Design and automation of CAREM25's steam generators blind flange removal and manipulation machine

CAREM25 project presents innovative features in its design and hence many of the devices used in its operation won't be standard products. The heat exchange interface between primary and secondary water, is located within the reactor pressure vessel (RPV), where twelve steam generators (SG) are located. Assessing the structural integrity of each SG pipe is mandatory in order to prevent perforations that would lead to contamination of secondary water from primary circuit. To perform inspection and maintenance of SGs, there are several tools being developed by CNEA to create an automated system which employs an industrial robot and a large number of inspection, support and positioning devices. Among them, there are some large-sized equipment such as a rail transport subsystem and a special machine for blind flange removal. These flanges weight around 600 kg, so they can't be manipulated by the actual robot. This task requires a robust automated device that works in conjunction with the robot. It must be able to support the flange's weight, and also to handle, remove, transport and return them to its final position. In this work conceptual engineering of the flange removal machine is presented, justifying the selection of actuator devices, structure, positioning and guidance systems. Additional specific support structures for this design are mentioned. The machine utilizes the rail system used by the robot with the ability to rotate itself, move linearly and perform all the movements required to position itself below the flange, remove, manipulate and transport it. This design comes from Mechanics, Materials and Non Destructive Analysis Department in cooperation with Robotics and permanent feedback from Piping and Civil Engineering areas in order to achieve fast monitoring of the design process and avoid interferences. (author)