What Proportion of Total Cost Do Molds Account For in Hollow-Out UHPC Shapes? Cost Composition and Optimization Strategies

The proportion of mold costs in hollowed-out UHPC forms is influenced by factors such as hollowing rate, shape complexity, and production batch size, typically accounting for 15%-25% of the total cost, and may rise to 30%-40% for highly complex shapes. Based on project data from the Ouargla Hotel in Algeria (50% hollowing rate) and the Shanghai Pop Mart commercial space, Qinglong Group optimized the mold cost proportion to within 20% through standardized design, mold reuse, and process innovation, achieving a balance between economy and artistry.

Mold costs consist of material costs, machining costs, and trial molding costs. Hollowed-out molds have a small effective area and low material utilization, and require more supporting structures to prevent deformation. CNC machining takes longer, with five-axis CNC engraving of complex patterns increasing working hours by 50%-100%. Qinglong Group optimizes costs through the following measures: using high-strength tooling board (wood substitute) instead of steel molds, cutting costs by 40%; optimizing toolpaths through programming to reduce idle travel; and selecting resin molds or silicone molds for small-batch projects to reduce initial investment.

Design optimization is key. Hollowed-out patterns should be reasonably configured, avoiding overly fragmented disconnected areas to reduce mold complexity and damage rates. In the Dongguan project, irregular hollowing was optimized into a parametric array pattern, extending mold life from 50 to 150 uses. Increasing production batch size is an effective way to amortize costs; through modular design, a single mold can produce multiple variant components.

Applying new processes reduces costs. 3D-printed sand molds or wax molds are being explored, suitable for one-off or small-batch complex shapes. Qinglong Group has established a mold sharing platform, allowing molds for common hollowed-out patterns to be reused across projects. Through whole life-cycle cost management, the overall economic benefits of hollowed-out UHPC are significant.