Seoul Metro Line 9 Extension
South Korea, Seoul
2016 – 2017

The Seoul metro has been running through the South Korean capital since 1974 already. Today the metro network consists of nine lines and is constantly being expanded for the ever-growing city.

High-tech from Schwanau was used to extend Line 9: a 7,700 mm diameter EPB Shield excavated two 372 m long tunnel sections for the new metro route. Tunnelling began in April 2016. In May 2017, the site crew successfully completed work on the tunnel shell. The new section has been in operation since December 2018.

Data Sheet

Country, Location

South Korea, Seoul


2016 – 2017




Heterogeneous ground:
Schist, alluvium soil, silt, sand, gravel

Tunnelling length

744 m

Machine Data

1x EPB Shield
Diameter: 7,700 mm
Lining method: Segmental lining
Cutterhead power: 2,000 kW
Torque: : 10,366 kNm

Your contact person Contact us

Steffen Dubé President and General Manager Herrenknecht Tunnelling Systems USA Inc.
Gerhard Goisser Commercial Manager Herrenknecht Tunnelling Systems USA, Inc.