The standard positive line contact rail is mounted on insulated brackets spaced between 3 to 5 meters apart, with a tolerance of ±10mm for bracket positioning. In special areas such as stations, transitions, bends, ramps, or expansion joints, the minimum distance between brackets must be at least 3 meters to maintain stability and prevent electrical disruptions.

For connecting adjacent rails, common connectors are used to ensure a secure and reliable electrical connection. These connectors feature tight tolerances to minimize movement between the rails, maintaining alignment and reducing wear. The joint surfaces must be perfectly flush to avoid any unevenness or twisting, with an installation accuracy of 0.5mm. This ensures smooth operation and consistent contact between the train’s pantograph and the rail.

The expansion joint is designed to accommodate thermal expansion and contraction caused by temperature changes, current-induced heating, sunlight exposure, and mechanical movement. It is aligned with the contact surface of adjacent rails to allow the train’s electric shoes to pass without interruption. The expansion joint measures 1975mm in length and should be placed centrally between two support brackets in straight sections. A minimum clearance of 400mm must be maintained between each end of the expansion joint and the nearest bracket. In curved sections, the increased tension can cause premature wear on the sliding block and insulating brackets, so expansion joints are typically avoided at bends unless the radius is larger than 300m.

When expansion joints are required at smaller-radius curves, the tension is transferred through the anchor points, which must be carefully managed to prevent damage. Additionally, intermediate connectors are used to link external power sources to the contact rails, allowing 8 to 12 wires of 240mm² cross-section to be connected. These connections must be made with sufficient slack to prevent additional stress on the rail, preserving its ability to move freely under thermal conditions.

At the ends of the trolley lines, two types of elbows are used depending on whether it's a mainline or yard line. The mainline elbow is 5.2 meters long with a height difference of 126mm between the two ends, while the yard elbow is shorter at 3.4 meters with a height difference of 129mm. An ordinary joint connects the elbow to the contact rail, ensuring that the train’s electric shoe can smoothly engage and disengage at rated speeds, maintaining consistent and safe power transfer.

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