Has anyone ever threaded this type of conduit. I am going to use it for an upcoming job at a waste water plant. Is it threaded any different than regular rigid conduit? Do you have to remove some of the coating to thread it or do you need any special tools?

Yes Master,
"As river flow in spring time, so shall many shaving flow from pvc coated pipe."
I've threaded much of the dreaded pvc coated rmc. You need to buy the proper threading dies if you are using a "port-a-pony". It is a little harder to get the threads started, but you'll get used to it. Over all, it isn't much more difficult to thread than regular rmc. Make sure that you buy some pads, lead, or something to put between the conduit and the "teeth" of the vise, or the teeth of the "power threader" (if that is what you are going to use to thread with) so the the pvc coating doesn't get damaged. If you do damage it, you need to get some of the liquid pvc that is used to repair it. It comes in a can just like pvc cement that is used to glue pvc conduit. Even the straps, payne hangers, unistrut, ect should be pvc coated.
Man, you're gonna have fun on this job.
"As the squealing of a stuck swine; so shall be the voice of the "green aprentice" who humpeth the 4" pvc rigid."

In the spirit of Grasshopper,
Doc

Thanks for the witty and informing words. I have the pvc paint but was betting I would need special dies to thread for the portable threader. Will let you know how it turns out. Will make sure all my fittings and supports are pvc coated too.

OK, the threads are the same, you have to make certain that the throat fits OVER the conduit, or thou shall makest much damage. You cannot leave this damage unrepaired or geeez do you set up rust and corrosion very quickly. You'll get used to the smell and the noise

You'll have fun, fun, fun, till daddy takes the threader away. It's all over the water plant. You've got to cover all the cut threads anywhere they enter a box. They make these little sleeves and put some thread sealer on all the connections that you can't get a sleeve on. These guys that ran it out here, were slow, real slow, but if you ever nick it they might not take it. So all the bending and threding is lost. Out here they didn't even try to patch a rip or scratch. they just had to redo it. The utility wouldn't accept any repairs due to an accident in the treading or bending. The joints at the boxes are the most critical the cut threads will corrode the fastest. Good luck, I hope you come out OK.

Permacote, a conduit manufacturer, has a support page showing installation and threading tips, http://www.permacote.com/support/index.html.

Thanks everyone for your posts. The web site was very helpful Jbd. Thanks again