What Are the Production Processes of GRC Manufacturers? 8 Key Steps from Raw Materials to Finished Products

Exquisite GRC production craftsmanship is the dual guarantee of artistic form and structural safety. The high quality of GRC products stems from mature production processes, and differences in process levels among manufacturers directly affect product strength, durability, and aesthetics. As a national high-tech enterprise that participated in formulating the GRC industry standards, Qinglong Group breaks down the 8 key process stages of GRC production, explains in detail the characteristics and application scenarios of mainstream production processes, and demonstrates the process strength of a professional GRC manufacturer.

1. Raw Material Proportioning and Mixing Process: Laying the Foundation for Product Performance

The first step in GRC production is raw material proportioning and mixing, which is the core stage determining product performance. Raw materials mainly include alkali-resistant glass fiber, high-grade cement, natural aggregates, and additives (such as water reducers and retarders). Professional manufacturers develop precise proportioning schemes based on product applications. For example, Qinglong's mix for curtain wall components contains no less than 4% alkali-resistant glass fiber, ensuring a product flexural strength of ≥15MPa; for landscape components, the aggregate ratio is appropriately increased to improve wear resistance. The mixing process uses an automated mixing station with a PLC control system to control mixing time and speed, ensuring uniform mixing of raw materials and avoiding problems such as fiber agglomeration and uneven proportioning caused by manual mixing. Qinglong's mixing process can raise raw material mixing uniformity to over 95%, laying a solid foundation for stable product performance.

2. Mold Making Process: The Core Guarantee for Adapting to Different Forms

The mold making process directly determines the forming precision of GRC products. Mainstream molds include steel molds, GRP molds, silicone molds, and others. Steel molds are suitable for mass-produced standard components such as decorative moldings and flat panels; they feature high strength and long service life, and Qinglong's steel molds can be reused more than 500 times, effectively reducing mass production costs. GRP molds are suitable for irregular components and curved forms, such as the hyperbolic exterior wall panels of the Guangxi New Media Center; GRP molds can precisely replicate complex curved surfaces with forming precision of up to ±1mm. Silicone molds are suitable for fine reliefs and textured forms, such as the "Guancao" woven texture of the Dongguan Women and Children's Activity Center; silicone molds can capture delicate texture details with a fidelity of over 95%. After mold making is completed, trial production and adjustments are required to ensure compliance with design requirements.

3. Forming Processes: Characteristics and Application Scenarios of Mainstream Processes

The core GRC forming processes mainly include the spray-up process, the premix process, and the casting process. The spray-up process involves spraying the mixed raw materials into the mold through a spraying machine while simultaneously laying alkali-resistant glass fiber; it is suitable for thin-walled components and complex forms, such as the 15mm-thick carved GRC panels of the Wuhan Han Show Theatre, where the spray-up process achieved the combination of thin walls and high strength. The premix process involves mixing glass fiber with the raw materials in advance, then pouring the mixture into the mold and vibrating it into shape; it is suitable for thick-panel components and load-bearing components, such as landscape seating and flower beds, and can improve product density and compressive strength. The casting process involves pouring the raw materials into the mold to form naturally; it is suitable for large components and simple forms, such as large Roman columns and wall panels, with relatively high production efficiency. Qinglong selects the appropriate forming process according to product type and design requirements, ensuring a balance between product quality and production efficiency.

4. Curing Process: The Key to Enhancing Product Strength and Durability

Formed GRC components must undergo a curing process to reach the designed strength and durability. Mainstream curing methods include natural curing and steam curing. Natural curing is suitable for small projects and products with low strength requirements, with a curing cycle of 14-21 days, and is greatly affected by ambient temperature and humidity. Steam curing is suitable for large projects and products with high strength requirements; by controlling the temperature (40-60℃) and humidity (≥90%) in a steam curing chamber, the curing cycle is shortened to 3-5 days, rapidly increasing product strength with better strength uniformity. Qinglong mainly adopts the steam curing process combined with subsequent natural curing, ensuring that products achieve a 28-day compressive strength of ≥40MPa and withstand ≥200 freeze-thaw cycles, meeting usage requirements in different environments.

5. Cutting and Finishing Process: A Necessary Stage for Ensuring Installation Precision

After curing, GRC components must undergo cutting and finishing to ensure installation precision. The cutting process uses CNC cutting machines to cut components to size according to installation requirements, with cutting precision of up to ±1mm, avoiding dimensional deviations that affect jointing. Finishing includes surface grinding, repair, coloring, etc. Qinglong combines mechanical grinding with manual repair to control surface flatness error within ±2mm. For colored GRC products, a mineral pigment coloring process is adopted to ensure uniform color and strong weather resistance, such as the colored openwork carved GRC panels of the Nanning Liyuan Hotel, whose color showed no obvious fading after 5 years.

6. Quality Inspection Process: Controlling Product Quality Throughout the Entire Process

Professional GRC manufacturers set up quality inspection checkpoints throughout the entire production process to ensure product compliance. Raw material inspection includes fiber tensile strength, cement grade, aggregate particle gradation, etc.; semi-finished product inspection includes component thickness, fiber distribution, density, etc.; finished product inspection includes flexural strength, compressive strength, dimensional accuracy, surface quality, etc. Qinglong has a well-equipped testing laboratory with tensile testing machines, compression testing machines, 3D scanners, and other equipment. Every batch of products must be inspected and can only leave the factory after passing, with a product pass rate of over 99.8%.

GRC production craftsmanship is a systematic engineering endeavor; from raw material proportioning to finished product inspection, every stage affects product quality. With 28 years of process accumulation, Qinglong Group has developed a mature and complete production process system that can meet the production needs of both standard and customized products, providing GRC products that combine artistic beauty with structural safety for various projects.