The Shield Tunneling machine rubber seal is to escape the drilling solids and water come into the machine. Like the following photo show.

Parameters:
Material: NBR Rubber
Inner support: 2 layers of wire support, cotton wire and nylon wire
Out diameter and inner diameter: are determined as per tunneling
Edge: outside edge has water drop type to protect better seal
Remarks: small size are non joint rubber. 

Welcome to contact with us about rubber seal for your tunneling projects.
Email: alisa@jxsolidscontrol.com