SS254SMO Duplex Steel Pipe Bend Supplier. Contact us to get free quote and sample!
SS254SMO Duplex Steel Pipe Bend has a high molybdenum content of 6.0-6.5%, a nitrogen content of 0.18-0.22%, a chromium content of 19.5-20.5%, a nickel content of 17.5-18.5%, and contains 0.5-1.0% copper. This unique combination of ingredients provides an optimal balance between corrosion resistance and mechanical strength.
HT PIPE is a leading stockist and global exporter with over 15 years of expertise in international trade. We supply pipes, plates, round bars, and a comprehensive range of pipe fittings, flanges, and valves. Contact us now for free quotes and personalized product information.
Why are elbows a weak link in piping systems?
Erosion and corrosion concentration points: When corrosive fluids carrying solid particles flow through elbows, the sudden change in flow direction causes continuous impact and erosion on the inner wall of the elbow's outer curve, significantly accelerating material loss. Furthermore, stagnant flow zones easily form on the inner curve of the elbow, creating conditions for the accumulation of corrosive ions and localized corrosion (such as pitting and crevice corrosion).
Complex stress distribution: Under internal pressure and temperature loads, the stress distribution across the elbow cross section is extremely uneven. Hoop and axial stresses are redistributed at the bend, making the elbow a stress concentration area for the entire piping system, placing higher demands on the material's fatigue and creep strength.
A test of the manufacturing process's limits: Processing a straight pipe into an elbow that meets stringent dimensional tolerances and wall thickness requirements requires intense plastic deformation. For high-strength, high-work-hardening materials like 254SMO, the forming process itself is a severe test of the process technology.
SS254SMO Duplex Steel Pipe Bend Forming Process
uns s31254 bend Cold Bending
At room temperature, a straight pipe section is bent using a pipe bending machine equipped with a specialized mandrel or anti-wrinkle die. This is the most commonly used elbow manufacturing method, particularly suitable for small and medium diameters (DN15-DN300) and medium bend radii.
ss254smo pipe fittings Hot Bending (Induction Bending)
Hot forming is often used for elbows with large diameters, thick walls, or small bend radii (such as 1.5D). Among these, induction bending is the most advanced and commonly used technology. The tube blank is locally heated to a specific temperature range (approximately 1150-950°C) in the area to be bent using a medium-frequency induction coil. Then, top bending or drag bending is performed.
s31254 pipe bend Wall Thickness Control
Outer Curve Side: Due to tensile stress, the wall thickness decreases. This is the weakest part of the SS254SMO Duplex Steel Pipe Bend, and the reduced wall thickness must still meet the design pressure requirements.
Inner Curve Side: Due to compressive stress, the wall thickness increases.
asme b16.9 astm 254smo bend Solution Annealing
The SS254SMO Duplex Steel Pipe Bend is heated to 1150-1180°C and held at this temperature for a period of time to allow carbides and intermetallic phases (such as sigma phase) that may have precipitated during the cold/hot working process to fully dissolve into the austenite matrix. It is then rapidly quenched in water.
astm s31254 bend Pickling & Passivation
After solution treatment, the SS254SMO Duplex Steel Pipe Bend will have a layer of oxide scale on its surface, which must be removed by pickling (usually using a mixture of nitric acid and hydrofluoric acid). Subsequently, a very thin but extremely dense chromium oxide passivation film will spontaneously form on the fresh surface after pickling.
