Distribution Tee reducing on branch malleable iron galvanised

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The Georg Fischer 338 distribution union flat seat provides a robust, demountable inline connection point integrated with a dedicated lateral branch takeoff for commercial, industrial, and utility piping installations. Manufactured from high-grade decarburised annealed whiteheart malleable cast iron EN-GJMW-400-5, this fitting features an impermeable hot-dip galvanised surface that provides comprehensive long-term protection against corrosion and ensures complete suitability for potable water lines, cooling systems, heating networks, compressed air, and gas distribution. The precision-engineered three-piece configuration comprises a flat seat union end with internal parallel thread Rp, an ISO 228 fastening union nut, and an extended distribution union bush terminating in an external taper pipe thread R on the main run, complemented by an integral Rp 1/2 inch parallel internal threaded lateral branch. This integrated manifold geometry establishes a dependable, rigid takeoff connection ideal for installing pressure gauges, test points, air vents, or drain cocks directly into the run without requiring additional inline tees or extra joints. Utilizing a planar sealing interface, the assembly compresses a flat sealing gasket between machined mating faces upon tightening the union nut, delivering absolute pressure-tight containment while allowing rapid radial disconnection of pipeline components without spreading or dismantling adjoining pipe runs. Pipe jointing threads conform strictly to EN 10226-1 and ISO 7-1 for sealing on the threads, while fastening threads follow EN ISO 228-1 specifications. Built for demanding duty cycles, the fitting is rated for a maximum permissible working pressure of 25 bar across temperatures from -20 to 120 degrees Celsius, and up to 20 bar at elevated temperatures reaching 300 degrees Celsius. Available in nominal run sizes of 3/4 inch, 1 inch, and 1 1/4 inch with union nut thread sizes from 1 1/4 inch to 2 inches, the union incorporates standardized external hexagon wrench flats to facilitate exact torque application and rapid alignment in prefabrication workflows based on the z-dimension method.