Shield tunneling requires reliable real-time measurement in dusty, wet, and vibration-heavy conditions. A flange-mounted linear displacement sensor is designed for this environment. Its flange simplifies rigid installation on shield jacks, segment erectors, and gate actuators, while the linear sensing element delivers continuous stroke feedback for tunnel boring machine control. Accurate displacement data helps operators monitor jack extension, synchronize thrust, and support precise segment erection. The sensor housing usually offers high IP protection, shock resistance, and electromagnetic compatibility to withstand slurry, grease, and strong interference. Common outputs include 4-20 mA, 0-10 V, RS485, and CAN, enabling easy integration with PLC and SCADA systems. For harsh shield tunneling sites, engineers should specify the correct measuring range, resolution, cable outlet, and protection class. A well-sealed flange interface prevents water and grout ingress, while shielded cabling minimizes signal noise. Regular inspection and simple zero-point calibration keep displacement readings stable throughout long drives. This improves uptime and data reliability while reducing maintenance costs. During shield tunneling, stable flange mounting reduces misalignment and cable stress, improving service life and maintenance efficiency. With rugged construction and real-time feedback, the flange-mounted linear displacement sensor supports safer excavation, better alignment, and higher tunneling productivity.