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HITANK-S panels are manufactured using STS 444, a type of material with the best corrosion resistance performance among stainless steel produced and distributed in Korea. The key feature of the panels is that they are assembled with a non-welding bolt assembly method to prevent rusting. Compared to STS 304, STS 444 (Duplex) steel is superior in terms of the time it takes for a fracture to be generated under a repeated load when filling or draining water. Also, existing welded stainless steel (STS 304) water tanks often experience generation of internal rust, which worsens the water quality and reduces the lifespan of the water tank but, in contrast, SRTANK employs the non-welding method and assembles a water tank using only bolts, which makes it an advanced STS water tank product that has completely eliminated any possibility of deterioration and corrosion during welding.

1. Material

  New type of stainless steel with outstanding corrosion resistance

  New STS400 steel material containing molybdenum (Mo)

  Shows powerful corrosion resistance with less generation of rust due to chlorine gas

2. Technique

  Bolt assembly, panel joint technique

  Completely eliminates the issue of rust generation thanks to a non-welding bolt assembly technique

3. Structure

  System that emphasizes external reinforcement

  Minimized internal horizontal reinforcing materials by employing the external frame reinforcement method

  1-3mh: 100% external reinforcement type (no internal reinforcing materials)

  Greater than 3.5mh: Internal and external mixed reinforcement type (no reinforcing materials on the upper section)

  Increased sanitation and convenience in cleaning

4. Comparison of corrosion resistance characteristics

Category Characteristics of STS400 Characteristics of STS300
Impurities Minimum amount having no effect on structural steel Small amount having some effect on structural steel
Processability Fair to weak Excellent
Welding deformation Excellent (less deformation) Weak (significant effect of welding heat)
Corrosion Excellent (no effect on chlorine ion) Weak (vulnerable against chlorine ion)
Magnetism Magnetic material Non-magnetic material
Grain boundary Ferrite stainless steel Ostenitic stainless steel
Stress corrosion Very excellent Weak

5. Chlorine immersion test

- Test solution: 4% chlorine solution, Test period: 50 days


Chlorine immersion test image1

NO RUST (50days)


Chlorine immersion test image2

NO RUST (50days)


Chlorine immersion test image3

Rust occurred(a bit):
after 11day

Rust occurred(entire):
after 19day


Chlorine immersion test image4

Rust occurred(a bit):
after 4day

Rust occurred(entire):
after 10day