Distribution union bush malleable iron galvanised

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The Georg Fischer distribution union bush 378 flat seat is an engineered malleable cast iron component designed for modular piping assemblies requiring an integrated auxiliary takeoff within a demountable connection. Manufactured from high-grade whiteheart malleable cast iron conforming to EN-GJMW-400-5 under Design Symbol A and protected by a durable hot-dip galvanised zinc coating, the fitting provides superior mechanical durability and high corrosion resistance across potable water, heating, gas, and industrial distribution installations. Structurally configured as the core distribution element of figure 338 unions, the component incorporates three dedicated connection geometries: an external taper jointing thread R at the primary male connection adhering to EN 10226-1 and ISO 7-1 for pressure-tight sealing on the threads, an external parallel fastening thread G class B adhering to EN ISO 228-1 with a precision-machined flat seat surface designed to receive a union nut and a flat sealing gasket, and a centrally integrated female Rp 1/2 perpendicular branch with parallel internal jointing threads to accommodate branch monitoring instrumentation, drainage, air venting, or secondary pipework takeoffs. The flat-face union interface allows rapid radial assembly and disassembly of downstream piping modules without rotating or displacing adjacent fixed pipe runs, ensuring reliable sealing through axial mechanical compression applied by the union nut against an elastomer or fibrous flat gasket. Engineered to withstand rigorous mechanical stresses, thermal fluctuations, and vibration, the fitting is rated for operating pressures up to 25 bar across temperatures ranging from -20 degrees Celsius to 120 degrees Celsius, and up to 20 bar at elevated temperatures reaching 300 degrees Celsius, with intermediate values interpolated linearly. Each unit is individually tested for leak tightness, ensuring long-term operational integrity and dependable sealing in demanding building service networks and process pipelines.