ASTM A376 TP347H / UNS S34709 Stainless Steel High Frequency Welded Spiral Fin Tube​

Alloy 347H ( UNS S34709 ) is Niobium/Tantalum stabalized Stainless Steel similar to AISI 347 with higher carbon content for performance at higher elevated temperature. S34709 offers higher mechanical properties including better creep & stress resistance. 347H is superior in intergranular corrosion at temperatures in chromium carbide preciptation range.

Spiral Fin Tube the Connotation of High Frequency Welding

High frequency welding is a welding technology, there are two kinds of induction welding and contact resistance welding.

The welding system has below three kinds:

1. Solid plastic pressure welding - the edge of the tube billet heating to 1300 degrees Celsius, the plastic state at 1350, and then under the pressure of the pressure of the roller to the oxide film extrusion, at the same time, through the high temperature to make both sides of the edge welded together, the compression strength of more than 40 - 50MPa.

2. Semi molten welding - heat the edge of the tube into the semi molten state, through the extrusion roll extrusion, the extrusion of the liquid film extrusion, and complete welding, the extrusion strength of the general 20 - 30MPa.

3. Fusion welding -- the tube billet edge transition zone heating to the melting state, welding temperature is more than 1400 DEG C, at this time a portion of a molten metal gasification, and then through the extrusion and extrusion, periodic spark splash in the whole liquid overlapping zone extrusion strength and semi fusion welding is connected to.

ASTM A376 TP347/347H Equivalent Grade

Technical Details/Base Tube Details

Tube Diameter : 20 mm OD Min to 219 mm OD Max.

Tube Thickness : Minimum 2 mm up to 16mm

Tube Material : Carbon Steel, Stainless Steel, Alloy Steel, Corten steel, duplex Steel, Super Duplex Steel, Inconel, High Chrome High Nickle & Incolloy, CK 20 material and some other material.

Fin Details

Fins Thickness : Min. 0.8 mm to Max. 4 mm

Fins Height : Min 0.25” (6.35 mm) To Max.1.5” (38 mm)

Fin Density : Min 43 Fins Per Meter To Max. 287 Fins Per Meter

Material : Carbon Steel, Stainless Steel, Alloy Steel, Corten steel, Duplex Steel and Incolloy.

For a rapid quotation, plz send with following requirement:

Number of pieces,

base tube: Diameter, thickness, length and material specification.

Fins: material specification, type (solid or serrated), height, thickness, spacing, finned length and unfinned sections. Weld prep details if required.

Delivery period required.

Advantages of high-frequency welded finned tubes

1. The installation is simple and economical. The length of high-frequency welding spiral finned tube can reach 6m, reducing the connection points, making the installation economical and fast, and reducing the probability of water leakage at the connection.

2. The maintenance is simple. After the installation of high-frequency welding spiral finned tube, the maintenance is basically unnecessary.

3. High efficiency. High frequency welding of spiral finned tube is the full contact welding between fins and steel pipes. The heat dissipation area is more than 8 times that of smooth tube. The internal is smooth and the internal water flow resistance is small.

4. Long service life, high mechanical strength of the combination of fins and pipes, and tensile strength of more than 200Mpa. The inside and outside of the pipes are all hot-dip galvanized.

Application of Finned Tube in Industries

• Petroleum Industry
• Chemical industry
• Wood industry
• Food industry
• Steel Industry
• Plastic molding industry
• Glycol dehydration units
• Coils for hybrid cooling towers
• Printing Machines
• Production of surface coatings
• Solvent recovery
• Cooling of turbine air intakes
• Textile production
• Greenhouse heaters and breeding
• Tanneries
• Anti-freeze coils for process air
• Paper works