The WREN multi-stage bolt tensioner adopts a miniaturized design, greatly enhancing operability in narrow working spaces. The integrated spring-loaded mechanism allows for automatic socket-to-nut alignment, effectively reducing operational complexity. WREN can customize various types of hydraulic bolt tensioners according to the different application requirements of extra-large equipment in industries such as chemical engineering, wind power, nuclear power, aerospace, and heavy machinery. WREN offers personalized customization based on performance indicators including tensile force, adjustment accuracy, and data recording.