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Rotary airlock on cyclone hopper?1/16
I have an outdoor cyclone on top of a 103 CU FT hopper. Currently, we have to manually open a slide gate underneath to dump into a trailer. With the vibration of the cyclone running all day, the chips and dust bridge over and have to be poked at with a long offrip to release everything. This ends up being a messy job if the wind is blowing.
I'm thinking about going to a rotary airlock to replace the slide gate. I have a couple of questions about them in general:
1. Because they run continuously, there shouldn't be a bridging issue as long as it is sized to handle big demand, like the moulder. Is this true?
2. How much backflow should I expect with a six vane unit, and will this cause the afterfilters to see a higher load and need more maintenance?
3. When temps are freezing outside, will ice build up inside and cause problems?
4. What else should I know before I make this move?
With the correct size air lock there should be virtually no buildup / backflow. The filters may stay cleaner. There should be no ice problems.
The big key is to get the correct size. Beyond planers and moulders most tools don't put off chip that fast.
I would not buy one used, call a pro and spend the $ once.
We've got a 12" rotary valve on our cyclone. It handles our molder easily. I've been surprised how long the vanes last, many years. Ours drops the shavings directly into the trailer through a canvas tube with a plastic window so we can see from inside the shop when the trailer needs moving. When I had the cyclone made I had a cleanout door put 3' above the airlock. If they fail to move the trailer in time it backs up & bridges in the cyclone. There are 3 parts to maintain regularly: lube the chain, grease the bearings, check the oil on the gear box. Many of them are installed open to the weather, I put a protective cover over ours.
JR, tkae this with a grain of salt, as I'm currently not using an airlock, so everything I think I know, is just from reading, speculation, and from not paying enough attention to that part of things when I worked for other shops.
I think it's a must have for any shop that is constantly making chips. It also opens up other opportunities for handling the chips after the airlock. You can just drop them into a dumpster or barrel, or you can blow them into a trailer or bigger dumpster.
If it's running whenever the dust collector is running, it bridging shouldn't be an issue. Putting it on a timer so it runs for a bit might not be a bad idea though.
The amount of air coming back into the cyclone won't be much.
I don't remember any issues with ice and snow at the shops that I worked at. This is minnesota too.
I'm probably just defending my position on this, I bought a 12" Torit airlock for my bag house for $200. It is a wreck. The gear box is most likely not salvageable, it's missing the motor, it's missing the chain, and I'm guessing the bearings need to be replaced. It needs a compete rebuild.
Something I have been considering is instead of running a gearbox to get it down to 40 rpm, and another reduction through a chain to get it down to 10 rpm, I'm kicking around putting a brushless motor on it and deleting the first gear reduction. Less moving parts, plus the ability to adjust the rpm a little bit to better match input. At this point that is just a thought and I haven't dug into it any deeper.
Another thing to consider is a grinder for your scraps. If your sucking ground up scraps and drops out to the cyclone, and blowing them into something else, your handling of waste should be dramatically less. Just blowing ground up bits into the cyclone likely isn't saving you anything if you have to handle it again.