ProEn’s customer commissioned the analysis and drawings for three 160 ton trolleys, gantry structure, gantry drives including equalizing trucks to allow synchronized lifts of three gates at a hydroelectric dam.
This unique lift system integrates four different types of cranes working together as well as an auxiliary cantilevered service crane. The design parameters called for the ability to raise and lower one to three of the dam’s gates, with a particular requirement to effect rapid emergency shutdown of a single turbine to prevent damage.
Development included proofs for 26 different load cases including seismic forces and variances in wind loads at the top and bottom of the dam. Among ProEn’s design features were jacking points in the sills for changing out trucks and bearings, and complete detail work for cranes, structural columns, catwalks and walkways. Although the customer initially estimated maximum dead loads in excess of 2.5 million lbs., ProEn’s design met all requirements with total dead weight under 2 million lbs.