Horizontal tunnelling excavator - with a support shield and mixing chamber for mud fed from the digging buckets

摘要

The equipment digs horizontal tunnels has a forwardly manoeuvred shield (11) so that its head lies in the ground near the front of the bore. A mixing chamber (13) is formed by a partition (12) and the front of the shield is open over all of its front. A number of digging buckets (20) are at the front of the mixing chamber and have cutters (17,21,24) to excavate the earth. These are held on a support shaft (16) through the mixing chamber by rigid circumferential connections (23,26) between the buckets. There is a mud feed pipe (30) and several mixer blades (29).