How Do UHPC Single-Curved and Double-Curved Panels Differ in Mold Requirements? Surface Complexity and Qinglong Group Mold Technology Classification

UHPC single-curved panels and double-curved panels have fundamental differences in mold requirements in terms of "geometric dimensions, processing techniques, and cost investment," directly leading to a 3-5x gap in mold manufacturing lead time and cost. Single-curved panel (bending in one direction) molds can use lower-cost GRP molds or CNC-milled tooling board molds, with a production cycle of 3-5 days and a cost of approximately 800-1500 RMB/m²; double-curved panels (bending in two directions) must use five-axis CNC-machined tooling board molds or metal molds, with a cycle of 7-15 days and costs as high as 3000-5000 RMB/m². In the Wuhan Han Show Theater project, Qinglong Group developed a modular mold system for 9,000 double-curved panels, optimizing the number of molds by 40% through parametric design, keeping mold costs within a reasonable range while ensuring precision. Mold differences not only affect production costs but also determine the freedom and precision of shape realization.

Geometric complexity is the fundamental difference. Single-curved molds can be approximated as developable surfaces and machined with three-axis machines; double-curved molds are non-developable surfaces and require five-axis simultaneous machining. Qinglong Group introduced German five-axis CNC (positioning accuracy ±0.02mm), reducing the surface error of double-curved molds to ≤0.3mm. In the Hainan International Convention and Exhibition Center wave roof project, this high-precision mold ensured the perfect splicing of the 120,000-square-meter roof.

Material and process requirements differ. Single-curved molds mostly use tooling board or resin materials with a lifespan of about 200 uses; double-curved molds require high-strength tooling board or aluminum plates with a lifespan requirement of ≥500 uses. Through surface hardening treatment (hardness HRC≥55) and nano-coating, we have increased mold lifespan to more than 800 uses. Mold durability directly relates to the economics of mass production.

Cost control requires scientific management. Qinglong Group established a mold database to standardize and serialize molds with common curvatures. For special shapes, modular combined design is adopted to reduce the number of non-standard molds. At the Nanning production base, through mold sharing and remanufacturing repairs, we reduced the mold cost ratio from the industry average of 25% to 18%. The tiered mold strategy achieves a balance between art and economics.