API Std 653 pdf download.Tank Inspection, Repair, AIlteration, and Reconstruction
1.1.1 This standard covers carbon and low alloy steel tanks built to API Standard 650 and its predecessor API 12C. This standard provides minimum requirements for maintaining the integrity of welded or riveted, nonrefrigerated, atmospheric pressure, aboveground storage tanks after they have been placed in service. It covers the maintenance inspection, repair, alteration, relocation, and reconstruction of such tanks. 1.1.2 The scope is limited to the tank foundation, bottom, shell, structure, roof, attached appurtenances, and nozzles to the face of the first flange, first threaded joint, or first weld- ing-end connection. Many of the design, welding, examina- tion, and material requirements of API Std 650 can be applied in the maintenance inspection, rating, repair, and alteration of in-service tanks. In the case of apparent conficts between the requirements of this standard and API Std 650 or its predeces- sor API 12C, this standard shall govern for tanks that have been placed in service. 1.1.3 This standard employs the principles of API Std 650; however, storage tank owner/operators, based on consider- ation of specific construction and operating details, may apply this standard to any steel tank constructed in accor- dance with a tank specification. 1.1.4 This standard is intended for use by organizations that maintain or have access to engineering and inspection personnel technically trained and experienced in tank design, fabrication, repair, construction, and inspection. 1.1.5 This standard does not contain rules or guidelines to cover all the varied conditions which may occur in an existing tank. When design and construction details are not given, and are not available in the standard to which the tank was origi- nally constructed, then details that will provide a level of integrity equal to the level provided by the current edition of API Std 650 must be used. 1.2 COMPLIANCE WITH THIS STANDARD The owner/operator has ultimate responsibility for com- plying with the provisions of this standard. The application of this standard is restricted to organizations that employ or have access to an authorized inspection agency as defined in 3.4. Should a party other than the owner/operator be assigned certain tasks, such as relocating and reconstruct- ing a tank, the limits of responsibility for each party shall be defined by the owner/operator prior to commencing work. 1.3 JURISDICTION If any provision of this standard presents a direct or implied confict with any statutory regulation, the regulation shall govern. However, if the requirements of this standard are more stringent than the requirements of the regulation, then the requirements of this standard shall govern. 1.4 SAFE WORKING PRACTICES An assessment shall be made of the potential hazards to which personnel may be exposed when conducting internal tank inspections, making repairs, or dismanting tanks. Pro- cedures shall be developed according to the guidelines given in API Standard 2015, Recommended Practice 2016, and Publication 2217A that will include safeguard for per- sonnel health and safety, prevention of accidental fires and explosions, and the prevention of property damage. Special procedures may need to be developed for certain activities described in this standard that are not fully covered by the referenced API publications; for example, safety pre- cautions for personnel accessing floating roof tanks that are in service, or gas freeing the bottom side of a tank.
For the purposes of this standard,the following definitions apply: 3.1 alteration: Any work on a tank involving cutting, burming, welding, or heating operations that changes the physical dimensions and/or configuration of a tank. Typical examples of alterations include: a. The addition of manways and nozzles greater than 12-in. nominal pipe size (NPS). b. An increase or decrease in tank shell height. 3.2 applicable standard: The original standard of con- struction, such as API standards or specifications or Under- writer Laboratories4 (UL) standards, unless the original standard of construction has been superseded or withdrawn from publication; in this event, applicable standard means the current edition of the appropriate standard. See Appen- dix A for background on editions of API welded storage tank standards. 3.3 atmospheric pressure: Used to describe tanks designed to withstand an internal pressure up to but not exceeding 21/2 lbf/in.2 gauge. 3.4 authorized inspection agency: One of the follow- ing organizations that employ an aboveground storage tank inspector certified by API.