Dnews write Hyundai E&C soon start to bore 5.3 kilometer tunnel under Panama tunnel for Panama Metro Line 3. Hynudai ordered a Tunnel Boring Machine 14 meters in diameter from Herrenknecht of Germany. It has arrived in Panama and ready to start tunneling.

In Korea, Hyundai use also TBM for tunnel under Han river. Top video. Again 14 meter in diameter for 2860 meter tunnel. Again Herrenknecht from Germany TBM brand. Dnews quote Hyundai manager say " “The TBM that penetrates the Han River Tunnel is a 'DCRM System', a 'Accessible cutter head' that can replace the cutter head under atmospheric pressure conditions and a temperature and wear sensor".

https://www.dnews.co.kr/uhtml/view.jsp?idxno=202309041711269250343

https://www.youtube.com/watch?v=6uXhWvIthWU