With the development of electronic technology, computer technology has become an indispensable tool in all walks of life. In the design industry, the application of computers in engineering design and management has gradually become one of the indicators for measuring the level of engineering design. Despite more than a decade of exploration and development, domestic design units have not yet made significant breakthroughs in the overall level of application. With the rapid development of hardware technology, in recent years, some internationally renowned software companies have gradually developed and improved a number of 3D integrated design systems that can be applied to plant design. These design systems break through the traditional concept of drawing design on a two-dimensional plane, transforming engineering design into the practice of building a physical model of the plant in a true three-dimensional electronic space. Due to their many advantages, these Plant Design Systems (PDS) have been widely used by some large engineering and consulting companies in the West. Some well-known international equipment supply groups (such as Siemens, Mitsubishi, and ALSTOM) and some large engineering companies have equipped themselves with advanced 3D plant design systems in recent years. In my country, some design units in the petrochemical industry have also taken the lead in adopting this design technology and have successfully applied it to domestic design engineering projects. In the process of my country's design industry becoming increasingly market-oriented, power design is no exception. Only by quickly aligning with international standards and reaching or catching up with advanced international design technologies can we maximize our overall competitiveness. For mechanical engineering, the widespread application of advanced 3D design technology to improve the technical content of designs, save project investment, and unify standardized designs has become one of the ways to improve design technology. Currently, there are many 3D design systems with relatively complete functions in the world. INTERGRAPH's PDS is one of the best. It can simulate factory facilities in a computer and, by integrating and utilizing various software modules, realize the functions of building engineering models, preliminary design, construction drawing design, and design review. Moreover, because its reference database is standardized and open, it is easy to develop and maintain the database in accordance with the standards of various countries. PDS has been adopted by many international engineering companies. In design cooperation with the French company ALSTOM, the design management program of the foreign company was adopted, and the American PDS software and workstation were used to complete the 3D model design of the conventional island of the Ling'ao Nuclear Power Plant. [b]1 Main Functions of PDS[/b] PDS is powerful and can meet the requirements of 2D and 3D design. The 2D design function is mainly used to create piping system flow diagrams and piping instrumentation diagrams, and to extract relevant report lists and bills of materials. Because the 2D function can input data into the subsequent detailed piping design, it ensures consistency between the flow diagram design and the piping layout. The 3D design function is the core of the entire system and the most important component in realizing its engineering design. This part mainly has functions such as creating a 3D electronic model of the plant, extracting piping construction drawings (isometric drawing), generating various plant layout drawings, and performing design clash checks. The main modules of PDS 3D design include equipment model module, steel structure module, piping design module, reference database management module, graphics management module, PDS stress analysis interface, clash check-management module, piping isometric drawing interface, report generation module, and design review module. 2 Application of PDS 3D Design Technology in Nuclear Power Plant Design Unlike conventional mechanical design, 3D design technology is a completely new design technology, requiring the use of a large PDS and a drastically different design management method. To this end, in the design project of Ling'ao Nuclear Power Plant, Guangdong Electric Power Design Institute established a factory model including more than 30 equipment model files, more than 20 pipeline model files, 7 steel structure model files and 8 concrete structure model files, solved all collisions within the work scope, and generated a batch of construction documents including pipeline isometric drawings (157 sheets), plan and section layout drawings (14 sheets), and support and hanger installation drawings (758 sheets), which passed the final acceptance of the foreign party. [b]3 Benefits of PDS 3D Design Technology[/b] 3.1 Updated Design Concepts 3.1.1 Concise and Visual Design Method The use of 3D model technology changes the original design of arranging factory equipment and facilities on flat drawings to "building" a real factory in a virtual 3D space. PDS comprehensively integrates various disciplines of factory design. The system allows designers to simulate various parts of the factory in 3D space, including: civil engineering of the plant, steel structure, ladders and escalators, cable channels, electrical panels, HVAC equipment, heat exchangers and pumps, pipelines, pipeline supports and hangers, and other equipment and facilities. It provides users with a complete electronic simulation factory throughout the entire design process. It can be continuously updated according to user requirements and, through connections with material and engineering databases, controls design modifications and changes throughout the power plant's lifespan. 3.1.2 Collision-Free Plant Design In traditional design practice, due to ineffective communication between designers from different disciplines and sub-sections, and the limitations of two-dimensional design space, the construction drawings submitted by the design unit inevitably experience various collisions during on-site construction, sometimes significantly impacting the schedule and costs. PDS's three-dimensional design system allows users to perform collision checks using modules in a shared three-dimensional space, making the designed factory a truly "collision-free" factory. This is significant for reducing engineering construction costs and shortening the construction period. 3.1.3 Automatic Generation of Piping Construction Documents In traditional design processes, the design of piping construction documents accounts for the vast majority of the workload for mechanical engineering professionals. For example, for a 300 MW power plant, the mechanical engineering professionals generate thousands of piping construction documents, consuming approximately 6,000 design working days. Using PDS 3D design, after model creation, it can automatically generate pipeline construction documents such as plan layout drawings, pipe isometric drawings, material reports, and material summary tables, saving design workload. The drawings are accurate, standardized, and aesthetically pleasing, which helps reduce construction errors and saves manpower and resources. 3.1.4 Unified and Standardized Design Because the pipeline model must be consistent with the specifications of the pipelines in the reference database, the project manager can define the contents of the reference database to limit the specifications of pipe fittings to be used in the design before starting the engineering design. For a project, unifying the design standards of the project through the reference database has many advantages. It allows project managers to effectively control the types and specifications of materials selected for the entire project based on changes in the material market; it also standardizes the categories of materials to be purchased, reduces the workload of procurement personnel, and has a positive effect on reducing procurement prices. 3.1.5 Optimized Design and Reduced Design Errors The 3D design system has a full set of CAD functions from preliminary design to detailed design, and from 2D to 3D. It allows designers to directly input relevant data from the scheme design into the detailed design, and controls the design input data through a database. This greatly reduces the amount of data input and aggregation required by designers during project execution, significantly reducing the possibility of human factors affecting the quality of the final engineering design. Furthermore, since all modules operate within a single system, the possibility of conflicting information in the design documents is reduced. 3.1.6 Provides a foundation for material management. For a large-scale engineering project, design, material procurement, on-site material management, and construction are inseparable. Using PDS for engineering project design allows for the organic management and control of these aspects. 3.2 Adapting to the market economy and aligning with international standards. 3.2.1 A powerful tool in power engineering bidding. In the current domestic market that is gradually standardizing and encouraging competition, design units inevitably face the situation of entering the market and participating in engineering bidding competitions. Providing high-quality service at reasonable prices is the principle and the foundation of their survival. Adopting 3D factory design technology and aligning with international standards is the only way to improve design levels and enhance competitiveness. 3.2.2 Expanding Design Scope: A Prerequisite for Subcontracting to International Companies The current international power market is largely dominated by a few powerful international companies. my country's low labor costs present a potential growth opportunity, making cooperation with foreign engineering companies, subcontracting, and participating in design projects a new development direction for design units. As previously mentioned, international suppliers now employ 3D design technology, making 3D design capability a prerequisite for participating in projects contracted by international companies. 3.3 High Technology Leads to a Revolution in Power Design 3.3.1 Database Management A 3D system is a comprehensive and large-scale design system. In terms of software application, mastering its usage techniques and applying them to engineering practice is essential for carrying out design projects. Managing and applying the database is crucial for utilizing this design technology. The PDS system contains three main databases: a reference database, an engineering database, and a design database. These three databases centralize the sources and conclusions of engineering projects and form the heart of the entire PDS. Since pipeline model design is closely related to the reference database, the reference database is a vital source for pipeline design among these three databases. Before commencing a design project, the design standards and requirements to be used must first be determined. Users need to modify or update the reference database to fill in the relevant parameters of the required pipeline design standards; this process is called "customization." Through nearly ten years of exploration and development, domestic power design units have done a great deal of preparatory work in using domestic design standards for CAD design, and are fully capable of "localizing" the PDS reference database. 3.3.2 Network Management The establishment of a factory model often requires the collaboration of a dozen or even dozens of people. 3D design requires designers to work together on a computer network. How to manage the work permissions of workers on the network and ensure that everyone works securely and independently while maintaining mutual contact is also a key aspect of using 3D design technology. We believe that user-friendly management and data resource backup management of computer networks are very important. 3.3.3 Program Management The 3D design system breaks the current design management model of design units based on "sections." In terms of design management, PDS also has very distinct characteristics, mainly reflected in the control of the design process and the control of design conclusions. Process control refers to using strict design management procedures to control every step of model making. 3D model design is like building an engineering project in electronic space, a collective effort involving many designers. During each model creation process, input information must be recorded and jointly confirmed by the designer and checker. When using collision detection to check the model, opinions and modification information for each collision point must be recorded according to the collision detection report. For design modifications, the modification information and its source must be recorded on the original design document. With various control measures, the correctness of the model input and the traceability of the design scheme can be largely ensured. Control of design conclusions refers to the review and approval process for the final design. The final 3D model design is generally extracted all at once after the model input work is completed and the design check is finished. Although the model has been checked by the model checker after input, some parameters and information related to construction are directly related to pipeline construction and ordering. Therefore, these final products must still be strictly checked according to the verification procedure to ensure their correctness. [b]4 Popularization of PDS 3D Plant Design Technology[/b] The main advantages of 3D model design are: establishing dynamic power plant models; conducting collision checks; automatically generating design drawings and statistical tables; and providing a complete set of electronic files. Large international engineering companies have applied 3D design technology to almost all large-scale industrial projects. In my country, the use of computer-aided 3D model design for large power plant projects with a single unit capacity of over 300 MW is also a trend in power construction. Utilizing 3D design systems can fundamentally improve the design technology level of mechanical engineering and even the entire power design project, providing users with modern, high-quality design products, as well as a set of "electronic 3D management tools" that can track the entire power plant process. This provides advanced means for power plants to review design schemes, control design quality, control material procurement, and control investment costs. It also represents a creative advancement in providing favorable methods for expanding the power industry's MIS management system into the production field, with significant economic and social benefits. With the further improvement of the national economic situation, power construction will face more opportunities, which gives power designers confidence in the widespread application of 3D design technology in power engineering.