ASTM A213 TP316L Longitudinal Weding Fin Tube For Reactor and Condenser

ASTM A213 TP316L Base Tube Composition

A213 TP316L Longitudinal Weding Fin Tube Making Process

1. Raw material preparation and inspection

• Base tube: Select ASTM A213 TP316L seamless stainless steel tube, check the outer diameter, wall thickness, surface quality and chemical composition to meet the standard requirements.
• Fin strip: Select TP316L stainless steel strip with matching performance, cut it into the required width and length, and remove burrs and oil stains on the surface.

2. Base tube pretreatment

• Carry out pickling and passivation treatment on the outer surface of the base tube to remove oxide scale and impurities, and form a dense passivation film to improve corrosion resistance and welding performance.
• Dry the base tube to ensure that the surface is free of water and oil.

3. Fin positioning and assembly

• Fix the fin strip longitudinally on the outer wall of the base tube according to the design requirements (fin height, fin spacing), and use a positioning fixture to ensure that the fin is parallel to the axis of the base tube and the gap between the fin and the base tube is uniform.

4. Longitudinal welding

• Adopt TIG welding (tungsten inert gas welding) process, which has the advantages of small welding deformation, high weld quality and no splashing.
• Fill welding wire with matching components during welding to ensure that the weld is fully fused and there is no defect such as porosity or incomplete penetration.
• Control welding parameters (current, voltage, welding speed) to avoid overheating of the base tube and fin, which will affect the material performance.

5. Post-welding heat treatment

• Carry out solution annealing treatment on the fin tube at a temperature of 1050 - 1100℃, and then cool it quickly. This step can dissolve the carbides precipitated in the weld and heat-affected zone, eliminate welding residual stress, and restore the corrosion resistance and toughness of the material.

A213 TP316L Longitudinal Weding Fin Tube FAQs

1. What is the difference between A213 TP316L longitudinal fin tube and transverse fin tube?

• Heat transfer characteristics: Longitudinal fins are suitable for heat exchange of fluid flowing along the axial direction of the tube, and the heat transfer efficiency is high when the fluid flow rate is high; transverse fins are suitable for cross-flow heat exchange, and the heat transfer efficiency is high when the fluid flows perpendicular to the tube axis.
• Structural strength: Longitudinal fins have better impact resistance and vibration resistance, and are not easy to wear and tear; transverse fins are easy to be damaged by fluid scouring under high flow rate.
• Cleanability: The surface of longitudinal fin tube is smooth and not easy to accumulate dust and dirt, and the cleaning is simple; the gap between transverse fins is easy to block and difficult to clean.

2. What is the maximum operating temperature and pressure of A213 TP316L longitudinal fin tube?

• The maximum continuous operating temperature is about 650℃. When the temperature exceeds 700℃, the material strength will decrease significantly, and the corrosion resistance will also decline.
• The maximum operating pressure depends on the wall thickness of the base tube and the diameter of the fin tube. Generally, it can bear a pressure of 1.6 - 10 MPa under the condition of meeting the design standard.

3. How to prevent the fin from falling off during use?

• Ensure that the welding quality meets the requirements, and avoid defects such as incomplete penetration and porosity in the weld.
• Avoid drastic changes in temperature during use (such as rapid heating and cooling), which will cause excessive thermal stress and lead to weld cracking.
• Regularly inspect the fin tube, and repair the loose or cracked welds in time.

4. Can A213 TP316L longitudinal fin tube be used in high chloride ion environment?

• Yes. TP316L stainless steel contains molybdenum element, which can effectively improve the pitting corrosion resistance of the material. It is suitable for environments with chloride ion concentration ≤ 10000 ppm (such as seawater, salt-containing industrial wastewater).
• When the chloride ion concentration is too high, it is recommended to carry out surface anti-corrosion treatment (such as coating anti-corrosion coating) or select higher-grade stainless steel materials.

A213 TP316L Longitudinal Weding Fin Tube Application