Circular tunnelling shield with removable bulkhead - has bulkhead in sections, and connected to internal flange and cross-beam

摘要

The circular tunnelling shield for tubes, tunnels etc., has a bulkhead across it, made up of an upper segment and a lower segment. The bulkhead can be removed and has a set of holes through it which can be closed. Inside the tubular skirt at the front is mounted a pressure ring, and across the inside is supported a T section cross member. The bulkhead is attached to the ring and cross member. The upper segment can be in two halves which swing inwards, attached to the vertical arm of the T section member. The attachments consist of wedges or threaded screws.