Bumper Air Tanks Yea or Nay?

[kgblazerfive]

I say nay also. Other then why when you can find or get small air tanks from just about any auto store for $20 how much time does it take to weld a bumper then what if it doesn't work. I got one from a Semi paid $0 for it and it comes with mounting brackets and fiting holes.

 

[SUPER'BURB]

I did this on my cherokee and love it.

Just remember to put a drain plug on the bottom edge towards the side so you can tilt it and let it drip.

 

[MarcS]

I have also had ignorant people think it is going to explode ; at most it could burst a weld and drain out.

It's not ignorant, It's illegal.

Have you seen any type of container, carrying any compressed gas, in any state that does NOT have a DOT stamp on it ???



{quote=gmcman7202]think about it, if the tank is pressureized, it will be harder to dent and damage[/quote]

I will not be harder to dent. Gasses compress.



Also, Power tanks, fire extinguishers, air tanks on semi's etc....All have to be mounted with DOT approved brackets.

Maybe our CK5 patrol officers/Troopers can shed more light on the subject and laws from different states.

 

[NoReGrEtS]

It's not ignorant, It's illegal.


Who has to know its an air tank looks like a bumper to me
and how many people dive in unsafe or riged up jacked to the sky no mud flap haven k5s does not stop them
I say make the air tank bumper unless your a wuss

 

[CyberSniper]

I vote No.

Unless you are well versed in ASTM Pressure Vessel Design & Welding practices I wouldn't do it.

Ever think that there is a reason that you air compressor's tank has rounded ends? Are you planning on making the bumper the same way? Flat ends put huge stresses on the welds holding them on. I can go on and on and on, but I'll stop here.

Just b/c it works doesn't mean it's safe.

Apparently you aren't well versed in ASTM Pressure Vessel Design & Welding practices either.

Most people build their bumpers out of 1/8" or thicker steel. Most air tanks are 18 gauge 1040... at best. A small diameter thick tube can have "square" ends. A large diameter thin tube needs something near a parabolic shape whether it be pointing inwards or outwards. It's mostly due to work hardening from the ends moving under pressure that causes cracks to form.

An air tank made out of most annealed metals isn't going to explode at 250psi... it's going to rupture. It's not like PVC where it'll explode.

I say nay also. Other then why when you can find or get small air tanks from just about any auto store for $20 how much time does it take to weld a bumper then what if it doesn't work. I got one from a Semi paid $0 for it and it comes with mounting brackets and fiting holes.

Not all vehicles have a lot of real estate to mount a tank. My wheeling rig only has enough room for a ~3 gallon tank.

It's not ignorant, It's illegal.

Have you seen any type of container, carrying any compressed gas, in any state that does NOT have a DOT stamp on it ???

Hold the bananaphone, what about your air conditioning system? I can't think of any DOT-placard required item that is pressurized under 500psi that isn't required due to being a hazardous material. If you can think of one, let me know.

Oh yeah, they better quit selling aerosol cans also at the stores... only safe to walk with them because they be so dangerous mon. We'll forget that most of them use propane for the propellant. That be some safe **** mon.

think about it, if the tank is pressureized, it will be harder to dent and damage

I will not be harder to dent. Gasses compress.

Alright, that just doesn't make sense. Go shake up a can of Coca-cola and try squishing it. Now open it and try squishing it. Oh, and enjoy the gooey keyboard.

Also, Power tanks, fire extinguishers, air tanks on semi's etc....All have to be mounted with DOT approved brackets.

Maybe our CK5 patrol officers/Troopers can shed more light on the subject and laws from different states.

Power tanks are CO2 tanks... at what pressure again? Commercial fire extinguishers are at what pressure again? My fire extinguisher in my truck is a lower pressure plastic one and it falls out of its bracket if you look at it wrong... DOT inspector must've been on a "b" double "e" double "r" "u" "n". I wonder if my 1700psi nitrous bottle has a DOT-approved bracket on it. Last I checked, an air tank on a semi is a critical part of the braking system. I wonder if the brake linings have to be DOT approved on a semi. I bet they aren't a critical part.



If one of you guys wants to send me $30 I'll go buy an air tank from Wally-world, fill it up with 150lbs of air, and go smack it with a claw hammer on video for you.

 

[MarcS]

Hold the bananaphone, what about your air conditioning system? I can't think of any DOT-placard required item that is pressurized under 500psi that isn't required due to being a hazardous material. If you can think of one, let me know.

Oh yeah, they better quit selling aerosol cans also at the stores... only safe to walk with them because they be so dangerous mon. We'll forget that most of them use propane for the propellant. That be some safe **** mon.



Alright, that just doesn't make sense. Go shake up a can of Coca-cola and try squishing it. Now open it and try squishing it. Oh, and enjoy the gooey keyboard.


Power tanks are CO2 tanks... at what pressure again? Commercial fire extinguishers are at what pressure again? My fire extinguisher in my truck is a lower pressure plastic one and it falls out of its bracket if you look at it wrong... DOT inspector must've been on a "b" double "e" double "r" "u" "n". I wonder if my 1700psi nitrous bottle has a DOT-approved bracket on it. Last I checked, an air tank on a semi is a critical part of the braking system. I wonder if the brake linings have to be DOT approved on a semi. I bet they aren't a critical part.



If one of you guys wants to send me $30 I'll go buy an air tank from Wally-world, fill it up with 150lbs of air, and go smack it with a claw hammer on video for you.

I'm not talking about the DOT placard requirements, I'm talking about pressurized GAS containers, not liquidfied compressed gasses, HAZMAT or not.

When I get a change to look around under my hood, I'll see if there is any markings on the A/C system.

Aerosol cans, I don't know . They do blow up good.

I know there is some room for the carbonated gas to expand, but I don't think it's relavent here. Coca-cola is a liquid. Liquids do not compress, I'm sure I can get the can to squish a bit from that little space, but I'm also sure it's going to blow about the same time or very shortly afterward. The can can't hold the liquid in.

Every fire extinguisher I have bought (Cheap plastic or metal cylinders) said in the paperwork that comes with it that it must be mounted in a DOT approved bracket to be mounted in a vehicle or boat. They are made of metal, not the cheap plastic ones that come with most of them.
The good ones (metal) ALL have hydrostatic test dates on them and all kinds of stamppings on them, DOT, serial numbers, lot numbers etc....This goes for all metal/composite cylinders made.
The air tank I bought at Wally World does have DOT stampings on it.
Why do you think all propane cylinders all have hydrostatic dates on them now. They won't fill the old ones anymore.

I bet to legally mount your Nitrous, you need a DOT approved bracket. Call up NOS and ask.
Go look at an air tank on a big rig, I bet it has DOT numbers and hydrostatic dates on it also. And the brackets are DOT approved.

Ok, I gotta go use my bannaphone now and call the FD, my deodorant blew up my bathroom. Then I have to get a new keyboard. This one has cola all in it.



O & A Party Rock

 

[CyberSniper]

I'm not talking about the DOT placard requirements, I'm talking about pressurized GAS containers, not liquidfied compressed gasses, HAZMAT or not.

To me, a liquified compressed gas is the most dangerous as it has a large amount of vapor available. Depending on ambient temperature, many compressed gasses are liquid at around 1500psi.

The low pressures most air tanks sit at are negligible when it comes to danger. Even a softdrink can which happens to be a hardened aluminum only splits when it ruptures. I'm willing to bet money that the only reason the air tanks on a semi have to have an approved bracket is because it's a critical part of the braking system.

When I get a change to look around under my hood, I'll see if there is any markings on the A/C system.

Probably not, and it sees 300 psi on the high pressure side.

Aerosol cans, I don't know . They do blow up good.

That's because the propellant is flammable. Most of the time it's either propane or butane or both... just there is no odorant in it. You can usually set the spray out of a paint can on fire and it's not because the paint is combustible.

I know there is some room for the carbonated gas to expand, but I don't think it's relavent here. Coca-cola is a liquid. Liquids do not compress, I'm sure I can get the can to squish a bit from that little space, but I'm also sure it's going to blow about the same time or very shortly afterward. The can can't hold the liquid in.

A pop can has roughly 40lbs of pressure in it (relative to atmospheric pressure) at room temperature due to the carbon dioxide coming out of solution. It's a lot harder to compress an item with 40lbs of pressure pushing out than no pressure pushing out. Think of a pop can like a tire. If you think pressurizing the contents has no bearing on it then go let all the air out of your tires and tell us the result.

Every fire extinguisher I have bought (Cheap plastic or metal cylinders) said in the paperwork that comes with it that it must be mounted in a DOT approved bracket to be mounted in a vehicle or boat. They are made of metal, not the cheap plastic ones that come with most of them.
The good ones (metal) ALL have hydrostatic test dates on them and all kinds of stamppings on them, DOT, serial numbers, lot numbers etc....This goes for all metal/composite cylinders made.
The air tank I bought at Wally World does have DOT stampings on it.
Why do you think all propane cylinders all have hydrostatic dates on them now. They won't fill the old ones anymore.

I don't have any of my destructions left from my fire extinguishers but I can tell you that none of my disposable ones have a mounting bracket that is worth a ****. They don't play by the same rules as commercial or serviceable fire extinguishers.

Propane cylinders have been tested since the early 80s and have required that they be checked every 10 years. They were never supposed to be filled if they were expired. The only reason people pay attention to it now is because you can be fined... and after a bunch of DMFs overfilling cylinders and people unscrewing the regulator without turning off the valve they all now have to have new valves on them before filling.

I bet to legally mount your Nitrous, you need a DOT approved bracket. Call up NOS and ask.

I doubt it. The bottle has to be DOT approved and it can't be in the passenger compartment. Someday soon you won't be able to have anything in the passenger compartment. I'm really surprised powertank and company let people put them in the passenger compartment. One paintball gun loser overfills the tank, the blowoff gets released as you're driving down the road because of the heat/vibration, and in 3 seconds it's 30° below and you're dying from hypoxia and burnt (frozen) lungs.

Go look at an air tank on a big rig, I bet it has DOT numbers and hydrostatic dates on it also. And the brackets are DOT approved.

What happens when that air tank leaks? No brakes worky work? What if the tank falls off?


You have a better chance of dying from getting into the bathtub than you do of a 150psi chunk of soft metal exploding and killing somebody.

 

[Leper]

 

[boz42]

If one of you guys wants to send me $30 I'll go buy an air tank from Wally-world, fill it up with 150lbs of air, and go smack it with a claw hammer on video for you.

that is the best one i have heard in a while

 

[wildmouse216]

I've seen guys use their roll bars as air tanks too. I have worked in the construction trades a long time and I have seen air tanks bust and they always just split and the air goes out. No explosions. And yes gas compresses, that is why it is 150 psi. But fill a tire up with 150 psi and see if you can push it in. Compressed gas pushes out thus making a metal container harder to dent. As far as if it is legal try it and see. You can always let the air out if a cop stops you. Too many whiners about what is legal. Fear should never replace reason and theory should always be tested in a real world environment. Deer kill more people every year than sharks do but who is really afraid of running over a deer. Car crashes kill lots more people each year than airplanes do but you don't think twice about hopping in the car to run downtown. But everybody is a nervous flyer. By the way I have hit a compressed air container with a claw hammer. Just lets the air out.

 

[CyberSniper]

Compressed gas pushes out thus making a metal container harder to dent.

Blasphemy!

By the way I have hit a compressed air container with a claw hammer. Just lets the air out.

More blasphemy!

 

[Can Can]

I think what this all boils down to is doing something "the right way". Making a homemade bumper and designing it to act as a pressure vessel does not fall under that description, unless you know what you're doing. In addition, I don't think CK5ers should be encouraging a guy to try something like this without a firm understanding of his abilities or knowledge.

Some of you guys obviously have a lack of respect for pressure and the results of it being accidentally released. I've worked on pressurized gas lines(30 - 550 PSI) EVERY DAY for the last 18 years and being around them for that long has made me realize that monkeying around with pressurized ANYTHING is dangerous. I've felt the results of a short 80 PSI release from a 2" valve on my arm, and I've watched a blind flange come apart when a 60 PSI run hasn't been bled down properly. It's amazing how much product can be compressed into 6 feet of 3" pipe, and it's equally amazing to see the results of it being released without the proper controls in place.

Sugar coat it if you want, or pretend that the risk of danger is not there. If properly constructed, the degree of risk associated with such a project can be substantially lowered. Unfortunately, not everybody out there is well-versed enough to "do it right". I'm sorry, but some things are better left to the pros......

 

[CyberSniper]

In addition, I don't think CK5ers should be encouraging a guy to try something like this without a firm understanding of his abilities or knowledge.

That never stopped anyone from telling a person to do an axle swap or a lift kit. Imagine if a spring pin sheared on the front axle.

Some of you guys obviously have a lack of respect for pressure and the results of it being accidentally released. I've worked on pressurized gas lines(30 - 550 PSI) EVERY DAY for the last 18 years and being around them for that long has made me realize that monkeying around with pressurized ANYTHING is dangerous. I've felt the results of a short 80 PSI release from a 2" valve on my arm, and I've watched a blind flange come apart when a 60 PSI run hasn't been bled down properly. It's amazing how much product can be compressed into 6 feet of 3" pipe, and it's equally amazing to see the results of it being released without the proper controls in place.

Air pressure, at say 150psi, isn't all that great. If you were to strategically place a blow dart in a tube over a rupture point then it'd be dangerous. A piece of schedule 40 black pipe, when ruptured, merely splits. Even the fittings that are crappy cast iron rarely fragment.

A piece of mild steel is not a piece of PVC (which will kill people when it ruptures at 150psi). 150psi isn't all that much in a chunk of mild steel.

150psi is only 15 atmospheres of pressure. There isn't all that much gas compressed into something at 150psi. Something at say 600psi is a lot more dangerous... not merely 4 times more dangerous.

I think what we've got here is a classic case of not seeing the forest through the trees. Instead of playing with hypotheticals, why not go and try it? 150psi in a chunk of mild steel is not anything to be afraid of. Well, if you happen to stick your ear next to the ruptured then that's something to be afraid of.

The most dangerous part about using a bumper as an air tank isn't the air tank. The dangerous part is the fact that you now turned the other car into the crumple zone.

Sugar coat it if you want, or pretend that the risk of danger is not there. If properly constructed, the degree of risk associated with such a project can be substantially lowered. Unfortunately, not everybody out there is well-versed enough to "do it right". I'm sorry, but some things are better left to the pros......

We're talking about 150psi in a say, 4 gallon tank, probably made out of 3/16" or thicker steel. There is no candy coating, just the laws of physics and a wee bit of common sense.

Honestly, if 150lbs in a chunk of tube is enough to scare people in the offroading community then they should probably stick to bicycles and paved railtrails.

 

[Can Can]

***Edited before I pressed "submit"*****

1.

That never stopped anyone from telling a person to do an axle swap or a lift kit. Imagine if a spring pin sheared on the front axle.

Apples and oranges.

2. You missed the entire point of my post. I'm not surprised, though......
BTW, some of know the theory, and some of us put it into practice and live around it everyday. I know which of the two describes me- which one are you?

 

[CyberSniper]

1. Apples and oranges.

Explain to me the apples and the oranges because I clearly do not see the two fruit getting confused. I clearly explained why it is not dangerous to make a bumper that is an air tank. If it takes great skill to make a "not dangerous" bumper that is an air tank then it must take even greater skill to properly install a lift kit.

2. You missed the entire point of my post. I'm not surprised, though......
BTW, some of know the theory, and some of us put it into practice and live around it everyday. I know which of the two describes me- which one are you?

I saw no point in your post other than "it is dangerous if you do not know..." To me, there was no point because there is a miniscule amount of danger. For someone to even attempt to make a bumper, let alone an air tank out of a bumper, they must have at least the basic understanding of physics (F=m*a and you can't push on a rope).

I've smacked items made out of mild steel that were under several hundred pounds of pressure and nothing spectacular happened. Even if you were able to hit a piece of mild steel so hard that the pressure inside of it were to increase exponentially before it broke where the impact was it still wouldn't shatter. The material properties are not there to be dangerous. It's not like a piece of glass, a piece of PVC, or anything of the nature.

Honestly, I'd like to know what I'm missing.

 

[MarcS]

Canmore summed it up a lot better than me.

I would not want to be some rescue worker at an accident, cutting someone out of a car when one of your crappy welds burst because you wanted to think your an engineer and or above the law.

I've also noticed most people that responded "Yea" are under 25 years old and still in that "Know it all" phase of life.

I'm done with the subject. I can afford to buy the properly approved containers and mounts.

 

[ntsqd]

Apparently you aren't well versed in ASTM Pressure Vessel Design & Welding practices either.

Most people build their bumpers out of 1/8" or thicker steel. Most air tanks are 18 gauge 1040... at best. A small diameter thick tube can have "square" ends. A large diameter thin tube needs something near a parabolic shape whether it be pointing inwards or outwards. It's mostly due to work hardening from the ends moving under pressure that causes cracks to form.

You are right, I can't qoute them verbatim. Can you?

Adding thickness to replace good design is exceptionally bad practice. At the risk of offending someone I'll call that the N-rigged method of building it. Has it occurred to anyone here that maybe those design practices, REGARDLESS of the metal thickness, came about b/c of bad experiences? Why the **** do you want to risk repeating them?

An air tank made out of most annealed metals isn't going to explode at 250psi... it's going to rupture. It's not like PVC where it'll explode.

You have obviously never set off a "veggie bomb." 6 times out of 10 it will do as you describe. The other 4 times one end goes flying. It IS effectively shrapnel. Those are not good odds.

Hold the bananaphone, what about your air conditioning system? I can't think of any DOT-placard required item that is pressurized under 500psi that isn't required due to being a hazardous material. If you can think of one, let me know.

Gee, don't suppose those systems are designed by ppl who know what they're doing?

Oh yeah, they better quit selling aerosol cans also at the stores... only safe to walk with them because they be so dangerous mon. We'll forget that most of them use propane for the propellant. That be some safe **** mon.

Butane. And they blow about the same as the veggies bombs do, which only have steam to power them.

Power tanks are CO2 tanks... at what pressure again?

How often do you plan to Hydro-Test your Bumper? Ever try to fill an out of date tank?

Fear should never replace reason and theory should always be tested in a real world environment.

Excellent quote, and the ASTM design guidelines are the result of many years of this.

With this post I'm done on the topic. Canmore summed it up for me.

 

[Dallin]

This has been very entertaining and a little educational too. Both sides have made some good arguments, but you're making this way to personal. I would like to add that I don't think this project is for everyone. This is the case with many modifications we make to our vehicles. I'm a certified welder, an engineer, and have many years of schooling, and practical experience. If I can convince myself that my design is safe I'm quite confident that I can build it. That doesn't mean I think everyone should build one.

Let's try to look at this logically, and less emotionally to determine if the risks involved with using a bumper for an air tank are unreasonably high. Let's also consider bumper design in the safety equation. Some of you have referred to ASTMs. Please list the ASTM number you think is applicable. I'll review the ASTM and post any part I think might be of interest to people on the board. If there are DOT regulations that apply to pressure vessels used in motor vehicles please post a link or give us a reference.

 

[79k20350]

i saw i posted a while ago about using the ac compressor instead of the york. you can make this work, you just need an inline oiler before the compressor and a seperator afterwards to make it work. very easy to do especially cause its already there

 

[bigjbear]

This has been very entertaining and a little educational too. Both sides have made some good arguments, but you're making this way to personal. I would like to add that I don't think this project is for everyone. This is the case with many modifications we make to our vehicles. I'm a certified welder, an engineer, and have many years of schooling, and practical experience. If I can convince myself that my design is safe I'm quite confident that I can build it. That doesn't mean I think everyone should build one.

Let's try to look at this logically, and less emotionally to determine if the risks involved with using a bumper for an air tank are unreasonably high. Let's also consider bumper design in the safety equation. Some of you have referred to ASTMs. Please list the ASTM number you think is applicable. I'll review the ASTM and post any part I think might be of interest to people on the board. If there are DOT regulations that apply to pressure vessels used in motor vehicles please post a link or give us a reference.

Now, now lets not do anything hasty, like looking up facts.