It was made by Hitachi Zosen Sakai Works in Osaka, Japan, and the machine's assembly was completed in Seattle in June 2013. Tunnel boring began on July 30, 2013, with the machine originally scheduled to complete the tunnel in December 2015.OverviewBertha was a 57.5-foot-diameter (17.5 m) built specifically for the 's (WSDOT) project in ,. .
The name Bertha, after Seattle's first female mayor, , was chosen by a panel (that included the Governor and Transportation Secretary) from 150 submissions from kindergarten through 12t.
[pdf] The Speedstar SS-25 SP Rig has been extremely well maintained deep water well drilling rig. It has 22” clearance through the table and a brand new Failing 75 ton double roller bearing rotary table. The Sp.
[pdf] It is a fully integrated, multiple module unit that can drill on ten-foot well spacing. The rig layout consists of six individual modules, resulting in lightweight components that can be efficiently moved from p.
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