Air compressor tank

[Bmxin^Bjorn]

ok .. heres the deal . my buddy wants to mount an air tank on top of his jeep so he can fill his tires and stuff, he can't find a long skinny tank tho. Counld i take a peice of pipe and tig some plates on the end? would this hold 150PSI? i also need to weld on fittings. He's afraid im not going to get a consistant weld tho. i was planning to do a fillet all the way around and roll the pipe as i weld accross the floor.

[SkidSteerSteve]

Ok, brutally honest time.....If you aren't pressure vessel certified, then don't even touch a pressure vessel. Also, if you do go through with it, put caps, not plates on the end. If I were your buddy, I'd just go lease me a Ni cylinder and get a regulator and air hose. Then you can fab him up a nice mounting bracket and stuff for it. A 2000psi Ni tank will air up a lot of tires. SSS

[aametalmaster]

I got some nice long skinny tanks from the boneyard off of semi trucks, they use them for the air brakes....Bob

[Rufridr069]

I'd just go lease me a Ni cylinder and get a regulator and air hose.

What about a SCUBA Tank? We use one for that. We don't fill it to the 3000 lbs. We come off the low pressure side of the valve and it works great. You can find older steel ones real cheap on eBay.

[stick man]

air tank

It can be done with flat plate but you need to cut hole in center of caps and run a rod all the way across, and space the caps like you were making a test weld that was going to be x-rayed so you can push it through for 100% penatration. But bye the time you do this it's probaly easyer to buy.

[FusionKing]

I've seen a lot of "air bumpers" made over the years and thot... "man I wouldn't want to get hit with that!!"
Sorta a cannon ready to blow sideways!

[jfsmith]

Why not buy one of the air tanks your carry with you. They are like $30 for a 5 gallon one and $50 for an 11 gallon one.


Jerry

[JonnyTIG]

Air bumpers are an easy way to make an air tank for a vehicle. Most novice welders can put one together and not have to worry about any problems. 200psi will not explode a vessel like 2000 psi will, and a bumper/vessel made with sch 40 4" pipe with 1/4" end caps will do just fine. If the tank springs a leak, in a collision or otherwise, it will be nothing more than the same as if your air tool coupler pops out of the air hose while you are using it. Psssss goes the air. No ripping or flying metal. Don't build the tank, whatever type it is, out of too thin a material. mild steel, as in A36 or 44W has a 40,000 psi minimum tensil strength. Do the math, and you will be surprised at what pressures can be held in a given container. As for the welding, good fusion is the key. Grind the root weld stop-starts to ensure full fusion and clean the weldment between each pass. This is especially inportant if you are using GMAW due to the cold starts that are characteristic to this type of welding.

Hope this info helps you out.

[Amos F.]

I have driven and fixed semi trucks sine before I was legally old enough to drive them. No offense but buy a new tank if you are going to use one of this style. The old (in the 70's ) ones if looked after are good and strong, the newer ones are thinner and don't seem to last as long. They are not very much to buy (depending on the size you are after about $40 Can dollars) and they come with different mounting brackets welded to the tank. A truck parts supply place will have a book with all the tanks pictures(drawings) in it. Look at it and measure up your vehicle and you will likely find one you would think that someone had made specifically for your jeep.
Amos F

[Bmxin^Bjorn]

kay .. guys i did it and it worked . i used sch40 pipe with a 5'' id and ressesed the caps in the pipe and it works fine i've got it up to 200psi and no problems . oh and hey skid steer steve .. how do u become a pressure vessel welder if you don't try it. .. no offence or anything.

[dwain]

Easier answer to that offroad dilemma

I drive a small 4WD into Nevada's outback with a box full of coyote catch dogs, and so I've ruined tires in some desolate places. I carry two spares 'cause pumping up a ripped or cactus poked tire doesn't get one very far, and yet i know pumping up a tire could be the most convenient thing to do at a given time for the option of later changing the tire,...but I wouldn't carry the extra weight of a tank. I carry a small 12v pump. A spark plug hose is another option.

[Sparky C]

Once had a PVC 6'" end cap blow off while pressure testing at 70 p.s.i., it was very loud and painfull as I recal. that was plastic, yor talking steel at 120 p.s.i. ...... might want to consider the 30 doller one at pep boys, or the used truck air tank.

[SkidSteerSteve]

oh and hey skid steer steve .. how do u become a pressure vessel welder if you don't try it. .. no offence or anything.

non taken, but compressed gases is one of those areas that can get you into a lot of trouble real quick. Just like electricity, it usually doesn't say excuse me. There's a reason air and hydralics are used on so much industrial equipment...it packs a big punch in a small package. Of course, I'm a business owner and have to deal with long term liability of projects so I'm very quick to lean toward the coservative side of issues. Also, there can be manufacture liabilities to items that can come back to haunt you years from now. Just something to keep in mind.

Glad it worked. Keep on tinkering, but always keep safety, whether in the shop on in the design a primary goal. SSS

[jfsmith]

I vote for Dwain's solution, easy and simple. practical.

Jerry

[arc]

where im from if u weld a vessel and u arent b cert. you can lose your ticket and if some one gets hurt or killed ur looking at jail time. so dont even think about welding pressure vessels if u arent certified to do so. its just plain responsibility on your part to hold up to the codes and standards of your area. if you want to test for your b phone your local boiler branch and schedule a test its the smart way to do things dont just start welding on vessels unless u are certified but hey is your a** dont mean to say u cant weld or any thing just stating what the laws are up here no offense.