GRC Component Demolding Timing: Seize the Optimal Point to Avoid Damage

Demolding is a critical process in GRC component production, and the choice of demolding timing directly affects the forming quality and performance of components. Demolding too early or too late can both lead to component damage and deformation, affecting project schedules. Qinglong Group, with 28 years of GRC production experience, has precisely mastered the optimal demolding timing for different types of GRC components through extensive testing and project practice.

The core of demolding GRC components lies in grasping the rhythm of strength development in the base material; demolding operations may only be carried out when component strength reaches at least 70% of the design strength. In production, Qinglong combines compressive strength testing with experienced judgment to ensure the demolding timing is precise and accurate.

Criteria for Determining the Optimal Demolding Timing: Strength, Temperature, and Component Type

Meeting strength requirements is the core criterion. When demolding conventional GRC components, compressive strength must be no less than 10MPa, which can be verified through test cube testing or rebound hammer inspection. Ambient temperature affects strength development: at normal temperatures of 20-25℃, ordinary flat panel components require approximately 24-48 hours before demolding; in low-temperature environments, strength develops slowly and demolding time must be extended to more than 72 hours. Component type must also be considered—simple-shaped components such as flat panels and moldings can be demolded relatively early, while complex-shaped components such as double-curved surfaces, openwork designs, and large sculptures involve complex stress distribution and require extended demolding time to ensure adequate strength development. In the Shanghai Astronomy Museum public art project, Qinglong applied a 72-hour demolding standard for GRC sculpture components over 3 meters in size, effectively avoiding deformation and damage.

Hazards of Improper Demolding Timing: Too Early Prone to Breakage, Too Late Hard to Remove

Demolding too early, when component strength is insufficient, leads to edge and corner damage, surface dusting, and even bending deformation; in severe cases, components may fracture outright. Demolding too late causes the GRC base material to adhere too tightly to the mold, making surface tearing likely during removal and potentially damaging the mold. Qinglong once encountered premature demolding in a project: a batch of GRC moldings achieved only 5MPa strength at demolding, resulting in a breakage rate as high as 30% and forcing reproduction.

Qinglong's Standardized Demolding Process: Refined Management from Preparation to Operation

Qinglong has established a standardized demolding workflow: before demolding, clear debris around the mold and check whether component strength meets requirements; during demolding, use dedicated tools and follow the principle of "perimeter first, then center; top first, then bottom," avoiding forcible removal; after demolding, promptly label and cure the components, repairing any minor damage immediately. In the Wuhan Han Show Theatre project, Qinglong used this process to ensure an intact rate above 99% for thousands of complex-shaped GRC components after demolding.

Grasping the optimal demolding timing for GRC components is a key step in producing high-quality components. 28 years of technical expertise have enabled Qinglong to accumulate rich demolding experience, allowing precise judgment of demolding timing based on different environments and component types. Standardized demolding operations both safeguard component quality and improve production efficiency, providing strong support for smooth project progress.