ASTM B111 C70600 Low Finned Tube Copper Nickel Alloy For Heat Exchanger

A low finned tube is a type of heat exchanger tube that has fins on its external surface to increase the overall surface area available for heat transfer. These fins are typically integrally formed from the material of the tube itself during the manufacturing process.

The primary purpose of the fins is to augment the heat exchange efficiency between the fluid inside the tube and the fluid outside it. When fluids flow past the external surface of a finned tube, the increased surface area due to the presence of fins allows more effective heat transfer compared to a plain tube with a smooth surface.

Low finned tubes have fins that are lower in height compared to high finned tubes. The term "low" in this context refers to the height or size of these fins. Lower fin height means that the finned tubes can be used in situations where space and flow characteristics are designed for more moderate increases in surface area and heat transfer effectiveness.

ASTM B111 C70600 Low Finned Tube is a type of heat exchanger tube made from copper-nickel alloy (C70600, also known as 90/10 Cu-Ni), featuring externally enhanced fins to improve heat transfer efficiency. Here’s a detailed breakdown:

Key Features:

1. Material – C70600 (90/10 Cu-Ni):

Material Composition:

Chemical Composition (ASTM B111 C70600)

Notes:

Small amounts of Fe & Mn enhance corrosion resistance in seawater.

Low Pb, S, P ensure weldability & formability.

2. Properties:

Mechanical Properties (ASTM B111 C70600 Seamless Tubes)

A. Wrought (Drawn/Annealed) Tubes

B. Other Key Properties

Density: 8.94 g/cm³

Melting Point: ~1100-1145°C (2012-2093°F)

Thermal Conductivity: ~40 W/m·K

Electrical Conductivity: ~9% IACS (low, due to Ni content)

Corrosion Resistance: Excellent in seawater, brine, and acidic environments.

3. Low Finned Design:

The tube has integral external fins (typically helical or longitudinal) with a lower fin height compared to high-finned tubes.

Increases heat transfer surface area without significantly increasing the tube’s outer diameter.

Improves thermal efficiency in condensers, evaporators, and heat exchangers.

Advantages Over Plain Tubes:

✔ Higher heat transfer efficiency (due to increased surface area).
✔ Compact design (allows smaller heat exchangers).
✔ Resists saltwater corrosion & erosion.

Here are some characteristics of low finned tubes:

• Increased Surface Area**: Compared to plain tubes, low finned tubes provide an increased heat transfer area, which improves the efficiency of heat exchangers.
• Enhanced Heat Transfer**: The increased surface area allows more heat to be transferred between the two fluids involved in the exchange process.
• Compact Design**: Because of their increased efficiency, heat exchangers using low finned tubes can be more compact. This can save space and reduce costs associated with materials and manufacturing.
• Versatility**: Low finned tubes are suitable for both condensation and evaporation processes and can handle a wide range of fluids, including liquids and gases.
• Material Efficiency**: Using finned tubes can allow for reduced material usage for the same heat exchange performance, or enhanced performance without needing to increase the tube size or number.

The main application of ASTM B111 C70600 Low Finned Tube:

1. Marine & Offshore Systems

• Seawater-cooled condensers (shipboard & offshore platforms).
• Desalination plants (multi-stage flash, MED evaporators).
• Heat exchangers for ballast water treatment, cooling systems.
• Oil-cooling systems in marine engines.

2. Power Generation

• Steam surface condensers (thermal & nuclear power plants).
• Auxiliary cooling systems (lube oil coolers, generator cooling).
• Waste heat recovery units.

3. Oil & Gas Industry

• Refinery heat exchangers (cooling hydrocarbon streams).
• Offshore platform cooling systems.
• LNG processing (heat transfer in cryogenic applications).

4. Chemical & Process Industries

• Acid & chemical coolers (due to corrosion resistance).
• Petrochemical processing (condensers, reboilers).
• Brine & saline solution heat exchangers.

5. HVAC & Industrial Cooling

• Chiller tubes (seawater or brackish water cooling).
• Evaporators & condensers in refrigeration.