Malleable cast iron union Bronze to Iron

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The Georg Fischer malleable cast iron union Bronze to Iron, designated under ISO/EN U11 and Figure 342, is an engineered detachable pipe fitting designed to establish a mechanically robust, dismountable inline connection between threaded piping runs in industrial, utility, and heating systems. Manufactured from high-grade decarburised annealed white malleable cast iron type EN-GJMW-400-5 and equipped with a precision-machined bronze-to-iron seating profile, the fitting operates via a three-part assembly consisting of a threaded union bush, a matching union end, and an external ISO 228-1 fastening thread union nut. Sealing is achieved through direct metal-to-metal contact between the spherically contoured bronze face and the complementary tapered iron seat, producing a high-integrity seal under axial compression without requiring elastomeric O-rings or flat cut gaskets. This metallic spherical taper geometry ensures exceptional sealing efficiency and accommodates slight axial alignment variations while effectively absorbing tensile, compressive, and vibrational pipeline stresses. Threaded connections feature precision parallel internal Rp jointing threads manufactured in accordance with EN 10226-1 and ISO 7-1, ensuring tight thread engagement and full compatibility with standard industrial steel pipework. The union is engineered for operating temperatures ranging from -20 degrees Celsius up to 120 degrees Celsius at a maximum permissible operating pressure of 25 bar, with continuous capability extending to elevated service parameters up to 210 degrees Celsius at 20 bar. Available in black cast or hot-dip galvanised finishes, this heavy-duty union enables straightforward radial disassembly of pipeline sections, regulating valves, pumps, and inline equipment, facilitating rapid servicing, maintenance, and system modifications while maintaining total joint reliability across closed-loop distribution networks.