Corrosion risk planning – 2 – Above ground storage tanks – oil and gas- PART 2

 Above ground storage tanks – PART 2

9.    Splash plate

      • corrosion at welds
      • atmospheric corrosion
      • coating damage, if applicable
      • pitting due to chloride salt deposition in marine environment

10.    Spiral staircase

      • corrosion at welds of individual bars and critical joints to the tank
      • coating damage and delamination
      • cracks near welds
      • uniform corrosion at exposed surface near delamination
      • galvanic corrosion near weld/staircase/tank interface due to dissimilar alloys

11.    Manometer

      • corrosion of screws, nuts, and bolts used for attachment
      • possible moisture penetration in case of cracks due to improper handling

12.    Manhole

      • Internal corrosion due to water either as a moisture or as storage product
      • External coating damage due to moisture penetration, dust, rainfall, UV radiation
      • Coating damage at fixtures and edges
      • galvanic corrosion at nuts and bolts due to dissimilar alloys
      • atmospheric corrosion at area where coating is delaminated
      • galvanic/atmospheric corrosion of and at hinges, corrosion product buildup

13.    Drain valve

      • galvanic corrosion in case of dissimilar metals. If valve is of brass, surrounding steel will corrode
      • pitting in case of stagnated water with chloride salts

14.    Concrete drain

      • moisture ingress in concrete
      • possible corrosion of reinforcements especially if any remain exposed

15.    Main inlet

      • Corrosion at welds
      • Crevice corrosion

16.    Automatic tank gauge

      • corrosion at fixtures

17.    Secondary inlet

      • Corrosion at welds
      • Crevice corrosion

18.     Bund wall

      • Concrete degradation due to moisture ingress.
      • reinforcement corrosion at exposed areas
      • Possible biological contamination in case of stagnant undrained water

19.    Pipe bends

      • internal erosion corrosion at the bends
      • external coating damage
      • atmospheric corrosion at point of coating delamination

20.    Floor plates

      • soil side corrosion
      • Insufficient CP
      • coating damage and locoalized corrosion, if coating is used for underside
      • underdeposit corrosion

21.    Foundation settlement

      • soil side corrosion
      • rain water absorption and migration to tank bottom
      • loosening of soil
      • uneven foundation, tilting of tank, preferential corrosion on one side

22.    Roof

      • External atmospheric corrosion
      • coating damage
      • corrosion at welds
      • localized corrosion at points of stagnation
Would love to hear your experience and comments!

Click here for part 1!

😀Happy learning!😀

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