Linings of Aboveground Petroleum Storage Tank Bottoms

API RECOMMENDED PRACTICE 652 FIFTH EDITION, MAY 2020

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Copyright © 2020 American Petroleum Institute

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Foreword

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Contents

Page

1. Scope 1

2. Normative References 1

3. Terms and Definitions 2

4. Corrosion Mechanisms 6

   1. General 6

   2. Chemical Corrosion 6

   3. Concentration Cell Corrosion 6

   4. Oxygen Cell Corrosion 7

   5. Galvanic Cell Corrosion 7

   6. Microbiologically Influenced Corrosion (MIC) 7

   7. Erosion-corrosion 7

   8. Fretting-related Corrosion 8

   9. Generalized vs Localized (Pitting) Corrosion 8

   10. Stress Corrosion Cracking 8

   11. Internal Corrosion Mechanisms 8

5. Determination of the Need for Tank Bottom Lining 9

   1. General 9

   2. Linings for Corrosion Protection 9

   3. Tank Corrosion History 9

   4. Tank Foundation 10

6. Tank Bottom Lining Selection 10

   1. General 10

   2. Inorganic Zinc/Zinc Silicate (IOZ) 11

   3. Thin-film Tank Bottom Linings 12

   4. Thick-film Unreinforced Tank Bottom Linings 13

   5. Reinforced Thick-film Tank Bottom Linings 14

   6. Circumstances Affecting Lining Selection 16

   7. Selecting Internal Linings for Tanks Storing Alternate Fuels 18

7. Surface Preparation 20

   1. General 20

   2. Pre-cleaning 21

   3. Bottom Repair and Subsequent Weld and Component Preparation 21

   4. Surface Cleanliness 21

   5. Surface Profile or Anchor Pattern 22

   6. Air and Abrasive Cleanliness 22

   7. Removal of Salts 22

   8. Removal of Dust 22

8. Lining Application 22

   1. General 22

   2. Guidelines for Lining Application 23

   3. Temperature and Humidity Control 23

   4. Lining Thickness 23

   5. Lining Curing 23

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      Contents

      Page

9. Inspection 24

   1. General 24

   2. Qualification of Inspection Personnel 24

   3. Recommended Inspection Parameters 24

10. Evaluation, Repair, and Replacement of Existing Linings 25

    1. General 25

    2. Evaluation Methods 25

    3. Evaluation Criteria for Linings 25

    4. Evaluating Serviceability of Existing Linings 26

    5. Determining the Cause of Lining Degradation/Failure 26

    6. Lining Repair and Replacement 26

11. Maximizing Lining Service Life by Proper Material Selection and Specification 27

    1. General 27

    2. Lining Material Selection 28

    3. Written Specification 28

12. Health, Safety, and Environmental 28

    1. General 28

    2. Tank Entry 29

    3. Surface Preparation and Lining Application 29

    4. Manufacturer’s Safety Data Sheets 29

Bibliography 30

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Linings of Aboveground Petroleum Storage Tank Bottoms

1. Scope

   
   

   This recommended practice (RP) provides guidance on achieving effective corrosion control in aboveground storage tanks by application of tank bottom linings. It contains information pertinent to the selection of lining materials, surface preparation, lining application, cure, and inspection of tank bottom linings for existing and new storage tanks. In many cases, tank bottom linings have proven to be an effective method of preventing internal corrosion of steel tank bottoms.

   
   

   The intent of this RP is to provide information and guidance specific to aboveground steel storage tanks in hydrocarbon service. Certain practices recommended herein may also be applicable to tanks in other services. This RP is intended to serve only as a guide. Detailed tank bottom lining specifications are not included.

   
   

   Because of the wide variety of service environments, this RP does not designate specific tank bottom linings for

   every situation.

   
   

   NACE No.10/SSPC-PA 6 and NACE No. 11/SSPC-PA 8 are industry consensus standards for installation of linings on tank bottoms and vessels. They are written in compulsory language and contain specific criteria intended for use by persons who provide written specifications for tank and vessel linings. These documents should be given consideration when designing and installing a lining system for steel bottom tanks.

   
   

2. Normative References

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any addenda) applies.

API Bulletin 939-E, Identification, Repair, and Mitigation of Cracking of Steel Equipment in Petroleum Refineries and Petrochemical Plants

API Recommended Practice 651, Cathodic Protection of Aboveground Petroleum Storage Tanks

API Standard 653, Tank Inspection, Repair, Alteration, and Reconstruction

API Standard 2015, Requirements for Safe Entry and Cleaning of Petroleum Storage Tanks

ASTM D4285,1 Standard Test Method for Indicating Oil or Water in Compressed Air

ASTM D4414, Standard Practice for Measurement of Wet Film Thickness by Notch Gages

ASTM D4940, Standard Test Method for Conductimetric Analysis of Water Soluble Ionic Contamination of Blasting Abrasives

ASTM E96, Standard Test Methods for Water Vapor Transmission of Materials ASTM G9, Standard Test Method for Water Penetration into Pipeline Coatings NACE 37519,2 Corrosion Data Survey—Metals Section

1 ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, Pennsylvania 19428-2959, www.astm. org.

2 NACE International (formerly the National Association of Corrosion Engineers), 15835 Park Ten Place, Houston, Texas 77084, www.nace.org.

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