Stainless Steel 316L Single Sphere Rubber Expansion Joint DN25-DN3000 For Pump Manifold

Stainless flanges make sense wherever the outside of the pipe is as aggressive as the inside. SS316L resists chlorides, so these joints are used on sea water cooling, desalination, coastal plant and food factories that wash down with chlorinated water every shift. The molybdenum content in 316L also protects the weld heat affected zone, so flange to hub joints stay sound in wet service.

The single sphere rubber body remains the flexible element, with a nylon cord carcass and steel wire bead to hold pressure. That division of labour is deliberate: stainless handles the environment, rubber handles the movement. The assembly is available from DN25 to DN3000, covering everything from small chemical dosing manifolds to large sea water intake headers on a single specification.

• SS316L Flanges: Molybdenum bearing stainless steel resists chloride pitting and crevice corrosion in coastal and sea water duty.
• Sea Water Proven: Selected for intake, outfall and cooling circuits where galvanised or painted carbon steel flanges fail quickly.
• Wide Size Range: DN25 to DN3000 covers dosing manifolds, pump headers and large intake lines from one product family.
• Single Sphere Flexibility: Absorbs axial, lateral and angular movement, protecting pump casings and manifold welds from pipe strain.
• Cord Reinforced Body: Nylon plies and a steel wire ring keep the arch stable under pressure and surge without ballooning.
• Hygienic Option: Available with smooth bore and cleaned finish for food, beverage and pharmaceutical wash-down areas.

Sea water cooling systems, desalination pre-treatment, aquaculture sea pens, coastal fish processing plants and chemical manifolds are the main applications. The joint is also used on pump suction headers where several pumps share a common manifold and each branch needs isolation from the next machine's vibration. In food plants, stainless ends survive daily chlorinated wash-down without the rust staining that carbon steel flanges leave on floors and product.

Stainless flange faces are protected with plastic caps and interleaving to prevent scratching, then the unit is film wrapped, cartoned and crated in a wooden case. Passivation of the stainless surface is completed before packing. We issue the SS316L mill certificate, pressure test record and dimensional report with each shipment, and can supply pickled and passivated finish on request.