Standards for the design, manufacture, and installation of riveted steel storage tanks for oil storage have been set by the American Petroleum Industry (API). API inspection companies refer to these standards when conducting tank inspection and assessment.
The 620 and 650 models are now the most prominent tanks on the market, but which is best for you?
What you need from the product will determine the response. Large steel low-pressure storage tanks, typically more significant than 300 feet in diameter, are subject to API 620 regulations for design and manufacture. API Standard 650, on the other hand, is frequently used in carbon, stainless steel, and aluminum tanks found in terminals, distilleries, pipelines, and other processing facilities. Stress and temperature factors are also varied for each. The storage tank model you choose will depend on your individual demands and/or your customers.
For those of you who work in the steel fabrication and tank inspection sector, this article should help to clarify the main distinctions between API Specifications 620 and 650 for holding tanks.
API 620 Standard
Because of its architectural arrangement, you need a raised or flat bottom to store API 620. The tank consists of a single, perpendicular, center point of revolution that is at least 3/16 inches thick in the material. Additional features of API 620 include:
- It is made of aluminum alloys, nickel alloys, and carbon steel.
- The American Society of Mechanical Engineers (ASME), Section 10, requires a welding qualification.
- No outside entity is involved in the mandatory API inspection services.
- The expense of the non-destructive examination is the inspection cost (NDE)
Features of API 620 include:
- It is applied to items with high additional stress, such as cryogenic tanks and liquefied natural gas (LNG).
- It can hold items at lower temperatures and greater pressures of gas or vapor storage).
- Any liquid may be kept in it.
API 650 Standard
API 650 establishes minimal specifications for the design, selection of materials, assembly, and testing of aboveground, open- and closed-top, cylindrical storage tanks of various capacities and dimensions, equivalent to atmospheric pressure. Higher inner tensions are permitted if extra conditions are satisfied. Only tanks that sustain the whole bottom uniformly and tanks used in non-refrigerated operation with a maximum allowable heat of 200 degrees Fahrenheit are covered by API 650. You must have material that is at least 3/16 inches thick. Other features of
API 650 include:
- It comprises aluminum, austenitic duplex alloy steels, and carbon steel.
- The ASME, Section 10, requires a welding certification.
- No outside entity is involved in the mandatory inspection.
- The price of the examination is the price of the NDE.
Some advantages of API 650 are:
- Some of the most famous tanks in the oil business may contain biofuel, oil, gas, chemicals, water, and other liquids.
- It can hold contents at a significantly greater heat (-40 ° F to 500 °F) than the requirements of API 620 but at reduced pressure (maximum 2 12 PSI).
- Any tank size is acceptable.
Which one is the best?
In a nutshell, API 620 allows for storing items at more significant pressure and lower temperatures. In contrast, API 650 only allows for lower pressure and higher temperatures.
After understanding your precise temperature and humidity criteria, you can see that selecting your standard appropriately is essential.…