If i upload image and save node - image saved to cck field.
If i upload and insert image to body - image don't saved to cck field.
Insert module does not modify the way FileField saves the files in any way. Insert module actually affects nothing based on whether you've inserted the file or not, it's merely a JS tool that generates the links and inserts them into the body field for you. If having the image in the body field makes it so that the file isn't saved properly, you would probably see the same behavior if you manually made the link in the body field instead of using Insert module. Though I can't see why this would be happening, I think it's very unlikely that Insert module is the source of the problem based on your description.
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