Tan Long Factory Standard Technical Specifications Matrix
1. Flooded Evaporation Thermodynamics & Brine Flow Dynamics
Tan Long herringbone coils operate under flooded evaporation principles:
• 100% of internal tube surfaces are continuously flooded with liquid refrigerant at -15°C to -18°C.
• Heavy brine agitators circulate salted brine continuously across outer tube surfaces at overall heat transfer coefficients K of 550 to 750 W/m².K.
• Boiling refrigerant vapor bubbles rise rapidly into top suction headers, returning dry gas to compressor racks.
2. ASTM A123 Full Hot-Dip Galvanizing Process
After precision bending and robotic welding on structural jigs, completed coil assemblies undergo pickling acid wash and are immersed in a 450°C molten zinc bath. A durable >80-micron metallurgical zinc alloy layer forms an impervious barrier against electrochemical corrosion.
3. Essential Cold Source for Offshore Fishing Fleets
Commercial block ice is irreplaceable for long-haul offshore fishing vessels. Tan Long herringbone coils produce high-density 50kg and 100kg ice blocks with slow melt rates, preserving tuna, mackerel, and squid across extended sea voyages.
Competitive Advantages & Market Comparison Matrix
Technical comparison between genuine Tan Long refrigeration equipment manufactured at Duc Hoa 1 Industrial Park versus substandard market alternatives:
Tan Long Equipment Advantages
- ✓ Heavy seamless steel pressure pipe, fully hot-dip galvanized inside and out after bending
- ✓ Staggered tube geometry reduces hydraulic friction, generating uniform vortex brine circulation
- ✓ 100% water-tank immersion pneumatic leak testing at 25 bar nitrogen prior to factory release
- ✓ Proven track record equipping hundreds of commercial ice plants across fishing ports nationwide
Drawbacks of Manual / Used Imported Systems
- ✗ Artisanal workshops use cheap seamed pipe with flattened bends that choke refrigerant flow
- ✗ Cheap anti-rust paints flake off within weeks of brine immersion, causing severe rust perforation
- ✗ Improper hydraulic design causes uneven brine flow, leaving outer ice cans unfrozen
- ✗ High risk of catastrophic ammonia leaks into brine tanks ruining entire ice harvests
Frequently Asked Questions (FAQs) by Engineers & Investors
Q1: Why do Tan Long herringbone coils freeze block ice faster than locally fabricated coils?
Tan Long calculates precise tube pitch matching agitator cross-flow velocities and integrates an oversized suction accumulator. The coil remains 100% wetted with liquid refrigerant while protecting compressors from liquid slugging.
Q2: What is the optimal brine concentration to prevent evaporator icing?
NaCl brine concentration should be maintained at 21% to 23% (20 to 22 deg Baume). At this concentration, the freezing point of brine is depressed to -18°C to -21°C, optimizing thermal transfer to ice cans without risking slush freeze-up on coil surfaces.
