Originally Posted by antiteam
I hadn't thought about that aspect. I'm not sure I'd worry as much about it fitting inside (it's gotta all fit through the 1" hole in the end, right?) but any sort of flexing might lead to it touching the outside of the tube.
If the element touches the outside of the tube, is that an instant short (assuming a conductive tube, of course)? I don't have much experience with these elements. I'd think the answer would be yes if they're not electrically insulated in some manner.
The threaded hole for a 1" pipe thread is about 1.141" at minimum, so the element has to be less than 1 1/8" in diameter. The OD of 1" pipe is 1.315", and the wall thickness is .133 for standard pipe, so the ID is actually 1.049".
From experience I know that a low watt density element will contact the side of a 1" pipe (tried it in the hardware store with an element and a 1" pipe).
The outside of an undamaged element is isolated from the current carrying wire, so touching the pipe will not cause any electrical problem, however it might cause a hot spot on the element leading to a burn thru. Also, any significant bending of an element to get it directly in line with the center line of the threads might weaken the element wall and crack the insulating material surrounding the element.