Railway Turnout Assembly Installation Specifications And Operation Guide

Railway turnouts are critical components of the track system, and their installation quality directly impacts the safety and stability of train operations. This article details the standardized installation process for turnout assemblies, providing a professional reference for engineering and technical personnel.
During the preliminary preparation phase, the integrity of all components, including the stock rail, point rail, switch, connecting rod, and fasteners, must be rigorously inspected, and the design drawings verified. Before installation, the trackbed foundation must be measured for flatness to ensure that the sleeper spacing error does not exceed ±2mm. A hydraulic track lifter should be used to adjust the levelness of the reference rail to within 1‰.
The core installation process consists of three steps: First, the stock rail is positioned, the longitudinal position is calibrated using a laser rangefinder, and the sleeper connection is secured with high-strength bolts. Next, the point rail assembly is installed, ensuring a contact fit of ≤0.5mm with the stock rail. The opening is adjusted by adjusting the wedge. Finally, the switch mechanism is assembled, and the linkage accuracy of the operating rod and indicator rod is simultaneously tested. The switching force is required to be within the range of 4-6kN.

Key quality control points include: ① Insulation joint resistance ≥ 10Ω ② Slide bed oil coating thickness maintained at 0.2-0.3mm ③ Strict torque requirements for all fasteners (e.g., M24 bolts must be 300-350N·m). After installation, at least three back-and-forth switching tests must be conducted, and full-section geometry must be checked using a track gauge.

Construction teams are advised to adhere to a "three inspections and three verifications" system (self-inspection, mutual inspection, and specialized inspection; acceptance by the work team, acceptance by the project department, and final inspection by the supervisor) to ensure that each turnout installation complies with the TB/T 412-2014 industry standard. Standardized installation procedures can effectively extend the turnout's service life to over 15 years, providing a solid foundation for railway transportation safety.