Boolean/Trim/Split/Intersection Problem

I need to remove the portion of the orange ring which is outside of the green ring in the attached file. Nothing seems to work. Intersection finds only a small portion of the intersection between them. The rings are bodies of revolution, and both are copies of the same original.

What is going on?

Rings Question DC.3dm (752.1 KB)

Rings Question DC.3dm (1.3 MB)

Can’t do English sorry

The problem is simple.

One side only slightly greater than or less than or equal to.

I do not know well to be passed to the translator.

Thank you for the response. The rings are exactly the same size.

I found a solution

The original ring was created using Revolve, and the profile curve was a closed polycurve with sharp corners. The result was a single surface with creases. It appears that BooleanSplit, Split, Trim, Intersect, etc. do not work properly with two creased surfaces.

I used DivideAlongCreases to convert the creased surfaces with rings to polysurfaces.

Everything appears to work properly with the polysurfaces.