Steel nipple

  Datasheet (PDF)

Georg Fischer type 531 barrel nipples engineered from high-grade steel provide a compact and dependable inline jointing solution for industrial and mechanical piping installations. Designed with continuous external parallel fastening threads conforming to EN ISO 228-1 tolerance class B, these components facilitate direct coupling between female-threaded fittings, valves, manifolds, and process equipment where axial installation space is strictly limited. The precision-machined G-thread geometry guarantees smooth mechanical engagement, uniform distribution of tensile and compressive stresses along the mating threads, and high structural rigidity under system vibrations and continuous operating pressures up to 25 bar at temperatures from -20 degrees to +120 degrees Celsius, maintaining dependable pressure containment up to 20 bar at elevated temperatures reaching +300 degrees Celsius. Unlike taper threads that rely on metallic thread deformation to seal, the parallel fastening thread configuration establishes a rigid mechanical union that seals effectively against flat seating faces using compatible elastomeric, fiber, or technical gaskets, preventing over-torquing and allowing straightforward disassembly during scheduled servicing. The robust steel body features an electroplated zinc surface finish that shields against external atmospheric oxidation in closed-loop heating, cooling, compressed air, and non-potable industrial utility distribution networks. Controlled manufacturing ensures dimensional consistency across the 3/8 inch to 1 inch dimension range, delivering standardized overall lengths between 23 mm and 35 mm to simplify prefabrication and maintain precise axis alignment across complex pipe runs.