API 652: Linings of Aboveground Petroleum Storage Tank Bottoms

Question 1

How do the prior contents of the tank affect the lining process? (API 652-14, Section 7.2)

Answer 1

Prior to abrasive blasting, all hydrocarbon residues such as oil, tar, and grease, must be removed from the area to be lined. Solvent cleaning (see SSPC-SP 1) and high or ultra-high pressure water or steam cleaning, using the proper chemicals, are effective methods of accomplishing complete hydrocarbon removal. Cleaning is typically followed by a fresh water rinse to ensure complete removal of cleaning chemicals.

Question 2

What is the preferred technique for repairing perforations in a steel tank bottom? (API 652-14, Section 7.3)

Answer 2

The repair of perforations of the steel tank bottom shall be by welding of steel patch plates or replacement of bottom plate.