Washington State Ferry System

Washington State Ferries is the largest ferry system in the United States, serving eight counties within Washington and the Province of British Columbia in Canada. The existing system consists of 10 routes and 20 terminals served by 29 vessels, and it's an essential part of Western Washington's highway network - carrying over 11 million vehicles and 26 million people per year. As part of a safety upgrade to state ferry terminals, WSF engineers wanted to install line tension monitors to the heavily used auto and passenger transfer spans that connect vessel and terminal.

Rugged Controls developed a dedicated line monitoring system consisting of a modified LCI-100 dual-tension display, one 7,000 pound or two 10,500 pound tension links, and interconnect cables. The LCI-100 interfaces with the current output of the tension links, and provides a visual display of line tension along with the added safety of high/low tension alarm setpoints. This system was designed to be fully autonomous, and it requires only annual calibration checks and visual inspection to ensure continued trouble-free performance.  Rugged Controls worked with WSF engineers and terminal operators to determine how best to maintain enough tension on the winch line when the winch was shutdown.  It was determined that by using a low tension alarm from the LCI-100, that enough tension could be maintained on the line in order to facilitate proper spooling and prevent damage to the wire rope. 

Rugged Controls also provided destructive testing services on all tension links used on the ferry terminals.  All tension links were found to have in excess of a 7X safety factor.