Seamless Stainless Steel Concentric Reducer

A symmetrical conical butt-weld pipe fitting where the centerline of large and small ends remains coincident. Manufactured from seamless stainless steel pipe through pressing, reducing, or expanding forming processes.

1. Raw Material Inspection: Selection of qualified seamless stainless steel pipe (304, 316L, 321, etc.). Verification of material test certificates, surface condition, and pipe dimensions to eliminate cracks, pits, and other defects.
2. Cutting: Cutting seamless pipe into blank pieces according to drawing specifications. Removal of burrs from cutting ends.
3. Forming (Press Reducing/Expanding): Placement of pipe blank into forming mold. Application of hydraulic force to compress one end for diameter reduction (reducing forming). For certain specifications, small end expansion is possible. Formation of tapered concentric shape through cold forming process suitable for stainless steel.
4. Trimming & End Beveling: Removal of surplus material post-forming. Machining of both ends to create butt-weld bevels, ensuring flatness and proper welding angles.
5. Solution Heat Treatment: Performance of solution annealing to eliminate internal stress from cold forming. Restoration of mechanical properties and corrosion resistance of stainless steel.
6. Inspection:
   • Dimensional verification: Measurement of large end, small end, length, and wall thickness
   • Visual inspection: Examination for surface defects
   • NDT inspection: Penetrant testing as required
   • Material verification
7. Surface Treatment: Pickling and passivation to remove oxide layer and form anti-corrosion passivation film. Bright polishing available upon customer request.
8. Marking & Packaging: Clear marking of material grade, specification, standard, and heat number. Proper packaging to ensure safe transportation.