What Are the Steps in the Manufacturing Process of UHPC Exterior Wall Decorative Lines? Analysis of the Standardized Production Process

With lightweight high strength, exquisite styling, and excellent durability, UHPC exterior wall decorative lines have become the preferred product for high-end building facade decoration. Their production must follow a standardized process flow to ensure product quality and appearance. Drawing on 28 years of UHPC production experience, Qinglong analyzes the core steps and key technical points of producing exterior wall decorative lines.

I. Detailed Design and Mold Fabrication

Detailed design is the foundation of production, requiring optimization of line profiles and structures according to the building facade requirements. Using BIM and Rhino parametric design software for precise modeling and optimized cross-sectional dimensions ensures a good fit between the lines and the wall. In a high-end residential project in Nanning, Qinglong used BIM technology to resolve the connection between the lines and the curtain wall. Mold fabrication must match the line profile: straight lines use steel or GRP molds, while complex curved lines use flexible molds. The mold surface must be ground and polished to ensure a smooth UHPC line surface, with tolerances controlled within ±1mm. Qinglong adopts a high-precision mold fabrication process, allowing molds to be reused more than 100 times, ensuring precise shaping while reducing production costs.

II. Raw Material Preparation and Precise Proportioning

Raw material selection must meet UHPC performance requirements: cement uses Grade 52.5 high-strength Portland cement, aggregate is 0.15-1.2mm quartz sand, fibers are steel fibers with a diameter of 0.2-0.3mm and a length of 12-15mm, and the active admixture is high-purity silica fume. Proportioning must be precisely controlled: water-binder ratio of 0.22-0.25, steel fiber content of 2% of the cementitious material mass, silica fume content of 15%-20%, and high-range water reducer content of 1.0%-1.2%. Through automated metering equipment, Qinglong controls raw material metering errors within ±0.5% to ensure accurate proportioning. Raw materials require pretreatment: quartz sand is dried to a moisture content of ≤0.5%, and steel fibers are dispersed to prevent agglomeration, ensuring quality in subsequent forming.

III. Mixing, Forming, and Vibration Compaction

Mixing uses a twin-shaft compulsory mixer: first add the aggregate and cement and mix for 2 minutes, then add water and admixtures and mix for 3 minutes, and finally add the steel fibers and mix for 2 minutes, with a total mixing time of ≥7 minutes to ensure uniform blending and fiber dispersion. Forming uses a casting process: the UHPC slurry is poured slowly into the mold to avoid air bubbles. During pouring, a high-frequency poker vibrator is used, vibrating for 20-30 seconds per point, ensuring the slurry fills the mold completely and densely. Through automated vibration equipment, Qinglong avoids under-vibration and over-vibration, reducing internal voids in components. For openwork decorative lines, a pre-embedded mold method is used to ensure precise hollow patterns. After casting, excess slurry on the mold surface is promptly cleaned to keep the line appearance neat.

IV. Steam Curing, Demolding, and Finishing

Steam curing is key to increasing strength and shortening the cycle, using a staged steam curing process: preheating stage (20-50℃, 2 hours) → constant temperature stage (85℃, 48 hours) → cooling stage (50-20℃, 2 hours). Qinglong's dedicated steam curing kiln precisely controls temperature and humidity, ensuring UHPC lines achieve a 28-day compressive strength of ≥150MPa. Demolding must wait until the component strength reaches more than 70% of the design value, using a combination of mechanical demolding and manual assistance to avoid component damage from forceful demolding. After demolding, the component surface is promptly cleaned to remove flash and burrs. Finally, surface finishing and inspection are carried out: sandpaper is used to polish surface defects, and a laser rangefinder checks the dimensional accuracy of the lines to ensure compliance with design requirements. Qualified products are labeled with a number and production date, then stored pending shipment. Through this standardized process, Qinglong ensures the stable quality of UHPC exterior wall decorative lines, which have been successfully applied in multiple high-end projects such as Shanghai Xinghewan and Guangzhou Agile.