It's true. There are some more in-depth details (with graphics and PDFs) here: http://www.canmakers.co.uk/education
"13.An interlocking seam is formed at high speed. Up to 2000 cans go through the process each minute."
http://www.canmakers.co.uk/wordpress/wp-content/uploads/2011...
Also tried a site-wide search: https://www.google.com/search?q=site%3Awww.canmakers.co.uk+w...