06 April, 2016

Don't leave air hoses plugged in, and air compressors turned on

So over the weekend, I was doing shop cleanup, using the blow guns, and of course filling tires. I forgot to disconnect the whip that connects the compressor to the mainfold, and I left the compressor on and forgot about it. 
Well, I had to run some errands yesterday, I wasn’t out of the house very long. Maybe 2 hours. Well I came back and from the driveway I could hear it…
Air compressor was flailing away and there was a constant FAST hiss coming from the shop.
I know what that sound is!
Go in to the shop as fast as I can, it’s hot in there, I flip the switch on the compressor to shut it down, and disconnect the feed hose to my manifold.
Right where the hose bends to go up to the manifold there is very clearly a 1/4” long tearout in the hose.
Now mind you, all of my hoses except for my Hitachi, came from Harbor Freight. Now before anyone goes bashing Harbor Freight, mind you I have a LOT of experience with compressed air systems, and hoses. The BEST air hoses I have used hands down have been Goodyear, the black ones.
This experience was back when I was a MUCH younger man, and gas stations actually had full service. I managed one for several years, and we averaged a 12 month time to failure on hoses. My home garage workshop use has been, well I need to verify but I believe it has been 26 months since I set up the reel / manifold rig, and I leave it pressureized and connected WAY more than I ever did in the gas station.
Now like I mentioned, I was only out for about 2 hours, and the hose wasn’t blown out when I left, so some time in that 2 hour time frame, the hose blew, the compressor kept running, and it produced enough heat to heat up the shop to over 90 deg F.
This could have possibly led to a shop fire, and considering my shop is attached to the house, this had the potential to be REALLY bad.
Lessons learned?
#1. ALWAYS disconnect the feed whip when done with the system for the day. I am considering a simple ball valve on the feed line to keep things connected, and moist air out of the filter / dryer. #2. Turn the compressor OFF when not likely to be used that day. #3. Drain the compressor tank FAR more often than I do. I never neglected to do this to the big 60+ (Actually a bank of 4 120 gallon compressors) on a daily basis, but their drains were a LOT easier to get to. I will end up extending the drain out with a ball valve so all I have to do is flip a ball valve open instead of reaching way back in and under to get to a petcock valve that instantly spews every bit of shop dust into your face.
Now the question is… How to approach fixing this disaster next?
Step #1. Gather supplies. First I need 2 1/4” full port ball valves.
http://www.harborfreight.com/14-in-full-port-ball-valve-68254.html (I already have one).
Will need one 1/4” NPT male x female brass elbow.
Need 10” brass 1/4” NPT nipple. Can’t find a link, but I know my local Lowes has them. That’s where I got mine.
3/8×8 – 15ft air hose remnant. (Useful for whip hoses).
#2. Disconnect the compressor from power. And pull it out of its cubby hole. #3. Remove the quick connect from the outlet port on the compressor. Treat the threads with pipe dope, and install the first of ball valves, Install the quick connect on the ball valve. #4. Transfer over the quick connect fittings from the blown hose to the new one. #5. Dry out the dessicant beads, seal them up while I finish the rest of the work. #6. Remove the petcock valve from the bottom of the compressor tank. #7. Pipe dope the male of the street elbow, and install it onto the tank insuring the female threads point back toward the wheels. #8. Pipe dope both ends of the 10” nipple, Install the second 1/4” ball valve onto the nipple, install the assembly onto the street elbow.Close all valves, check for tightness. #9. Reconnect to power. Power on and test fittings for leaks. #10. Assuming step #9 passes. Move compressor back into place, replace dessicant in dryer / filter, and reconnect whip hose. Open output valve, Check for leaks. #11. Close output valve, turn compressor off, and open drain valve to bleed tank. #12. Create, print, laminate, and post compressor operation / maintenance procedures on cabinet behind compressor.
Step #12 is for my wife since she may end up having to know how to turn the compressor off in an emergency.

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