jamesp
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Post by jamesp on Nov 23, 2019 8:28:30 GMT -5
This sch 40 PVC tumbler barrel had been used primarily for coarse grind using SiC 30 and to lesser degree SiC 46. It is about to wear thru at several locations. Not bad for 4 years. The first place to wear thru is the center of the closed end. Cheap X-Ray. Silicon caulk was used to fill the air space between the structural ribs in the reducer on left end.
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Post by knave on Nov 23, 2019 9:42:56 GMT -5
The HDPE barrels have a slower wear rate, correct?
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jamesp
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Post by jamesp on Nov 24, 2019 10:20:15 GMT -5
The HDPE barrels have a slower wear rate, correct? Yes. They are the choice of pipe in mining operations for pumping abrasive slurries. My buddy welded two 4 inch HDPE pipe sections about 3 inches long together a few days ago. We stepped out and beat it with a 12 pound sledge hammer. No resulting damage other than some small dents. The weld stayed intact go figure.
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Post by captbob on Nov 24, 2019 10:36:30 GMT -5
Now why ya figure the center of the end has the most wear? On the Thumler's AR 12 there is a end disk, not sure what it is made of, that wears in the center first. These end lids need to be replaced usually once a year before the center wears through. Seems the outer edges would have more rock contact. Engineer reasoning for center wear?
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EricD
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High in the Mountains
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Post by EricD on Nov 24, 2019 10:57:11 GMT -5
Now why ya figure the center of the end has the most wear? On the Thumler's AR 12 there is a end disk, not sure what it is made of, that wears in the center first. These end lids need to be replaced usually once a year before the center wears through. Seems the outer edges would have more rock contact. Engineer reasoning for center wear? That is the point of most of the movement from the rocks sliding across it as the top rocks slide at an angle downward to the other side.
On mine I used vulcanizing rubber cement from a bicycle tire patch kit to attach a 3/8" thick disc of rubber from a tractor trailer mud flap on the inside. I think the lid will now out-last the barrel, and it cut the noise considerably. FYI for anyone that does this, the cement will actually melt the lid to some extent, so keep it away from the lid's sealing surfaces and wipe it off quickly as it squishes out. Use a heavy flat weight to apply pressure as it cures (24 hours worked for me).
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panamark
fully equipped rock polisher
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Post by panamark on Nov 24, 2019 12:17:51 GMT -5
Now why ya figure the center of the end has the most wear? Seems the outer edges would have more rock contact. Engineer reasoning for center wear? I puzzled on that a bit also Bob. I think perhaps it is because the center is ALWAYS in contact with rocks, whereas the outer edge has a period in each rotation where there is no wear going on (no rocks touching). Over time a 15% "rest period" might really be significant. Just my guess.
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EricD
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High in the Mountains
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Post by EricD on Nov 24, 2019 12:23:40 GMT -5
If you'll notice in the following video, almost ALL of the rock's motion and the highest velocity of the rocks is past the center of the lid:
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Post by manofglass on Nov 24, 2019 18:55:00 GMT -5
This sch 40 PVC tumbler barrel had been used primarily for coarse grind using SiC 30 and to lesser degree SiC 46. It is about to wear thru at several locations. Not bad for 4 years. The first place to wear thru is the center of the closed end. Cheap X-Ray. Silicon caulk was used to fill the air space between the structural ribs in the reducer on left end. I replace the cans before they get that thin If I can squeeze the can it is time to make a new one
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jamesp
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Member since October 2012
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Post by jamesp on Nov 25, 2019 1:46:22 GMT -5
Now why ya figure the center of the end has the most wear? Seems the outer edges would have more rock contact. Engineer reasoning for center wear? I puzzled on that a bit also Bob. I think perhaps it is because the center is ALWAYS in contact with rocks, whereas the outer edge has a period in each rotation where there is no wear going on (no rocks touching). Over time a 15% "rest period" might really be significant. Just my guess. The rocks are constantly in contact with the center and rub on it constantly. Instead of staying in contact without slipping on the outer wall or of the barrel. The rubbing action at center can be seen in 'properly filled barrel' in EricD's video. In the PVC barrel there is extreme wear at the shoulder of the reduction from 6" to 4" starting 2 inches into the 6" section from the reduction. Had they had added a clear properly mixed sticky sugary syrup slurry in that video so one could see the rocks rubbing against each other instead of rolling each other.
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jamesp
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Posts: 36,154
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Post by jamesp on Nov 25, 2019 2:08:05 GMT -5
This sch 40 PVC tumbler barrel had been used primarily for coarse grind using SiC 30 and to lesser degree SiC 46. It is about to wear thru at several locations. Not bad for 4 years. The first place to wear thru is the center of the closed end. Cheap X-Ray. Silicon caulk was used to fill the air space between the structural ribs in the reducer on left end. I replace the cans before they get that thin If I can squeeze the can it is time to make a new one Yes they can be squeezed when the walls wear thin Walt. The next set of PVC barrels I built I cut "piston rings" out of pipe about 2 inches long and glued them inside the pipe at each end and at the center point where the wear was highest. By sawing a gap out the 6" pipe and compressing it to fit inside the 6" pipe. Basically a pipe in a pipe. I also cut a 6 inch diameter plate out of sheet PVC and glued it into the end cap before glueing the end cap on. Cheap additions that about doubled the life. Barrel got heavy with so much plastic and most of the barrel was closer to 5" inside diameter. A bit labor intensive, cost about $45 per barrel. A 6 inch HDPE SDR end cap and a 6 inch HDPE SDR 6"x4" reducer cost $70 and takes 15 minutes to weld and last a very long time. The one on the left is the size the 6" fittings come from the factory. Best to cut the 4 inch snoot shorter.
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Post by manofglass on Nov 25, 2019 8:13:35 GMT -5
I cut a 4” hole in one end cap for a 4” test plug Then glue the caps on I cut the 6” pipe on a lathe
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jamesp
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Member since October 2012
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Post by jamesp on Nov 27, 2019 5:41:12 GMT -5
Very novel idea manofglass. I have never seen such a test plug. Those wood bearings are still rolling, brilliant ! Never under estimate the capability of wood bearings !:
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Post by orrum on Nov 27, 2019 6:43:48 GMT -5
Great pics Jim!!!
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Post by manofglass on Nov 27, 2019 11:47:07 GMT -5
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jamesp
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Member since October 2012
Posts: 36,154
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Post by jamesp on Nov 27, 2019 12:21:38 GMT -5
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Post by orrum on Nov 27, 2019 21:23:40 GMT -5
We r good Jim. Traveling differentb roads now but we stay in touch. You sure got a bunch of BIG projects going on!!!
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jamesp
Cave Dweller
Member since October 2012
Posts: 36,154
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Post by jamesp on Nov 28, 2019 7:27:27 GMT -5
A one screw expansion plug. This is a great idea manofglass.
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