This paper studies the digital design and operation and maintenance model for nuclear safety-class DCS for the operation end. Traditional design delivery methods rely on paper drawings, which suffer from issues such as scattered information and low query efficiency. The digital design and operation and maintenance model integrates data throughout the entire engineering design cycle, constructs structured and interactive digital assets, and achieves efficient management and seamless information transmission. The paper proposes key technologies such as digital impact analysis, material component positioning, dynamic visualization of signal chain, and visual design of cable lists, including attribute digitization, dynamic path generation, 3D spatial data integration, dynamic signal chain visualization, and structured management of cable lists. This model can improve operation and maintenance efficiency and work quality, and is applicable to DCS in the nuclear industry and other industries, providing an effective means for “what you see is what you get” operation decision support.