API RP 652-2020 PDF

Full title and description

API RP 652-2020 — Recommended Practice for Field Repair of Aboveground Storage Tanks (repairs and alterations to welded steel tanks storing petroleum and hazardous liquids) — provides guidance, inspection criteria, and accepted repair methods for in-service aboveground storage tanks. The document gives practical procedures for evaluating damage and performing repairs to ensure structural integrity and safe continued service.

Abstract

API RP 652-2020 consolidates accepted industry practices for field repair, alteration, and maintenance of aboveground welded storage tanks used in the petroleum and petrochemical industries. It covers assessment methods, repair techniques (including welding, bolt-up, plate replacement, reinforcement, and partial rebuild), testing and inspection requirements, and documentation needed to verify that repairs meet safety and performance objectives. The recommended practice complements applicable design and fabrication standards to manage aging tanks and unexpected damage while minimizing risk to people, environment, and assets.

General information

• Status: Approved / current (2020 edition)
• Publication date: 2020
• Publisher: American Petroleum Institute (API)
• ICS / categories: 71.040 (Petroleum and related technologies); storage tanks; mechanical engineering
• Edition / version: 2020 (latest published edition for RP 652 as of 2020)
• Number of pages: Typically 40–80 pages (varies by formatting; RP documents are generally in this range)

Scope

This recommended practice provides guidance for the field repair, alteration, and modification of in-service aboveground welded storage tanks that contain petroleum, petroleum products, and other hazardous liquid hydrocarbons. It applies to repair methods for common damage types such as corrosion, dents, cracks, shell and bottom plate failures, nozzle repairs, and seam or weld defects. The RP addresses assessment, selection of repair methods, welding and non-destructive examination (NDE) acceptance criteria, testing (including leak testing and hydrostatic testing), and documentation and quality assurance for repair activities. It does not replace tank design codes but is intended to be used in conjunction with applicable design and fabrication standards and local regulations.

Key topics and requirements

• Procedures for damage assessment and fitness-for-service evaluation of tanks (visual inspection, thickness measurement, corrosion mapping).
• Acceptable repair techniques: weld repair, plate replacement, reinforcement (doubler plates), crack stop-holes, bolted patching, and nozzle repairs.
• Welding qualifications and procedures specific to tank materials and service conditions, including preheat, postweld heat treatment considerations, and filler metal selection.
• Nondestructive examination (NDE) requirements and acceptance criteria for repaired areas (visual, ultrasonic, magnetic particle, liquid penetrant testing).
• Testing and leak-checking methods after repair, including hydrostatic and pneumatic considerations, and safe testing practices.
• Criteria and limits for when field repair is acceptable versus when tank replacement or major rebuild is required.
• Documentation, quality assurance, and reporting requirements for repair records, repair drawings, inspection reports, and material traceability.
• Safety, environmental protection, and procedural controls during repairs (hot work permits, confined space entry, grounding, and vapor control).

Typical use and users

API RP 652-2020 is used by tank owners, operators, inspection and maintenance engineers, tank fabricators, welding contractors, NDE technicians, and regulatory compliance personnel responsible for the continued safe operation of aboveground storage tanks. Typical uses include developing repair procedures, training maintenance crews, preparing inspection and repair reports, and establishing site-specific repair acceptance plans. It is also referenced by consultants performing fitness-for-service assessments and by authorities having jurisdiction when approving repairs.

Related standards

API RP 652 is commonly used alongside and referenced with other standards such as API 650 (Welded Tanks for Oil Storage), API 653 (Tank Inspection, Repair, Alteration, and Reconstruction), API 620 (Design and Construction of Large, Welded, Low-Pressure Storage Tanks), ASME and ASTM material and welding standards, and relevant national/local codes governing pressure vessels, environmental protection, and workplace safety. It complements fitness-for-service guidance (e.g., API and industry FFS documents) and NDE standards.

Keywords

API RP 652, aboveground storage tank repair, tank field repair, welded tanks, corrosion repair, welding procedures, NDE, hydrostatic testing, tank maintenance, petroleum storage

FAQ

Q: What is this standard?

A: API RP 652-2020 is a recommended practice from the American Petroleum Institute providing guidance for field repair, alteration, and maintenance of in-service aboveground welded storage tanks used for petroleum and hazardous liquids.

Q: What does it cover?

A: It covers assessment of damage, acceptable repair methods (welding, plate replacement, reinforcement, patches), welding and NDE requirements, testing procedures, documentation, and safety practices associated with tank repairs. It is intended to be used with applicable design and fabrication codes.

Q: Who typically uses it?

A: Tank owners and operators, inspection and maintenance engineers, welding and repair contractors, NDE technicians, and regulatory or compliance personnel use the RP to plan and execute safe, code-consistent field repairs.

Q: Is it current or superseded?

A: The document referenced is the 2020 edition. Users should verify with the American Petroleum Institute or their organization to confirm whether a more recent edition has been published or if there are errata or interpretations affecting use.

Q: Is it part of a series?

A: Yes. API RP 652 is part of a suite of API tank and storage standards and recommended practices that include API 650 (tank construction), API 653 (inspection and repair), and others addressing design, inspection, and maintenance of storage tanks.

Q: What are the key keywords?

A: Aboveground storage tank, tank repair, field repair, API RP 652, welding, nondestructive examination, corrosion, hydrostatic testing, tank maintenance.