We apply advanced integrated CAE system to our business segments, including construction and maintenance of nuclear power plants and fuel cycle facilities. We continuously improve our design, construction plan, maintenance service and management of quality control by using the system with integrated engineering databases such as 3D plant design information, drawings, work progress and record of installation, maintenance and inspection services throughout the lifecycle of the plants.
We use point cloud data acquired through a laser-based measurement method in the construction and maintenance operations of nuclear power plants. These data are used mainly for the implementation of on-site dimensional measurement to install new piping routes, the construction of 3D-CAD models and the production of installation drawings. Reducing man-hours for the construction of 3D-CAD models from point cloud data is a major issue. To address this, we developed two types of tools to eliminate the manual visual inspection process when constructing as-built 3D-CAD models from point cloud data and bottlenecks that occur in the creation of models.
(1) We developed a 3D-CAD and point cloud data verification tool that checks 3D-CAD and point cloud data and classifies results into different categories, including those showing the matching of 3D-CAD and the point cloud data, and differences in the shape and position. The tool classifies these results based on distances and deviations from 3D-CAD model-based parts after applying an iterative closest point (ICP) algorithm.
(2) We developed basic functions (loading of point cloud data, realignment of positions, walk-around, picking of point clouds, dimensional measurement, display/hide, entry of models, etc.), which enable designers to load point cloud data in the 3D-CAD developed in-house and directly construct as-built 3D-CAD models and carry out relevant operations while simultaneously referring to these point clouds data.
We continuously improve our construction management using Construction Coordination System linked to 3D design information.
We manage construction planning, installation work and the record data efficiently with leveraging our Construction Coordination System. In the planning phase, we can examine an installation process efficiently based on the established linkage between an installation procedure and information on the amount of materials. In the installation phase, we can refer digitized instruction information and input a record in the work field and handle a large amount of installation operations efficiently. In addition, we can access installation schedules, progress and measurement records and use the information for the analysis and evaluation of the construction plans.
Our on-site offices are introducing ICT technologies to increase the number of information transmission and reception points and ensure that construction operations are conducted efficiently. We set many large information monitors to display daily safety notices and cast morning assemblies to separate locations in construction site to hold with remote workers. In addition, workers can access construction related information, such as schedules, progress of construction and on-site training content.
More than 1,000 operators engage in their assignments every day at a nuclear power plant keeping safety first in mind. We have training programs using virtual technology-based teaching materials to ensure that each operator can prevent the occurrence of industrial accidents. Trainees can simulate accidents, feel fear, consider errors that occurred in the past as relevant to them, and acquire knowledge about accidents prevention, while increasing sensitivity to danger. Through efforts for safety management enhancement, we aim to achieve zero industrial accidents at nuclear power plants.
We have efficient training program for improving installation quality and prevent from human error through the introduction of the latest VR technology in addition to OJT and lecture classroom. We established piping models and scaffold models in simulated plant facilities and use them for training to improve installation quality. Trainees walk in and look at virtual spaces similar to actual sites to check errors prepared in the models. This training enables operators to gain skills in finding installation errors irrespective of work experience efficiently.
We adopt the large module-based construction method to reduce the construction period. We assemble modules included equipment, pipes, valves and steel structures in advance and set it into the plant during construction. Modules are established based on highly advanced engineering and multiple evaluations with respect to a broad range of items including their balance, structure stability and installability. Some of these modules weigh more than 600 tons.
We use a large crawler crane to implement the method. The new crane, which has a lifting capacity of 1,200 tons, can set very heavy and large modules. In addition, it can hoist products and move them more broadly than conventional model. We can set an enormous number of parts which constitute the nuclear power plant by the crane efficiently.
