What Are the Mold Precision Requirements for Producing UHPC Double-Curved Panels?

Mould precision for producing UHPC double-curved panels must meet three core requirements: dimensional deviation ≤±0.5mm, curved surface precision ≤±0.3mm, and joint gap ≤0.2mm, in accordance with the industry standard "Ultra-High Performance Concrete (UHPC) Exterior Wall Panels". Through five-axis CNC machining and 3D inspection technology, Qinglong has achieved a 100% mould precision compliance rate, with a shape replication error of ≤±0.8mm for the Shanghai New World Plaza double-curved panel project.

I. Core Precision Indicators: Quantified Control of Shape Restoration

Precision indicators directly determine the forming quality of double-curved panels. Dimensional deviation: the length, width, and height deviations of the mould are ≤±0.5mm, with diagonal deviation ≤±0.8mm, ensuring the double-curved panel matches the design dimensions; Qinglong uses laser rangefinders for mould dimensional inspection with an accuracy of ±0.01mm. Curved surface precision: the deviation of any point on the double-curved surface from the design surface is ≤±0.3mm, avoiding "surface sagging" and "bulging"; Qinglong uses 3D laser scanning inspection, achieving a surface fit rate of 99.8%. Jointing precision: the joint gaps of modular moulds are ≤0.2mm, and joint surface flatness ≤0.1mm/m, preventing slurry leakage that causes surface defects; Qinglong fills the joints with sealant, achieving a slurry leakage rate of 0.

II. Mould Material and Machining Process: The Foundation of Precision

Materials and processes determine the upper limit of mould precision. Mould material: GRP moulds (surface roughness ≤0.05mm) or steel moulds (high strength, strong reusability) are preferred to avoid the deformation of wooden moulds; Qinglong's double-curved panel moulds are mainly made of GRP with a service life of ≥50 uses. Machining process: five-axis CNC machining centers precisely mill according to BIM 3D models, with machining errors ≤±0.1mm; Qinglong's five-axis machining equipment has a spindle speed of ≥15000rpm, producing smooth curved surfaces without tool marks. Mould reinforcement: double-curved moulds require stiffening ribs (spacing ≤500mm) to prevent mould deformation during casting; Qinglong's stiffening ribs are made of square steel, increasing mould rigidity by 40%.

III. Qinglong's Precision Control and Project Practice

Full-process control ensures stable mould precision. Mould calibration: after machining, pre-assembly calibration is performed to adjust surface deviations and joint gaps; Qinglong conducts 3D scanning verification after pre-assembly, with non-conforming parts immediately reworked. Trial production verification: after the first double-curved panel is produced, its dimensions and curved surface precision are tested to back-calibrate the mould; Qinglong's first-article inspection pass rate is 95%, with moulds exceeding deviation limits rectified within 24 hours. Project cases: the UHPC wood-grain translucent double-curved panels of Shanghai New World Plaza have mould dimensions of 3245×3530mm and surface precision ≤±0.3mm; after forming, the double-curved lines are smooth and the light transmission effect is uniform. For the double-curved panel moulds of the Guangxi New Media Center, through BIM modelling and five-axis machining, all panels achieve shape replication errors ≤±0.5mm, becoming a highlight of this Nanning landmark.