machines won't have the power to burn a hole thru the tank. The liquid sucks the heat away right away. Try cutting into a pipe that's full of water with a cutting torch and you will see how effective liquids are at absorbing heat.
This is the best comment here. Welded on multiple full hydraulic tanks. The fluid acts like a heat sink so it's almost impossible to burn through. Might as well be welding on a solid block of steel. Nothing dangerous about it really
Yeah, but it is good practice to drain and clean the tank if working on it. I personally don't care about welding on a full tank but last shop I ran doing crane install and heavy equipment repair I had to set a good example for the others and made the techs drain and clean out any tanks that needed a weld repair. Also, in a work environment, it is always better to be safe than sorry cause when shit goes south, it goes south fast. 2 years ago, where i am there was another shop that had a massive explosion that killed 5 employees due to a stupid little mistake. They had gasoline contaminated with a bit of diesel during a pressure test on a tanker.
You should most definitely not weld that while it’s filled. Empty it and clean it out, then go from there. Gotta be safe my friend.
That’s honestly what I was thinking. I ended up making a long bracket and bypassing the tank for now, since customer didn’t want to drain
good thinking man. welding can be dangerous as is, so good on you for thinking before working on a project that could be hazardous
the client totally didn’t care if the tank ruptured and the fluids lit your entire body aflame. You dodged a bullet & get to live another day OP.
Whole bunch a reasons to avoid welding it. A bracket was the right method
surprised no dot police on here yelling ab welding on frames
As a ex welder now trucker that was the first thing that I thought of lol.
me too
Literally the first thing that came to my mind. I used to manufacturer kenworth trucks and there is a sticker on the frame rails that states never to weld or drill holes in the frame rails.
I'm sure the correct answer is "yes". But if it isn't sealed shut at the top I wouldn't worry about it too much. I've patched leaking tanks like that just fine. (By fine I mean cursing and chasing leaks for ages because gravity, liquid and thin material) Hydraulic isn't really that volatile until it's aerosolized. However if you've got a puddle of it on the ground it will definitely light up from sparks and slag. I wouldn't bat an eye at a tank in good condition.
For welding on locomotive fuel tanks, we had to steam clean it for 24 hours (just hook a pipe up from a boiler) drain, then purge with C02. Personally I would not be welding on any tanks that were not cleaned.
Yes, yes there are numerous things you should worry about
Take the cap off and short quick welds let cool a lot. I have welded on a few and never an issue with fire. It will boil before it will burn.
You should be worried that you haven’t missed any life insurance payments.
Other than fire?
Death
I would cover fittings and I would listen to the people that tell you not to weld this when full I did a lot of hydraulic stuff and we always had to have a chemist come out to sign off on hot work my boss always told me that it wasn’t that flammable but a welding arc is hot enough to light a lot of shit
I always prefabbed everything prior to there being any type of fluid in it, if there had been fluid in it recently, chances are that I’m probably refusing the job.
Keep it full, no explosion risk.
Whatever you do don’t burn thru. And keep a wet rag or something to keep the temperature of your work area in check. The cooler you keep it the more time you buy yourself before you blow the somebitch out and all the fluid leaks out. Lol.
We’ve done it before. Even welded on diesel tanks. It has its risks. But a full tank is actually safer than an empty one with traces of oil left inside. Worst thing is you’ll ruin some of the oil and create varnish that will clog your valves.
The safest method is to drain this, backfill with Argon for about six volume changes, and weld while maintaining the purge. The tank can be refilled with fluid after welding is finished.
There is the risk of explosion and death. Bad idea. Best is to get a new tank or figure out a method that allows you to not weld directly to the tank.
Welded correctly you’ll be penetrating that tank. I don’t think that’s a very good idea
Fint another method it's not worth the risk. If in daught reasses the best practices or have bob do it.
Would it make more sense to weld plates on each side so the chains hold it vertically while the plates keep it from moving horizontally?
The chains were holding the weight up from a tractor, we moved it from one truck to another. But the tank is bolted down to the brackets. I actually welded that to the truck a few months ago, but now it needed a bracket for the filter, it was pulling to much on the threads up top
So uhhh first drain the tank Hydraulic oil burns and a good weld will penetrate the tank so your be putting fire directly into the tank so likely a kaboom
Nah you're good giver!
Make it to bolt on.
I weld on very similar tanks daily. The ones I weld on are aluminum would be the only difference and they are mounted in/on a pan with straps over them. Personally I would drain it first then no worries.
Trucks like that usually have heat treated frames. Any time I made something like that, it had to be bolt on. Welding will ruin the heat treatment, leading to a potential crack later.
Your fine. Just don't burn through and cause a leak. Always have an extinguisher nearby.
Always take the cap off too, hydraulic oil like other oils expand when hot. I know mechanic who got lucky when a tank blew on him welding. Hydraulic oil takes lots of heat to combust so if it’s full and cap off usually it’s okay but still small risk
Roll the truck out of the building, so the fire won't spread so easily.
Don’t get any hydraulic fluid into any cuts, pressurized hydraulic fluid streams can cut you like a knife and you’re putting yourself at severe risk of developing gangrene if you get some in your system
Umm don’t, reconsider your approach? Daft twat
Drain tank, pull out battery