Logistique de Parc à Tuyaux et Choix du Pont Portique : Poutres Treillis vs. Caissons et Manutention

1. Logistics: The Unsung Heart of a Precast Pipe Plant

In a high-capacity concrete pipe plant, a single suspension roller machine or vertical core vibration unit produces 40 to 80 heavy pipe sections per shift, weighing between 1.5 tons and 12 tons each. Every single pipe must be transported from the forming machine into steam curing pits, lifted out to the demolding yard, stripped from its steel mold, and transferred to the finished curing stockyard.

If gantry cranes are undersized, lack variable micro-speeds, or suffer excessive downtime, the entire forming plant grinds to a halt.

2. Gantry Crane Architecture: Box Girder vs. Truss Girder

HLY supplies two primary gantry crane structures for precast facilities:

1. Box Girder Gantry Cranes (绠卞瀷姊侀棬寮忚捣閲嶆満): Built from solid welded steel box sections. Offers maximum torsional rigidity and weather protection for indoor/outdoor casting bays. Recommended for high-tonnage lifting (10T鈥?0T).

2. Truss Girder Gantry Cranes (妗佹灦姊侀棬寮忚捣閲嶆満): Constructed from welded structural angle and pipe steel. Features low self-weight and minimal wind resistance. Ideal for large outdoor open storage yards subjected to high coastal wind speeds.

3. Tonnage Sizing & Span Sizing Guide (5T to 20T)

Sizing the gantry crane depends on the heaviest combined load: the weight of the largest pipe plus the weight of its steel mold and rigging fixtures.

4. Specialized Pipe Rigging: C-Hooks, Balance Beams & Clamps

Standard wire rope chokers wrap around pipe exteriors and exert crushing hoop forces on newly stripped green concrete, causing hairline cracks.

HLY supplies dedicated precast rigging solutions:

鈥?Counterbalanced Internal C-Hooks (C鍨嬪悐鍏?: Slips inside the pipe barrel with polyurethane protective pads, lifting from the inner crown without marking exterior joint profiles.

鈥?Spreader Equalizer Beams (骞宠　鍚婃): Suspends multiple lifting chains vertically, eliminating lateral compression on mold edges during demolding.

鈥?Scissor Friction Clamps: Automatic mechanical latching clamps for rapid handling of precast U-channels and box culvert lids.

5. Safe Yard Stacking Guidelines per GB/T 11836 & OSHA

To prevent catastrophic yard roll-aways and bottom-tier crushing, stacking heights must follow strict geometric tiers:

鈥?DN300 to DN600 mm: Maximum 4 tiers high (Pyramid stacking with wedge blocks at base).

鈥?DN800 to DN1200 mm: Maximum 2 tiers high with timber dunnage between layers.

鈥?DN1400 to DN3000 mm: Single tier only, rested on level compacted crushed stone or concrete dunnage pads.

6. Crane Rail Alignment, Wind Anchors & Safety Protocols

Outdoor gantry cranes require sturdy P38 or P43 heavy rail tracks laid on reinforced concrete ground foundations. HLY cranes include motorized rail clamps, rail-sweeping guards, overload limiters, and ground anchor pins to secure the crane during severe storms.

7. Frequently Asked Engineering Questions