Sellafield SIXEP Tank Optptimization Project
| Client | British Nuclear Group/RTS Nuclear |
| Facility | Sellafield |
| Location | Seascale, Cumbria |
S.A.Robotics provided a Pipe Cropping Manipulator (PCM) to remotely cut riser pipes inside two 1000 m3 Bulk Storage Tanks (BSTs) in the British Nuclear Group’s Sellafield Ion eXchange Effluent Processing (SIXEP) facility. The PCM included a telescoping mast, Ultra High Pressure (UHP) Cutting Heads, pneumatic supply, video capability, simple joystick control panel and associated software.
The BSTs are used to settle out and store magnox sludge and their capacity was limited by increasing sludge levels. The PCM remotely cropped the lower section of five decant pipes within each BST, thereby successfully increasing their effective storage capacity.
Features:
- Telescoping mast included three carbon fiber tubes with two hydraulic cylinders
- Telescoping arm had horizontal reach of 20 feet
- The vertical motion of the mast was recoverable by the use of a powered auxiliary winch
- The tubes were supported with Ultra High Molecular Weight Polyethylene sliders
- A pipe gripping jaw and a compliance joint, called the tool yaw, provided flexibility to ensure that the cutting heads did not overload the pipe or arm during cutting operations
- The mast was rotated via a mast rotate and slew ring assembly. Additionally, a 90 degree shoulder joint and bicep extension features allowed all pipes to be accessed and cut while avoiding obstructions
- The cutting head consisted of two abrasive water jet cutting heads attached to a slider mechanism; each cropping head carried two water jet cutting nozzles fed by water and garnet providing both cuts simultaneously
- The PCM was withdrawn through a wash down spray ring for decontamination before being moved between the two BSTs
- Electrical components installed within the tanks were explosion-proof rated for a potential hydrogen environment
- The Ultra High Pressure water Intensifier, Abrasive Feeder Unit, and hydraulic power pack for arm/mast operations were mounted on separate skids
- High pressure piping and tubing was routed via the PCM mast and along the top of the manipulator bicep to the cropping head
- The PCM was operator controlled with easy joystick and touch screen Human Machine Interface controls. A programmable logic controller handled all interlock and precision motion controls
- A full-scale test rig was used to fully replicate the site deployment constraints and for training operators for all PCM remote operations
- The PCM was designed so that it can be decommissioned and removed via the designated entrance route using a preplanned rigging operation
- All engineering, procurement and fabrication were conducted under S.A.Robotics’ ISO 9001 QA Program and the PCM is CE Marked