The industrial Internet platform has garnered significant attention from both academia and industry due to its potential to enable the operation of digital value chains in manufacturing firms. However, the existing research has not yet fully explored the “black box” of how the platform enables the operation of digital value chains in manufacturing firms. Focusing on Haier COSMOPlat and the manufacturing firms it enables, this paper uses a case study approach to investigate the mechanisms through which the industrial Internet platform enables the operation of digital value chains. The findings reveal that the industrial Internet platform enables manufacturing firms to realize digital twin value-chain elements, digital-driven value-chain structures, and digital enhanced value-chain relationships, thus supporting the overall operation of digital value chains. Through a comparative analysis of the structure and scope of digital value chains, it is concluded that the industrial Internet platform enables the reconfiguration of value chains in four key ways: value-chain strengthening, value-chain expansion, value-chain upgrading, and value-chain renewal. Digital value chains have undergone innovative changes compared to traditional value chains in terms of dominant logic, core resources, activity stakeholders, network relationships, and target effectiveness. This paper offers practical insights for accelerating the development of the industrial Internet platform and helping manufacturing firms build digital value chains to achieve high-quality development.