For outdoor underground fire water tanks, made of spiral-welded submerged-arc welded steel pipes, is it necessary to apply rust prevention treatment to the inner wall?
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Outside, for use in underground fire water tanks; the tanks remain filled with water at all times. Only the outer wall was painted; nothing was done to the inner wall. Will it rust through over time?
If there is always water in the tank, the inner walls do not need to be treated for corrosion prevention
I can see that the inner wall of the pipe is already rusty
The pool probably won’t stay at full water level for long; corrosion at the interface between water and air as well as on the upper part will be quite severe, so effective protection measures should be taken.
Preservation is generally not required, unless special requirements exist.
Preservation is generally not required, unless special requirements exist.
Of course there is corrosion; there are many impurities in the circulating water. However, the inner wall does not require anti-corrosion treatment. It is recommended to use seamless pipes
Since it hasn’t been put into official use yet, I went in to take a look after the water was drained from the pool. The pipes are placed below the water level; the inner walls haven’t been treated, and the outer walls have a little paint on them, but they’re all rusted
For such pipes, even if the inner wall is coated for corrosion protection, the welds at the pipe joints cannot be protected against corrosion internally.
The material and wall thickness of pipes need to be determined based on the corrosion rate of the medium. For fire protection pipes, using spiral-welded pipes is perfectly fine; rusting is not a problem as long as the corrosion margin meets the required standards.
The cost of internal anti-corrosion is high, so it’s not necessary.