Population Change and Public Policy Concept Paper for a SSHRC Strategic Research Cluster

A primary device placed at the upstream end of a duct and a relay device placed at an access point pull a cable through respective duct segments. The pulling speed of the primary device is controlled by an operator. The pulling speed of the relay device is variable in response to movement of the cable by the primary device to maintain equilibrium between the pulling speeds of the devices. The pulling tension exerted upon the cable by each device is monitored and discontinued upon reaching a predetermined maximum value. At the inlet to the second segment, lubricant is supplied to the cable at a quantitative rate which is proportional to the pulling speed.