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wierdscience
05-03-2006, 12:17 AM
A friend and a good customer of mine had a write up in the paper the otherday.
I knew he had a prostetic leg,but never knew how he got it.

The news paper editor got the cause wrong,it was corrosion that was the culprit,read on-

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When the only place to look is up

By Brooke Westbrook/Item Lifestyles Editor
Saturday, April 15, 2006 5:59 PM CDT



“Life can take you by surprise and when it does, you just have to go with it,” said Linda Graham. “Your next breath is not determined by you. It's determined by God.”

On January 12, 1983, when Wayne Graham was 23 years old, life definitely took him by surprise. It was 9:15 a.m. and the temperature was six degrees. Wayne was on his way to work and stopped at a gas station, owned by Frank and Gloria Smith, on Hwy. 11 in Derby. Arthur Savage, one of the first soybean farmers in the area, was working on the Smiths' car in the parking lot of the gas station.

Wayne was going to air up the tires on their car, but someone had stolen the air line from the air compressor at the store. He decided to go down the road and get another air compressor. He turned the 35-gallon compressor on and checked the pressure on the tank. Wayne was squatting about two and a half feet in front of the tank and just when he started to stand, a frozen valve caused the air compressor to blow up. That was the moment Wayne's life changed.

The explosion of the compressor blew off his left leg. Arthur, who was standing nearby, was hit by something in the face. “I tried to get up and help him,” said Wayne. “He was on his knees and elbows and I asked if he was ok. He had just come over there to help me. If he had come ten seconds later, he wouldn't have gotten hurt.”


The explosion was so strong, it was heard eight miles away. They waited almost an hour for an ambulance. “I told them to take me straight to Forrest General, but we went to Poplarville first,” said Wayne. “They got me stabilized at the hospital and I remember my dad walking in. Just as he came in, it was as if he was seeing a deer in a headlight. I told him to just walk out. We were both very emotional.”

Wayne was then transported to Forrest General Hospital in Hattiesburg. He saw Arthur being wheeled by in a wheelchair. “His face was the size of a basketball. The explosion disfigured him,” he said. “Before he even made it to the hospital, the ambulance he was in had an accident on the highway because of ice on the road. The ambulance that took me to the hospital had to turn around and go pick him up.”

“My hospital room in Hattiesburg was full of flowers from people,” said Wayne. “They finally gave me a bigger room so they would all fit. I had a shoebox full of get-well cards. I remember one lady sent me a card every single day.”

Wayne was at Forrest General for six weeks. “I was patient of the month there,” laughed Wayne.

“The reality of the whole thing - that I was disabled - had not really set in with me. After I settled back down at home, work was something I needed to do. I went back to work for about three weeks before I got laid off. I didn't think of myself as handicapped. They laid me off with no excuse. I did basically everything then that I had done before.”

Before his accident, Wayne lived for the weekends. But after losing his leg, he felt he didn't fit in with the same people anymore. “So then it was just me and my family,” he said.

“I was without a leg for about a year and a half. My dad said he would buy me a prosthetic leg, but I wouldn't let him because it was $21,000,” said Wayne. “I didn't have a job to pay for it.”

At that point Wayne started a nursery, which led to the bark business he has now.

“My aunt came one day and took me to Poplarville to meet a man about a rehabilitation program that would buy you a prosthetic leg if you qualified. I didn't want a hand-out because I had too much pride,” said Wayne. “Then I realized that was what those people were there for - to help people in situations like mine.”

Wayne qualified and was sent to Mississippi Methodist Rehab in Jackson, where he learned how to walk on his new leg. “I didn't think it was possible to walk on it,” he said. “But pretty soon I was walking and chewing gum at the same time!”

“They didn't want you to stay in your room all the time there. They wanted us to go to the cafeteria and eat if we could, instead of staying in bed. Going to the cafeteria really opened my eyes,” said Wayne. “When you got to the end of the food line, there were volunteers waiting to take your tray to your table for you. These people don't get paid anything, yet they were always so cheerful and talkative. You sit down at your seat and you don't know a soul, but all at once you start to realize other patients in there are having to be fed by someone else. I would sit there and think, ‘just last week there people were probably feeding themselves and now they're here.' I would get tears in my eyes, because I was taking for granted the ability I did have. My injury was so small compared to those people's.”

“The rehab was one of the best medicines I could've had. I came home a different person,” said Wayne.

Wayne is not on disability because he feels as long as he can still work, he does not deserve to get disability.

“I've had people look at me and I can tell they're thinking that they're so sorry I lost my leg,” said Wayne. “And I think, don't be sorry. I would've probably been killed going down the road I was on.”

The Graham's now live their lives as a testimony to others - they believe that no matter what trials you may face, God can still use you to serve Him.

They were recently recognized by their church, First Baptist Church of Carriere for their inspiration to others.

“We've been blessed,” said Linda. “And we have to give God the glory.”

Instead of getting discouraged when nothing seemed to go their way, Wayne and Linda Graham looked up and found their answer.

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He keeps the remains of the tank as a reminder,the wall thickness of the tank was 3/16" and a narrow stripe in what used to be the bottom was nearly rusted through even thou the outside looked fine.

The tank has one of the headers still attached by a thin shred, the other header was never found.

They don't know exactly what hit Arthur,but judging from the brusing that was present they think it my have been the motor.

Keep an eye on those compressor tanks,if there is any doubt replace it with a new one.

Millman
05-03-2006, 04:14 AM
Hate to hear about accidents like that. Seen quite a few, but not that one. I think we all better go out and drain our tanks!

madman
05-03-2006, 01:29 PM
I met a fellow years ago with the most horrendous scars on his chest and arm. It happened one morning he told me when he was turning on (big ball check valve) the main air feed for the big plant. He was just moving the lever and boom. Blew up real good. Messed him up bad. Innocent thing like a compressor could become a improvised explosive device so to speak. Caution in the shop advised and perhaps a closer eye kept on seemingly innocent hunks of equipment. Take care Mike

Leigh
05-03-2006, 01:53 PM
The problem is that corrosion occurs inside the tank. Anybody know of a reliable way to assess the condition of the tank wall?

Evan
05-03-2006, 01:56 PM
There was a real bad picture floating around a while back of a guy that had been filling an aircraft tire, big one, and left the air clipped to the valve. It blew up and cut him almost in half at the midsection.

Evan
05-03-2006, 01:56 PM
The problem is that corrosion occurs inside the tank. Anybody know of a reliable way to assess the condition of the tank wall?
Hydrotest.

jr45acp
05-03-2006, 02:19 PM
Weird,

Thanks for posting this. Reminds me of a guy who applied for a correctional officer position when I was working at the Federal Penitentiary in Leavenworth, KS. The department head for correctional services told him that he didn't qualify because he had a prosthetic leg. The prospective employee took that guy out in the hall and ran up and down the hall without difficulty, then said to the department head, "If you can do better than that, then don't hire me!" He turned out to be a great employee and an even better friend.

I believe we all have some degree of disability, and speaking only for myself, the greatest is failing to see things through the eyes of those less fortunate than us.

Again, thanks for the post.

Kansas_Farmer
05-03-2006, 03:04 PM
Hydrotest.

Ultrasound
http://www.phase2plus.com/pics/UTG-1000.jpg

Evan
05-03-2006, 03:05 PM
It's pretty hard to do an ultrasound test under the installed components like the air pump and motor. Hydrotest is how you tell if the tank will hold.

Kansas_Farmer
05-03-2006, 03:07 PM
Oh I know....I do this every year....I know all about it. If ya can't get to it, ya take whatever ya have to off....

Removing the jacket from 1917 Steam Engines to ultrasound the barrels isn't any fun, specially when they haven't been off since the war.

Evan
05-03-2006, 03:10 PM
the greatest is failing to see things through the eyes of those less fortunate than us.


Yep.

http://vts.bc.ca/pics/froglegs.jpg

Timleech
05-03-2006, 03:43 PM
It's pretty hard to do an ultrasound test under the installed components like the air pump and motor. Hydrotest is how you tell if the tank will hold.

Under the installed components is probably the *least* likely place to have dangerous corrosion, I would think. That's most likely to happen near the bottom.
Last time mine was 'done', the surveyor just did a visual internal with the help of an endoscope, a torch and a mirror.
Many surveyors of the old school regard ultrasound as a way to confirm an opinion they've formed by other means, rather than the foundation for the whole survey. I'm talking particularly about steel boat hulls, but I've seen the same in other fields.

Tim

Kansas_Farmer
05-03-2006, 04:30 PM
Which is a fairly common thing to see in things like this. The old ways are no longer taught to us new guys, so we only learn how to use the new tech, none of the ways to do it without the tech are brought up anymore. So when tech fails us, we're SOL. I'd like to know all the old fashioned tricks too....I know a few, but not nearly enough.

dicks42000
05-03-2006, 08:27 PM
Kansas farmer....looks like a D meter to me. Yep, used to test wall thickness of tubes, shell plating, & hull plating. (Been a few years since I used one myself.)
Wonder where Charlie Coghill is & how's his boats boiler...?
Evan...hydro testing is OK, but in the case of a boiler or other pressure part, it won't always show potential damage/ hazards/ incipient failure. Think of welds & "reinforcement" required by an inspector on a sweet water condenser for a certain pulpmill I know....Guy wouldn't believe me that what he wanted was not good. (Welds subject to saturated steam are weaker than dry, room temp. test samples...) Passed hydro test fine, failed in field. Fortunately didn't hurt anybody....My original design was used 2nd time around, still was working until the mill (Woodfibre, Squamish BC.) was closed. (See Prof. Gordons books for an example...)
A couple of excellent books on structures, simple theory & much other interesting engineering & materials science stuff are "The New Science of Strong Materials" and "Structures or why things don't fall down" by Prof. J.E. Gordon.
He is/ was a fascinating old guy. Former Naval Architect, researcher at Farnborough during 1940's, materials scientist, accident investigation consultant, sailer, skier, etc. I like his style & sense of humour, too.
Lots to say about back shops, things that blow up, fall down & maime people, & people who don't take care to do research, as well as some engineer collegues.
Enjoy & make chips.
Rick

Evan
05-03-2006, 09:27 PM
This isn't about boilers or other pressure vessels that operate at elevated temperatures. The standard test for air receivers is a hydrostatic test. This is standard practice throughout industry and is called for by regulation.

charlie coghill
05-03-2006, 09:35 PM
****s I am right here. My boiler is only about three years old but it gets a hydro test every year and always will.

matador
05-03-2006, 09:39 PM
After use ,I always open the drain valve,and leave it open until I next use the compressor.Is this a good idea?Usually when i drain it,a bit of water comes out.My theory is this water is better on the floor than in the tank.Will this prevent corrosion,or actually promote it?Your views will be appreciated.

x39
05-03-2006, 09:47 PM
A friend of mine had a home made compressor grenade in his basement, fortunately no one was near it when it went. It caused quite a bit of damge to his house though.

wierdscience
05-04-2006, 12:10 AM
What has me worried are the new tanks on the market.The one that blew on Wayne was probably 30 years old and was 3/16" thick,not long ago a customer brought in a new tank off a compressor he picked up at the scrapyard(Cambell Huasfeld,rod through the pump).

He had me cut the endbells out so he could use the tank for the shell on a Gingrey furnace he is building.The walls where only 14 ga at best:eek:

I have an airless and a 5hp two stage,I think both are going under a lean-to outside the shop,it'll be a little more quiet anyway.

dicks42000
05-04-2006, 11:37 AM
No, I didn't mean to hijack the thread to boilers. We were talking about surveying metal thickness, things that blow up, and trying to stay safe around pressure containment though.
I'm going to go drain my air reciever manually just to check on how well the auto drain works....
Good comment about the newer store-bought tank, Weird....
Maybe the shop compressor should be in a lean-to...

Evan
05-04-2006, 11:58 AM
The main corrosion causing factor in a compressor is not just the water, it's the oxygen partial pressure. At 125 psi the oxygen partial pressure is at 25 psi compared to about 3 psi at STP. That is like having pure oxygen in the tank at STP and greatly accelerates corrosion. That is one of the reasons for using nitrogen in tires as it prevents the oxidation breakdown of the tire compounds from pressure oxygen.

Millman
05-04-2006, 12:08 PM
it's the oxygen partial pressure. Just think, all this time I didn't know you had to install a seperate valve for the OPP. Always opened the valve and let the water and air out. It's amazing what a guy can learn!

Evan
05-04-2006, 12:24 PM
Millman,

If you can design a valve to let out just the oxygen you will be rolling in clover. If you get it to work I want 50% for giving you the idea.

Millman
05-04-2006, 12:33 PM
What..you mean you haven't designed one yet?

J Tiers
05-04-2006, 02:25 PM
Am I right in assuming the one referenced in teh original post was a stand-up type?

Most all the tank failures I have heard of "for real" (not internet legends) have been pretty "soft" failures, they started to leak in corroded areas, etc. May have hissed pretty loudly..... even jumped as the air let loose, but didn't blow and fly for the moon.

And, I wonder if corrosion AND the 6 deg F air temp may have conspired to cause a quick cracking, and not the usual "soft" failure. Most gas stations / repair joints don't waste a lot of money on heat out in the shop areas.

It's even possible that un-drained water froze in it and already stretched/cracked it, and it blew when the ice melted from the heat of compression plus being loosened by vibration.

Lots of things we don't know about the details.

flatv8
05-04-2006, 08:11 PM
One of the things that I see at work on our locomotives, is that they drill holes part way through the tanks walls. This is done on various places on the Air tanks, especially on the bottom. The idea is that if the tanks starts to rust, it will start to leak at one of the holes first, indicating that you have a problem. Why not do this on home compressors as well? I assume that if you could find out the wall thickness, would you drill half way?

wierdscience
05-05-2006, 09:26 AM
Well there is Eddy current testing,although I'm not sure how you would get the magnet probe into the tank.

J,no this was a horizonal tank,I don't have any doubts that it cut loose all at once,it's the second time I have seem the results,first one was a 40 gallon tank that took two back walls and anything light enough to move out of a mechanics shop here in town.

The temps may have played a hand in in the accident,it's possible that the pressure switch froze and the pump kept running past the cutoff,Wayne says he doesn't remember if the pump switched off or not before it blew,but it was still due mainly to corrosion.

J Tiers
05-05-2006, 10:21 AM
I don't see that as a "ductile failure", it sounds like a fracture. Even corrosion shouldn't do that, in fact it should blow out thru the rusted area and leave the rest. Sort of a safety valve......

I think it had to be an overpressure, or a tank pre-weakened by freezing of water, etc.

Still a good point though.

halac
05-05-2006, 01:09 PM
After reading the previous posts I decided to go out and check my air compressor for water last night.

I think the last time I did this was at least five and maybe more like ten years ago.

I live current in central Florida and you would think there would be quite an accumulation of water due to the high humidity we have down here. When I opened the drain I got less than half a pint of fluid out. I was pleasantly surprised.

Sometime in the next month or two I'll be moving this A/C to Tennessee. Once I do move it, I'll be putting on an automatic drain valve, just in case. :D

Evan
05-05-2006, 01:38 PM
The temperature at 6 degrees F most certainly played a role in the catastrophic failure of the air receiver. Mild steel exhibits ductile brittle transition at -60 degrees but it isn't a sharp knee curve. The Izod impact strength of mild steel begins to drop noticably at around freezing and at 6F is reduced by about 25%

This means that any existing microcracks would be that much more likely to fail by brittle fracture than ductile tearing and without doubt contributed to the failure mode.

Millman
05-05-2006, 02:46 PM
{Mild steel exhibits ductile brittle transition at -60 degrees but it isn't a sharp knee curve. The Izod impact strength of mild steel begins to drop noticably at around freezing and at 6F is reduced by about 25%.} Evan, there you go again dabbling in theoretical physics. Next time we drain the water out of our tanks; should we REALLY be concerned about the Izod strength?

Evan
05-05-2006, 02:50 PM
Nothing theoretical about it. They stop the trains around here when it gets to -40 because the rails fracture.

Millman
05-05-2006, 02:53 PM
What....Canada can't afford the better Chinese steel? Who would have thunk it!

jdunmyer
05-05-2006, 03:01 PM
Someone mentioned the possibility of the switch's freezing: I had that happen on mine and it scared hell outa me! I fortunately realized what was going on before it was too late and shut 'er down. Now have a pressure relief valve installed on my home-brew setup, which I did not have before.

Allan Dimmock
05-05-2006, 06:20 PM
http://i63.photobucket.com/albums/h139/adim031262/FrivStuff/izal_toilet_paper.jpg

Izod's brother took material strength research to another level :)

Seriously, I am concerned about the tank on my compressor. Is there likely to be corosion inhibiting coating on the inside of the tank ? Mine is a cheapo Italian made Clarke compressor, but I believe it has been made to a reasonable standard. I drain it down regularly and have always expected the tank to outlast the compressor. How concerned do I need to be? After all, I am following the manufacturers instructions.