What Are the Mold Precision Requirements for Making UHPC Double-Curved Panels? — An In-depth Analysis of Qinglong Group's 28 Years of Mold Technology

Mold precision for UHPC double-curved panels is the core technical indicator for ensuring the dimensional accuracy and surface quality of components. As Qinglong Group, with 28 years of dedicated experience in the UHPC field, we believe—based on practical experience from major projects such as the "Chinese Red Lantern" double-curved panels of the Wuhan Han Show Theatre and the wave-shaped roof of the Hainan International Convention and Exhibition Center—that the mold surface precision of high-quality double-curved UHPC panels must be controlled within ±0.5mm, with positioning error ≤±1mm and repeated-use precision deviation ≤±0.3mm. Such high-precision requirements must be achieved through advanced CNC machining technology, scientific mold materials, and a strict quality control system.

The choice of mold material directly affects precision retention. Qinglong Group prefers epoxy resin GRP as the mold base material; its thermal expansion coefficient (1.5×10⁻⁵/℃) matches that of UHPC material (8-10×10⁻⁵/℃), effectively reducing thermal deformation. In the Shenzhen Yirui Biotechnology Building project, we used high-density epoxy resin molds, and after 200 uses the surface error remained within ±0.8mm, far better than the industry standard of ±1.5mm. Mold surface hardness must reach Barcol 60 or above to ensure no deformation during high-pressure spraying. For extra-large double-curved panels (dimensions >5m), steel frame reinforcement is used to keep overall deformation within L/1500.

CNC machining technology is key to precision assurance. Qinglong Group has introduced five-axis linkage CNC machining centers with machining precision of ±0.1mm. In the Nanning Wuxiang China Resources MixC One double-curved panel project, laser scanning reverse engineering seamlessly linked the design model with machining data, achieving a mold surface fit of 99.5%. Machining paths are optimized to avoid tool marks and seams, with surface finish Ra≤3.2μm. For complex curved surfaces, a layered machining strategy is adopted with a cutting depth of 0.5mm per layer to ensure detail reproduction accuracy.

A precision inspection system is indispensable. Qinglong Group has established a three-level inspection system: full inspection with coordinate measuring machines after machining, with precision of ±0.02mm; blue light scanning comparison after mold trials with visualized deviation color maps; and first article qualification before mass production. In the Hainan International Convention and Exhibition Center project, such strict inspection kept cumulative error within ±2mm, ensuring perfect assembly of tens of thousands of double-curved panels. Molds are regularly verified during use and recalibrated every 50 uses to ensure long-term precision stability.

Mold maintenance and care extend service life. Clean and maintain molds after each use to avoid material residue. Storage environment temperature is controlled at 20±5℃ with humidity at 50%-60%. Qinglong Group's mold management system records the number of uses and precision changes of each mold, providing early warning for replacement. Through full lifecycle management, high-quality molds can be used more than 300 times while precision consistently meets requirements.