ClassID:

136018

E21D9/113 - CPC Classification

Classification description:

Tunnels or galleries, with or without linings; Methods or apparatus for making thereof ; Layout of tunnels or galleries; Making by using boring or cutting machines with a rotary drilling-head cutting simultaneously the whole cross-section, i.e. full-face machines by means of one single rotary head or of concentric rotary heads having a central part for making a pilot tunnel and a follow-up part for enlarging the pilot tunnel

Recent Application in this class: