3x4 closet flange too loose inside 4-inch pvc pipe?

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3x4 closet flange too loose inside 4-inch pvc pipe?

Author: nicholas123 (FL)

My Oatey 3x4 pvc closet flange fits snugly over a 3-inch pvc pipe, like it should, but it fits very loosely inside a 4-inch pvc pipe.

The OD of the closet flange hub is tapered as you would expect. I wasn't able to measure the thickest part of the hub, but my calipers could reach about 3/4th the way to the thickest part and my average measurement was 3.980 inch.

The average ID of my 4-inch pvc pipe was 4.010 inch, which is within ASTM tolerance.

So after my flange hub is 3/4th into the 4-inch pipe, I still got 0.030 inches (1/32 inch) of clearance between the flange hub and pipe. (4.010 - 3.980 = 0.030 inch) Very loose fit.

So what's going on? Did I buy a flange out of spec?

Re: 3x4 closet flange too loose inside 4-inch pvc pipe?
Author: mr leak (CA) Do C
Post Reply

Re: 3x4 closet flange too loose inside 4-inch pvc pipe?
Author: packy (MA) i have no trouble with charlotte brand fittings and pipe. sometimes mating up pipe and fittings from different manufacturers can cause this. try a charlotte brand 3 x 4 flush fit flange.
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Thanks for the tip, Packy.
Author: nicholas123 (FL) Thanks for the tip, Packy. I tried looking for a different closet flange, but ended up buying a different pipe which was about 15 thousands smaller in ID than the first pipe I bought. Both within ASTM tolerance, but the new pipe fits much better with the closet flange. Edited 1 times.
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