I just went thru the code book to find out where expansion joints are required on steel conduit. My conclusion is that they are not.

Is that correct?

Now if it is correct, I am still going to need to buy some. On my facility there is a 1,000 ft plus conduit run of 2 inch IMC exposed outdoors. Theres J boxes about every 400 feet. At some j boxes the conduit has shrunk and pulled out by 3-4 inches.

Doing the math in the code book for expansion of steel conduit I get 3/4 of an inch for 100 feet for 100 degree F change. So a 400 foot run will be 3 inches. Enough to cause problems.

Right now I am thinking of ordering enough of those things to install at each jbox.

Good or bad idea?

Thanks.