Galvanised malleable iron union

  Datasheet (PDF)

Georg Fischer galvanised malleable iron unions 346 provide detachable, pressure-tight pipe connections engineered with a spherical seat design compliant with ISO/EN U11 standards. Specifically manufactured from decarburised annealed whiteheart malleable cast iron conforming to Design Symbol A, these fittings incorporate spherically machined metallic mating faces that permit smooth angular compensation of up to 6 degrees. This spherical seat geometry absorbs pipeline deflections, structural settling, and minor misalignments without inducing excessive mechanical stress or compromising joint integrity. Each assembly comprises an internally threaded union end, a union bush, and an ISO 228-1 G-thread union nut (figure 374 G) that draws the spherical metallic surfaces into uniform compression. Internal connection ports feature parallel Rp threads standardized in accordance with EN 10226-1 and ISO 7-1, ensuring exact engagement and dependable thread sealing when paired with appropriate jointing media. The hot-dip galvanized protective coating, applied through molten zinc immersion, establishes durable iron-zinc alloy layers beneath a pure zinc exterior to resist atmospheric degradation and operational corrosion across liquid and gas transport pipelines. Rated for maximum operating parameters up to 25 bar across temperatures from -20 degrees Celsius to 120 degrees Celsius, and up to 20 bar at elevated temperatures reaching 300 degrees Celsius, the union facilitates rapid system prefabrication, straightforward component dismounting, and simplified piping maintenance across industrial utility and process installations.