In the petrochemical industry, the use of storage tank is major as it stores various substances of upstream, midstream, and downstream processes. It is crucial to ensure that these tanks are safe, well-maintained, and compliant with industry standards to avoid any potential risks to human life and the environment. This is where the API standard, API 653, comes into play. API 653 outlines the requirements for maintaining and inspecting aboveground storage tanks (ASTs). This article will explore API 653 in detail and discuss its importance in the storage tank industry.

What is API 653?

API 653 is a set of standards to conduct the inspection, repair, alteration, and reconstruction of aboveground storage tanks (ASTs) used in petroleum and chemical industries. Issued by the American Petroleum Institute (API), API 653 ensures tank owners and operators follow safety measures and maintain their tanks at their highest performance. API 653 guidelines cover several aspects:

  1. Mandatory tank examination requirements
  2. Procedures for tank repairs and alterations
  3. The qualifications required for personnel involved in tank maintenance
  4. The paperwork for inspections and repairs.

The standards of API 653 are crucial to prevent any mishaps that can put the public at risk and cause environmental damage.

What Does API 653 cover?

API 653 covers the standard of tanks with a diameter greater than 30 feet and a height taller than 50 feet. These aboveground storage tanks (ASTs) are created to store large amounts of liquids or gasses, including but not limited to water, petroleum, gasoline, chemicals, and dangerous waste materials. It makes API 653 a necessary standard code for the petroleum and petrochemical industries.

What Are The Critical Components of API 653 (Storage Tank) Inspection?

Some critical components of an API 653 storage tank inspection are mentioned in the following.

1. General Tank Information

The information includes tank specifications, construction, leak identification techniques, and spill control.

2. Bottom, Shell, and Roof of the Tank Components

Tank components inspections must include radiography, magnetic flux scan, vacuum box, tracer gas, visual, ultrasonic (spot), ultrasonic (scan), liquid penetrant, penetrating oil, and magnetic particle.

3. Bottom, Shell, and Roof of the Tank Structure

The tank structures must pass the minimum remaining thickness, minimum required thickness, and maximum corrosion rate. It makes API 653 also includes welding requirements for field-erected tanks.

4. Settlement Evaluations

The examination focuses on how the tank settles in the ground. API 653 assesses the following factors:

  1. Out-of-plane
  2. Rigid body tilting
  3. Uniform
  4. Dish type
  5. Edge settlement, and
  6. Localized dispersions

How Often Is API 653 (Storage Tank) Inspection?

API 653 inspection for petroleum and petrochemical tank inspection
External Inspection of Aboveground Storage Tanks (Credit: Freepik)

A certified API 653 inspector must evaluate the tank’s condition and determine if it is appropriate for ongoing operation. There are two types of aboveground storage tank inspection—internal and external. API 653 external inspection must be done every five years. This interval may extend if the owner chooses to have an ultrasonic thickness (UT) assessment.

The API does not specify the UT method, but automated UT (AUT) techniques can produce accurate data to determine the corrosion rate. The inspection interval can be prolonged up to 15 years if the corrosion rate is known. Otherwise, it remains every five years.

Considering how storage tank maintenance is crucial, API 653 aboveground storage inspector certification program has become one of the most popular certifications. An inspector with API 653 certification should possess extensive knowledge regarding tank inspection and repair and must meet the qualifications stated in API Standard 653, which applies to tank inspection, repair, alteration, and reconstruction.

Prepare your API 653 certification by enrolling in specified API 653 training. With a mixture of lectures, case studies, and discussions, API 653 training by PetroSync can help you acquire theoretical and practical skills in the field of aboveground storage tanks that can be readily applied to your job. Enroll today and take your career to the next level.

How Often Is API 653 (Storage Tank) Internal Inspection?

The internal inspections of API 653 are required every ten years, but the interval may fall shorter based on various factors, including the tank’s age, service, and corrosion rates. API 653 Inspectors then perform non-destructive testing (NDT) techniques that consist as follows:

  • Magnetic Particle Testing (MPT)
  • Radiographic Testing (RT)
  • Liquid Penetrant Testing (LPT)

All of the tests combined help identify any damage, cracks, or corrosion likely to pose a risk to the tank’s usability. Further repairs and modifications that comply with API 653 standards must be done if any defects are detected.

Is Monthly API 653 (Storage Tank) Inspection Mandatory?

In addition to the required five-year external inspection and 10-year internal inspection, monthly assessment under API 653 is recommended to be done by the site owner or operators. These monthly evaluations are for a regulator to review. Any tank failure can be detected earlier by assessing the overall tank condition as comprehensively as possible.

How Does API 653 Regulate The Storage Tank Reconstruction?

Aboveground storage tanks (ASTs) may face relocation or reconstruction for various reasons. The API 653 standards also regulate the requirements for the design, construction, and inspection of the tank placed in the new location or after reconstruction. The tank must meet the current standards of API 653, where the foundation must accommodate its weight and be installed on suitable soil or rocks.

How Does API 653 Regulate The Storage Tank Reparation or Alteration?

API 653 also addresses the repair and alteration of ASTs. Any repair work performed on a tank must be under the supervision of API certified inspector or an experienced tank engineer. Section 9 of API 653 outlines the guidelines a certified inspector must follow when carrying out tasks such as removing or replacing shell plate material, installing a door sheet, repairing or installing a new tank base, and other related tasks.

What Are Some Frequently Asked Question about API 653?

What Are API 653 (Storage Tank) Examination Requirements?

To be eligible for the API 653 exam, a candidate must fulfill one of the following requirements:

1. BS degree or higher in engineering or technology

at least one year of experience supervising or performing inspection activities outlined in API 653.

2. 2-year Associate’s degree or certificate in engineering or technology

must have at least two years of experience in the design, fabrication, repair, operation, or inspection of pressure vessels, with one year of that time spent supervising or performing inspection activities described in API 653.

3. A high school diploma or equivalent

a minimum of three years of experience in the design, fabrication, repair, operation, or inspection of pressure vessels, with one year of that time spent supervising or performing inspection activities described in API 653.

4. No formal education

a minimum of five years of experience in the design, fabrication, repair, operation, or inspection of pressure vessels, with one year of that time spent supervising or performing inspection activities described in API 653.

API 653 certification is not limited to tank inspectors, engineers, and supervisors responsible for ensuring the safety and integrity of ASTs. Maintenance and operations personnel, mechanical engineers, and corrosion engineers can also take this certification. Even though not legally required, API 653 certification is frequently requested by employers and regulatory agencies as evidence of expertise.

If you want to take the API 653 certification, learning from API Body of Knowledge and enrolling in API 653 training by PetroSync should be your game-changer moves. API is widely known for its continually evolving standards, as new information and techniques are added every year.

With our 5-day API 653 – Tank Inspection, Repair, Alteration, and Reconstruction, you can learn relevant course materials and real-world examples to help you get a deeper and more long-term understanding. With 90% of all PetroSync’s training confirmed to run as scheduled, our program is designed to fit seamlessly into your work schedule at the earliest. Claim your spot!

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