Project Description: Background: Big Bend Dam is a major dam on the Missouri River in Central South Dakota, United States, creating Lake Sharpe. The Government intends to rehabilitate the Unit 6 servomotors, including cushioning valve system and optional work of chroming the servomotor rods, restoring the servomotor head fits, bore machining, piston head chrome, and piston head sleeves.
The scope of work for two servomotors addressed in this section includes: a. Servomotor removal: including rigging and handling equipment, removal of lower generator covers, disconnecting servomotor fasteners, provision of shipping cradle, and shipping, (leave wicket gates in full open position). The Government will provide a bridge crane operator to support a direct lift of servomotor to and from staging area withing the walls of the unit. Also loading of servomotors onto and off a truck and/or trailer. b. Wicket gate servomotor refurbishment: including inspection, replacement bushings, chevron packing, honing, cast iron rings, lead-based paint abatement and repainting. Optional cylinder bore clean-up cut. Optional rod chrome-built up. Optional piston rod chrome-built up. And optional piston spacers will be included. c. Replacement cushioning/dampening system shown on T7652F160, items 1-29, converted to equivalent new stainless swaglock fittings, piping, unions, gauges, and joint connections. d. Installation of the servomotors: including reconnecting any pipes, fasteners, pins, and any needed adjustment to ensure proper connection to the operating ring.
