Welding Discussion Forums

Home » Resources » Communities » Welding Discussion Forums

Thread: Air Compressor takes a nap

1. Air Compressor takes a nap

My air compressor as decided to lay down on the job and I have a small aluminum job coming up this weekend so I'll be needing the plasma. I've searched and read but I still can't find a answer. I'll be hooking up a cylinder of compressed air. Lws pointed me toward med air. Its cheap and readily available. My question is how long would I expect this cylinder to last? Its a 335 cubic ft. Is it feasible or do I need to go ahead and bite the bullet and repair the compressor? \$\$\$\$

2. Originally Posted by sledsports
My air compressor as decided to lay down on the job and I have a small aluminum job coming up this weekend so I'll be needing the plasma. I've searched and read but I still can't find a answer. I'll be hooking up a cylinder of compressed air. Lws pointed me toward med air. Its cheap and readily available. My question is how long would I expect this cylinder to last? Its a 335 cubic ft. Is it feasible or do I need to go ahead and bite the bullet and repair the compressor? \$\$\$\$
335 cf @ what PSI..??

your plasma consumes how many CFM @ 60?? PSI..?? (60 is a guess... give us your real number)

then we will have to find the calc to figure the conversion..

how much cutting do you need to do??

What is the matter with your compressor??

3. Senior Member
Join Date
Mar 2011
Location
Posts
262
too many variables are missing to think of something...

what makes you think your compressor will be \$\$\$ ?

the air cylinder is a what pressure ? 2200, 2500 if it's the case it should last about the same time an oxy bottle, what is your post flow time on your plasma, pressure required for your alu. thickness...ahhh so many questions.

a guy stuck in the fields would think of stealing air from a large truck tire...

darn...hn80 beat me to the finish line lol

4. OK, you guys got me. I have no idea what PSI is in a Med air cylinder because I've never messed with one. My plasma says 6.7scfm @ 90psig. I'm cutting some 6"x 5/8" flat stock. Be about 16 square cuts total. I know the compressor is gonna cost \$\$\$\$ cause its a Quincy.

5. Originally Posted by snowbird
too many variables are missing to think of something...

what makes you think your compressor will be \$\$\$ ?

the air cylinder is a what pressure ? 2200, 2500 if it's the case it should last about the same time an oxy bottle, what is your post flow time on your plasma, pressure required for your alu. thickness...ahhh so many questions.

a guy stuck in the fields would think of stealing air from a large truck tire...

darn...hn80 beat me to the finish line lol
snowbird
.... heck no... dive right in...

we have to know consumption @ pressure

and understand exactly how many cubic feet of air we have in the tank at the pressure that the plasma cutter needs..

AND... Sledsports.... do you have a regulator that will make the pressure your plasma cutter wants..??

6. Originally Posted by H80N
335 cf @ what PSI..??

your plasma consumes how many CFM @ 60?? PSI..?? (60 is a guess... give us your real number)

then we will have to find the calc to figure the conversion..

how much cutting do you need to do??

What is the matter with your compressor??
Its a 3phase running off of a rotary phase converter or (add a phase) as some like to say. It burnt a leg up on my motor starter so a a new starter and some wiring, motor repairs and the compressor needs the head rebuilt with new unloaders (been putting that off for awhile). Fix it all at once is gonna be cash!

7. Originally Posted by H80N
snowbird
.... heck no... dive right in...

we have to know consumption @ pressure

and understand exactly how many cubic feet of air we have in the tank at the pressure that the plasma cutter needs..

AND... Sledsports.... do you have a regulator that will make the pressure your plasma cutter wants..??
Yea, I think I have a good oxy 2 stage Harris out there. I'm not sure if the correct stem is on it tho. I don't know what valve is on the Air cylinder. Haven't picked it up yet.

8. Senior Member
Join Date
Mar 2011
Location
Posts
262
it may be cheaper to rent or buy a small compressor and work with it, slower but it 'll get the job done.

9. The compressor itself has had unloader problems for a while now. I got one unhooked. Its a 2 stage 340 on a 200 gallon tank. I had an electrical issue on the starts the other day and it burnt one of the legs up on the out starter. Cooked the terminal and burnt the wire off. Probably ruined the whole thing. It still pulls together but I'll bet the contacts on that leg is fried crispier than saterday morning bacon.

10. if it is a "J" sized bottle... we are looking at bottle pressure of 2640 PSI = 310 CuFt...Standard Volume (14.7 psia, 70 F)

now we need the conversion formula to convert to volume @ 90psi
then divide by 6.7 cfm

Reference chart

http://www.ohiomedical.com/UserFiles...der%20Data.pdf

Page 1 of 3 123 Last

Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•

Warning: Function split() is deprecated in /mnt/stor3-wc1-dfw1/357822/357839/www.millerwelds.com/web/content/lib/footer.inc.php on line 77

1