Wear Mechanism and Strengthening Scheme of Core Components of Turnouts
Why are wear and failure of components more severe in the turnout area?
Wheels in the turnout area experience changes in direction, slippage, multi-point contact, and impact, with repeated alternation of lateral, longitudinal, and vertical forces. The stress on the switch rail, stock rail, frog, slide plate, top brace, and fasteners is extremely uneven. Structural space is limited, making elasticity and vibration damping design difficult. Once a geometric deviation occurs, the impact is amplified dramatically, creating a vicious cycle of "damage-impact-more severe damage."
What are the core components of a turnout that are prone to damage?
Switch rail, stock rail, frog, wing rail; slide plate, rollers, top brace, limit brace; elastic fasteners, insulating components, bolts, washers; switching equipment connectors, tight-fitting adjustment plates.
What are the forms of wear and damage to turnout rail components?
Switch rail side wear, switch rail tip crushing, spalling; stock rail web crushing, fastener wear; frog wing rail wear, burrs, chipping, corner breakage; wavy wear, contact fatigue cracks, rail end spalling.
What are the main technical measures for strengthening turnout components?
High-strength, wear-resistant rails are used, such as high-manganese steel frogs, alloy-reinforced frogs, and full-length hardened rails. The slide plates use wear-resistant, friction-reducing, and self-lubricating materials to reduce switch rail creep and wear. Reinforced fasteners, high-pressure spring clips, and high-load-bearing pads are used in the turnout area to improve stability. The fit and gap are optimized to reduce wheel-rail impact. Surface strengthening, weld repair, and pre-grinding are performed on key parts.
What are the core principles of turnout operation and maintenance?
Early inspection, early adjustment, and early repair to prevent minor defects from escalating. Ensure tight fit, uniform gap, and accurate geometric dimensions of the switch rails. Tighten bolts promptly and replace failed fasteners and insulation components. Regularly grind the turnout rails to eliminate corrugation, burrs, and peeling. Specialized management is implemented for small-radius curves, large-number turnouts, and heavy-load turnouts.