Concrete Sleeper Production Line

● Mould Cleaning & Release Agent Spraying: Steel moulds (2×4 / 2×5 grouping, 8–10 sleepers per frame) are automatically deslagged and dust cleaned, followed by CNC-controlled uniform release agent spraying without missing spots.

● Sleeve & Fitting Mounting: Automatic screwing of embedded insulated/anchoring sleeves, spiral stirrups and grout retaining clamps with positioning tolerance within ±0.5 mm.

● Reinforcement Loading & Prestressing: High-strength steel wires/bars are cut to fixed length, headed, then loaded into moulds; fully automatic prestressing machines tension reinforcement to designed stress and lock the prestress.

● Concrete Pouring & Vibration: Dry-stiff C60 concrete is placed in layers by automatic distributing machine at incoming temperature of 5–30℃.Two-stage vibration process: basic vibration for compaction + loaded vibration (≥5kPa) to prevent slurry leakage.

● Surface Finishing & Pre-curing: Surface finished manually or mechanically; moulds stacked in 3–4 layers for static initial setting for around 2 hours.

● Steam Curing (four-stage intelligent curing kiln/tunnel): Resting period (1–2 h) → temperature rise (15–20℃/h) → constant-temperature curing (45–55℃, 8–12 h) → cooling down (≤15℃/h).

● Prestress Release & Demoulding: Prestress is released when concrete strength exceeds 75% of design value (approx. 40 MPa); 180° turnover demoulding via vibration/inertia stripping, after which empty moulds circulate back to upstream.

● Finished Product Finishing & Stockpiling: Cut intermediate connecting rebars, edge trimming, visual inspection and static load test; qualified sleepers stacked for 28-day natural curing.