The scope of this project was to develop and optimise the use of Ultra-High Pressure (UHP) Water Jetting as a method to access and safely vent pipework associated with the HAST 11 cooling coils capping and venting programme at Sellafield. Following on from this development work, Shepley Decontamination Services (SDS) carried out the hands-on manual decontamination of the floor box in which the HAST 11 pipework is located, before deploying the new UHP water jetting system to vent the pipework.
The SDS team designed a bespoke cutting head to clamp onto the HAST 11 pipework, which was accepted for manufacture and testing. The development was completed on a test rig built at the West Cumberland Engineering Workington facility. This rig was built after first taking onsite laser scans of the floor box and the creation of 3D models to ensure that the pipework represented the onsite conditions. The trialling work allowed for the proof of concept for the use of the designed UHP water jetting cutting head as well as the optimisation and development of the cutting and venting process. It was necessary to achieve CE marking for the cutting head tool, which was successfully accomplished.
The SDS team are still to perform spool cutting on the pipework – the cold cutting equipment for this task was optimised and improved during the trial phase. The team’s extensive experience with UHP Water Jetting and ability to identify and rectify issues allowed equipment to work as efficiently as possible.