Can a bad swirl ring cause a misfire?

[smutboy420]

I have had a problem pop up in the last few days were every few pierces my torch fails to fire on my hypertherm powermax 30 Usually if I restart it will refire. Then it will cut again but after a few pierces and cuts it will do it again. Its getting pretty aggravating. When it happens I can hear the relay for the torch click and I get a tiny tiny bit of air come out of the torch and also can see a tiny spark start as if it wants to start but it dont then the torch clicks off and the light on the cutter that normally turns on when ever you take the cap off comes on but instead of staying on solid it blinks and if I get the torch to fire again it turns off. With out having to turn the power switch off and back on. and twice yesterday it got to the point that the torch just would not fire at all many times in a row. Even when I tried hand fireing it. Then i took the cap off and looked at the electrode and nozzle and they were still fine but after putting every thing back together the torch would fire again for a few cuts then it started doing the random misfireing thing again.

I have been trying to trace the problem down and I THINK I MAY OF FOUND what it is but not sure and wanted to run it by some one here. I notice the electrode dont slide as smoothly up and down in the swirl ring as it used to. and thats making me wonder if I have a bad swirl ring causing the electrode to not pull back properly to start my arc. and thats the only thing I can find that seems to not be as it should........ So I'm wondering if this has happened to any one else before and did a new swirl ring solve the problem?????????? and thanks in advance to any one that can shed any light on this issue.

[jimcolt]

Here are the things that will make your Powermax30 misfire:

-Worn electrode and nozzle. (the operators manual show how to inspect these). Sometimes cleaning the oxidation and discoloration off the end of the electrode and the inside of the nozzle (electrode and nozzle have to make electrical contact here) with a scotchbrite pad will provide for a few more starts on a worn set.

-Overtightened retaining cap. Just snug it....it has an o-ring seal, so does not require a lot of torque. Overtightening cause the electrode to bind in the swirl ring.....misfire is the result.

-Worn swirl ring. The electrode must slide freely inside the swirl ring. If not, replace it. If the swirl ring has burn marks or cracks....or the holes are distorted, replace it. These all will cause misfires.

-Dirty torch. Clean all inside surfaces. Dirt and grease will cause misfires as well as torch damage. Keep the inside clean.

-Aftermarket consumables.....wrong materials and way out of tolerance. Misfiring, torch overheating are the result. Use Hypertherm parts....they may cost a little more but they last longer....meaning lower cost per foot of cut.

- Incorrect inlet air pressure. Too high, too low will cause misfire.

-Moisture or oil in your air will cause misfiring.

-Inadequate inlet power. If you are running on a 120 volt power line.....and an extension cord that is longer than 50' and has conductors smaller than 12 gauge...the torch will misfire.


Jim Colt Hypertherm

[smutboy420]

Thanks JIm I tried cleaning the insides or the torch head with a soft pcs of cloth and I also replaced the electrode and nozzle and just because the electrods have been sitting in a drawer for over a year I hit the back and the front end with a scotch bright pad just to be sure there was no oxidation causing any thing. My air is good and dry and also oil free. I have a large desiccator drier in line. Nothing has changed with my power its plugged right in to the wall socket with no lead cords or any thing else in my set up changing at all.

Tho even cleaning the in side of the swirl ring and even with the cap screwed on very gently its still miss firing and Being today i was trying to do some hand cutting and was still doing it. But I noticed when it did if i bumped the torch just a tiny bit it would work again every time. So I think its got the be the swirl ring causing the electrode to bind. and was going to go pick up a new one today at the welding supply place. But now I think I may have some bigger issues going on and may have damaged some thing else from all the miss fires. Because now even when i get the torch to fire it dont cut right. Its acting almost like when you forget to put the work clamp on the pcs and instead of cutting threw it just sprays sparks all over the place. unless I cut my speed down to less then 1/2 of normal. Its really freaky I was doing some cuts that I was doing yesterday and even on the same sheet I was working on just yesterday and when it dont miss fire It will start each cut and the first inch or so will go ok and go threw the metal then start spraying just like its got no work clamp hooked up unless I go super slow which i never had happen before and yesterday I was getting good cuts at the 82ipm on these cuts and that plate now today I had to go down to 36 before it would stop spraying sparks and slag all over the top side. Which at first I thought oh i must not have a good connection with the work clamp. But I even checked with my mutl meter and I got continuity if I touch the work lead and any were on the plate. I also always hit the corner with the angle grinder were I put my work lead and I also hit the inside of the clamp with some sand paper to make sure it was not corroded.

[smutboy420]

Dont know what was going on earlier. But after calling it quits this after noon. I went back out and scotch brighted the crap out of the electrode and also the inside of the retaining cap and even cut a tiny pcs of the scotch bright pad and cleaned the inside of the swirl ring and the silver colored thingy that contacts the back of the electrode Then the weird cut problem were it was not cutting threw and acting like it had a bad work clamp connection seemed to of gone away. Still had a few miss fires but only about 1 or so every part I cut. Which was tolerable till I can get a new swirl ring.

[gary42095]

make sure you have a good ground, just because your clamped to the work piece does not mean it is a good ground try the scotchbrite on the piece your cutting at the clamp. i have had a few issues in the past with that and hand cutting.

just something to double check

edit i see you clean work piece dohhhh

[jimcolt]

The swirl ring in a Hypertherm torch :

-Is the insulator between the negative electrode and the positive nozzle. As it wears it can get burn marks (carbon) that are electrically conductive....this can allow arcing between the electrode and nozzle and can cause misfiring.

-Acts as a bearing that allows the electrode to slide freely inside the torch. This is a blowback torch...meaning the electrode blows back (air pressure) away from the nozzle creating a short circuit spark to ionize the air....which starts the plasma process. A worn swirl ring will not efficiently allow the electrode to slide, the torch will misfire.

-Controls the air flow to the nozzle and swirls it an accurate rate to improve nozzle life. A worn swirl ring will allow incorrect air flow to the nozzle.....which will promote misfiring and short life.

Cleaning the plastic (Dupont Vespel, a high temperature, high dialectric insulating material) swirl ring with a scotchbrite pad will likely cause more misfires due to the roughened edges as well as dimensional changes. The swirl ring is a high tolerance part. When it wears out it simply needs replacement. You should always have a spare swirl ring (new) available. The swirl ring, if kept clean, typically will last for a few hundred thousand starts! Don't cheap out by trying to get more mileage out of it.....it is only costing you a few penny's for each hundred feet of cut.

The retaining cap (over time) will also wear out. Try a new one. Do not overtighten. Check the oring that seals the cap to the torch body.

Jim Colt Hypertherm

[smutboy420]

It definitely looked like some sort of carbon build up that was in the swirl ring cleaning it out bought me some time to at least finish up my last few pcs I was doing to get me by till the new one arrives. I also started getting some very nice cuts again to very little slag and curfs that were pencil line thin. But still miss firing every once in awhile. But I may run down to the welding store and get one today and keep the one I ordered as a spare. Being just the down time waiting for another one someday again when it needs replacing is not worth the few dollars saved by not havering a spare on hand. I think I will also get a new cap to so that if and when that needs replacing I will have it on hand also. screwing around trying to get something to work temporally is just not worth the $ saved to try and get a few more cuts out of any consumables. Id rather spend my time cutting good pcs then screwing around or swearing at my machine

[CNCCAJUN]

I have come to the conclusion that I need to view consumables like "FUEL" & The PowerMAX as the vehicle.

With my the little experience I have seen first hand the difference in "ready for the can" consumables & new ones.

Steve