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Department of Transportation - Division of Maintenance Structure Maintenance & Investigations MECHANICAL/ELECTRICAL ELEMENT INSPECTION RATINGS AND NOTES Elem Defect/ Element Description No. Prot Defect Env Total Units Qty CS 1 9003 Alignment (Mechanical) 2 1 ea Qty in each Condition State CS 2 CS 3 CS 4 (601) Support System - Mechanical Non -Routine Inspection Element Notes: The mechanical support system consists of four components: Center Pivot Bearing, End Wedges, Centering Pins, and the Center Wedges. The center bearing consists of a pivot base casting, upper pivot casting, upper bearing disc, lower bearing disc, and retainer ring. All the weight of the swing span is supported by the center bearing during operation. There are two end wedges with live load shoes at each end of the swing span to support the bridge for traffic. Each set of wedges is driven by the gasoline engine. The wedges are pulled and driven via a series of gears, shafts, and cam linkages. Each centering pin is moved vertically in a guide system by a lever and cable mechanism located in the operators house. The latches are counterweighted and return to the down (engaged) position manually by the operator. Both centering latch systems functioned normally during the inspection. Center wedges are located at the center pier and are driven by the gasoline engine. The wedges are pulled and driven via a series of gears, shafts, and cam linkages. (601-9003) Alignment (Mechanical) Non -Routine Inspection Element Notes: (06/03/2021) All four end wedges have mis-adjusted cranks and connecting rods resulting in poor clearance of the wedges when fully retracted. The south east wedge is rubbing against the wedge seat mounting bolts. The two center wedges have mis-adjusted cranks and connecting rods resulting in poor clearance of the wedges when fully retracted. ** Update (05/10/23) Condition still present. (05/10/23) The end jack gearbox at the center pier has a leaking seal. Could not remove drain plug at the time of inspection to verify fluid level. (05/10/23) The east wedge drive shaft coupling is misaligned causing the coupler to pinch at the top and open at the bottom during rotation. The output shaft from the gear reducer and it mating shaft need to be realigned. (05/10/23) The southeast wedge rubs on the north east seat during operation. (05/02/25) Condition still present 602 Balance System - Structural ea (602) Balance System - Structural Non -Routine Inspection Element Notes: The balance system consists of center pivot pier the balance wheels and track assemblies. No structural defects were observed. 603 Balance System - Mechanical 9002 Wear(Electrical) ea ea (603) Balance System - Mechanical Non -Routine Inspection Element Notes: (06/03/2021) Balance system consists of six balance wheels (AASHTO a minimum of 8 in current design standards), and track on the pivot pier. (603-9002) Wear(Electrical) Non -Routine Inspection Element Notes: (06/03/2021) The mounting plate below the track assembly is bent and deformed throughout the full length of the track. There appears to be pack rust and grout failure under the track mounting plate. This condition has possibly resulted in an untrue balance wheel rail height. The balance wheel track mounting plate should be replaced and the track releveled. **Update (05/10/23) Condition still present (05/02/25) Condition still present 604 Drive System - Mechanical 9002 Wear(Electrical) (604) Drive System - Mechanical ea ea Non -Routine Inspection Element Notes: Mech/Elect (06/03/2021) The bridge mechanical drive machinery consists of a single gear drive system. Power to the system is provided by a V8 internal combustion engine. Power is transmitted to the turning machinery gearing through a lever operated clutch system that has two positions, forward and reverse. When the clutch is engaged, a bevel gear and pinion set transmit torque from the engine output shaft to the turning machinery. Additionally, there is one more set of bevel gears, three sets of spur gears, and one main drive pinion mating up to the rack gear. The rack is fixed to the pivot pier structure. As the main drive pinion turns about the ring gear, the swing span is opened. All four end wedges and both center wedges are actuated by a common gear and shaft system that connects to the gasoline engine by a lever operated clutch. At the end of the drive lines, each wedge has a crank shaft and connecting rod. Rotation of the wedge crank shafts withdraw or engage the end and center wedges. All four end wedges and the two center wedges engage steel support pedestals fixed to the end and center piers. The end centering pins Printed on: Friday 05/30/2025 01:32 PM Page 6 of 8 29CO219/AABI/153159