Bright Annealed ASTM A269 TP304 Stainless Steel Seamless Tubes For Evaporator 4" 18BWG

Bright Annealed ASTM A269 TP304 Stainless Steel Seamless Tubes For Evaporator 4" 18BWG

ASTM A269 TP304 bright annealed tubes are austenitic stainless steel tubes, which can be seamless or welded. These stainless steel tubes have different surface finishes, such as bright annealed, pickled and annealed, and so on, which can be made according to clients’ requests. They are widely used in applications, like industrial fluid application, food processing plant, evaporator, chemical industry, sugar refinery, water cooling tower, instrumentation, hydraulic lines, and heat exchanger tube, etc.. YUHONG GROUP mainly manufactures ASTM A269 TP304 stainless steel tubes from 6mm diameter to 152.4mm diameter. And the wall thickness can be made from 0.5mm to 3.4mm. In addition to SS304 material, we can also provide TP304L, TP304H, TP316, TP316, TP316L, TP316Ti, TP317, TP347, TP347H, TP321, TP310S, etc..

Different Surface Finishes:

• Bright Annealed (BA): The tube is annealed in a controlled atmosphere furnace (bright annealing furnace). This prevents oxidation and scaling. The result is a smooth, shiny, mirror-like surface. This finish does not require pickling.
• Pickled and Annealed (AP): The tube is annealed in a standard air furnace, which creates a black oxide scale. This scale is then removed by pickling (acid bath), leaving a matte grey, dull, but clean surface.
• Polished (Mechanical Polish): Starting from a pickled or bright annealed base, the tube is mechanically polished to achieve specific grit finishes (e.g., 180 grit, 320 grit, 400 grit, 600 grit, etc.) for aesthetic or ultra-clean applications.

Chemical Composition (ASTM A269 TP304 / UNS S30400):

Mechanical Properties:

Key Advantages and Features of TP304 Seamless Tubes:

• Excellent Weldability and Formability: The 18-8 chromium-nickel composition makes it easy to fabricate.
• Superior Corrosion Resistance: Offers good resistance to oxidation and a wide range of corrosive media, including foodstuffs, organic chemicals, and atmospheric exposure.
• Hygienic Surface (BA): The bright annealed finish is extremely smooth and non-porous, preventing bacterial growth and making it easy to clean—critical for pharmaceutical and food processing.
• Excellent Low-Temperature Toughness: Austenitic stainless steels retain their toughness at cryogenic temperatures.
• High Ductility: The 35% elongation minimum allows for easy bending and flaring operations without cracking.

Applications of SS304 Seamless Tubes:

• Instrumentation: Sensing lines for pressure, temperature, and flow transmitters.
• Hydraulic & Pneumatic Systems: High-pressure fluid transmission lines in industrial machinery.
• Pharmaceutical & Biotechnology: Transport of clean steam, purified water, and process fluids where hygiene is paramount.
• Food & Beverage Processing: Dairy lines, breweries, and food handling equipment.
• Chemical Processing: Transfer lines for mild chemicals and solvents.
• Heat Exchangers: Small diameter tubing for heat transfer applications.
• Aerospace & Automotive: Fuel and oil lines.
• General Engineering: Bearing tubes, mechanical parts, and shafts.