China clone go BOOM !!!

[Hoosier Daddy]

Is the chunk of connecting rod still on the wrist pin seized / gaulded to the pin or merely put in place to show the catastrophic failure?

[cosmic]

No just enough of it to hold on the wrist pin..

[Hoosier Daddy]

I think that is the failure point and the piston slamming into the head blew out the jug.... (Cylinder)

Wow... you really coulda died there.

[avator]

Tell ya what....
I have the MRodair Airmax Extreme MKII. It's a dual piston like the AV. I've been filling my 3300 psi scuba tanks with it. Maybe 4 fills since service. I have a SCBA 30 minute 4500 tank coming next week. I think I'll do a service on mine before I make my first 4500 psi fill. Oil and filter changes. Then I run slow with rest stops for the first time. I've never had an issue as of yet but I feel the need to be cautious.
P.S, PPE will be in play.

[rsterne]

I think Travis is right, wrist pin end connecting rod failure.... The HP piston (which is rigidly connected to the LP piston, right? ) kept the LP piston straight in the bore and prevented much galling.... The broken rod probably drove the LP piston into the end of the cylinder, pushing it out the top by breaking the bottom of the cylinder.... My guess, anyways....

Bob

[oldpro]

Travis do you think y'all will be able to get the 3 stage SPA, these small compressor's aren't really cut out for filling tanks IMO.  I can see doing a little at a time but extended sessions is probably what's killing them.  If I ever get one of these small compressors I probably wouldn't use it for filling tanks, just guns directly.

here's a REAL compressor

Yes were working on the details

[MJP]

Just simple physics, you double the load of the original design and expect it to last?
All of these pumps are build on a regular one or two cylinder shop compressor frame, designed to run max 10bar. And then added a new head with extra piston.
Now you have two work loads on the same crank and rod designed for the single piston at 10bar and have 10bar x piston area plus 300bar x small piston area! And you wonder why it blew up?

Marko

[rws_53]

Just simple physics, you double the load of the original design and expect it to last?
All of these pumps are build on a regular one or two cylinder shop compressor frame, designed to run max 10bar. And then added a new head with extra piston.
Now you have two work loads on the same crank and rod designed for the single piston at 10bar and have 10bar x piston area plus 300bar x small piston area! And you wonder why it blew up?

Marko

lots of them out there....they should all be blowing up by now

[bandg]

I'll stick to filling gun cylinders only to 3k with the small compressor-they seem to work well for that but could still fail.  I think I'll be making a scattershield to put over the compressor when running as well.  As rws_53 notes, the actual failure rate may not be that high considering how many are in use and the number of failures that have been reported but any such failure could easily cause injury.  I'm now thinking I'll plan to buy a Daystate or Airetex compressor since they seem to have much more robust engineering and seemingly should last a lifetime for air gun use.

[MJP]

Just simple physics, you double the load of the original design and expect it to last?
All of these pumps are build on a regular one or two cylinder shop compressor frame, designed to run max 10bar. And then added a new head with extra piston.
Now you have two work loads on the same crank and rod designed for the single piston at 10bar and have 10bar x piston area plus 300bar x small piston area! And you wonder why it blew up?

Marko

lots of them out there....they should all be blowing up by now

More time passes and more will fail, but what do I know, I'm just an engineering student with over 25 years of work experience in mechanics and prototyping.

[bandg]

Personally, I think the small compressors are working at the edge of the envelope for filling 4.5k tanks.   Hopefully, 3k gun fills will not be as much of a problem.  It will not be that difficult to make a metal box with vent slats to sit over the compressor-this would allow air flow but should contain any flying debris from any failure.  I have a local fire station that fills my GW tank at this time but will be purchasing a more stoutly engineered compressor for tank fills in the future. 

[Hoosier Daddy]

3k gun fills will not be as much of a problem.

That is what I am banking my money on... and 3000psi paint ball 48ci bottles.
If it holds up to those I am happy.
 

[bandg]

Same here.  But I'm still making a metal cover.