Rancho Seco Vessel Segmentation Decommissioning

S.A.Technology was contracted by the Sacramento Municipal Utility District (SMUD) to provide design, fabrication, assembly, testing, installation, training and maintenance support for supplying abrasive waterjet cutting equipment to be used in segmenting the Rancho Seco Reactor Vessel.

The design consists of a center-mounted square tube, centered inside the reactor, which supports a six degree-of-freedom manipulator with the capability to accurately position and rigidly hold a small waterjet cutting head during all cutting operations. The manipulator assembly consists of six axes; a vertical travel (Z-Axis) along the length of the upright center tube, a main rotational axis about the center of the upright tube (rotation of 540°), a Shoulder Pivot joint (rotation of 180°), a manipulator Forearm Extension (travel of 18 inches), a Wrist Rotate axis (rotation of 360°), and a Wrist Pivot axis (rotation of 180°). A post-cut cleanup end effecter suction tool was designed to remove excess abrasive and water from the reactor vessel pit after cutting is complete. This project was sucessfully completed on an accelerated project timeline.

S.A.Technology used advanced waterjet cutting technology to segment Rancho Secos’13” thick carbon steel vessel. All waterjet testing and demonstrations were done at S.A.Technologys’ facilities

• 55,000 psi ultra-high pressure pump with garnet injection supplies cutting nozzle;
• pump is electrically driven (100 hp) with a capacity of 6 gpm at 40,000 psi
• 
• Manipulator accurately positions and rigidly holds waterjet cutting head during
• cutting of up to 13” thick carbon steel vessel
• 
• Another end effecter allows the system operator to cut the 10” nozzles on the
• vessel using the manipulator’s built-in flexibility
• 
• Deployed from center-mounted beam, centered inside the reactor, with rotational
• motion controlled by a slew ring
• 
• A post-cut cleanup end effecter suction tool removes excess abrasive and water
• from the reactor vessel pit
• 
• The manipulator arm stores points in the current coordinate system using a
• teach mode (manually positioning the arm and storing that value) or by entering
• each coordinate using the touch screen
• 
• The waste water is transported to the waste processing skid, where the abrasive
• is separated from the clean water (using a cyclone separator) and packaged into
• 55-gallon drums
• 
• Two pan-tilt-zoom cameras are mounted on the arm to view the position of the
• joints for cutting head placement and during the cutting process; monitors on
• the control panels provide operator visibility of cutting operations

Equipment Overview

Full Scale Testing at S.A.Technology