U-PVC Union Pipe Fitting Mould: Design, Functionality, and Applications A U-PVC union pipe fitting mould is a precision tool used in the injection moulding process to manufacture union fittings for unplasticized polyvinyl chloride (U-PVC) piping systems. These fittings are essential for connecting, redirecting, or terminating pipes in plumbing, irrigation, and industrial fluid transport applications. The mould must meet stringent standards to ensure durability, leak-proof performance, and ease of installation. Design and Construction The mould is typically made from high-grade tool steel, such as P20 or H13, to withstand high-pressure injection cycles and resist wear. It consists of two primary halves—the core and cavity—which form the fitting’s internal and external geometries. Critical features include: - Precision Machining: The mould is CNC-machined to tight tolerances (±0.02 mm) to ensure dimensional accuracy, especially for threading or sealing surfaces. - Cooling Channels: Integrated cooling lines regulate temperature during production, reducing cycle times and preventing defects like warping. - Ejection System: Pins or plates eject the finished fitting without damage. - Venting: Small vents release trapped air to avoid voids or burn marks. Functionality The mould produces union fittings, which consist of three parts: a nut, a female end, and a male end. These components allow easy disassembly for maintenance without cutting the pipe. The mould must create: 1. Threads: Smooth, precise threads for a secure, leak-free connection. 2. Sealing Surfaces: Flanges or gasket seats to enhance pressure resistance. 3. Smooth Bore: Minimizes flow resistance and prevents sediment buildup. Production Process 1. Material Preparation: U-PVC pellets are dried and fed into the injection moulding machine. 2. Injection: Molten U-PVC is injected into the closed mould under high pressure. 3. Cooling & Ejection: The part cools, solidifies, and is ejected for post-processing (deburring, inspection). Quality Assurance Each fitting undergoes checks for: - Dimensional accuracy (OD, ID, thread pitch). - Pressure resistance (tested hydrostatically). - Surface finish (no cracks or deformities). Applications U-PVC union fittings are widely used in: - Potable water systems (due to U-PVC’s non-toxicity). - Chemical transport (resistant to corrosion). - Agricultural irrigation (lightweight and durable). Advantages of the Mould - Longevity: Hardened steel ensures 500,000+ cycles. - Efficiency: Multi-cavity designs boost output. - Customization: Adaptable for different sizes (e.g., ½" to 4"). In summary, a U-PVC union pipe fitting mould is a critical tool for producing reliable, high-performance fittings. Its precision engineering ensures consistency, while robust construction supports large-scale production, meeting global standards for plumbing and industrial applications.