API 650 only covers tanks that support the whole bottom evenly and tanks in non-refrigerated service that have a maximum design temperature of 200 degrees F. If additional requirements are met, higher internal pressures are allowed. It can store contents at a higher pressure (maximum 15 pounds per square inch (PSI) of gas or vapor storage) and lower temperature (-325 degrees F to 250 degrees F) than API 650.ĪPI 650 sets minimum requirements for the design, material, construction, and testing for aboveground, open and closed-top, cylindrical steel storage tanks in different capacities and sizes, roughly equating to the pressure of the atmosphere (not greater than the weight of the roof plates).It is used for products that have high internal pressure such as liquefied natural gas (LNG) and cryogenic tanks.The inspection cost is the cost of the non-destructive inspection (NDE).There is a required inspection, no third party.A Welding Certification is stipulated by the American Society of Mechanical Engineers (ASME), Section 10.It is constructed from carbon steel, austenitic stainless steel, and nickel alloys (low temperature only).The tank has a single, vertical, central axis of revolution with a minimum material thickness of 3/16 inches. The design configuration of API 620 requires that you have an elevated or flat bottom on which to store it. For the complete API Standard 650, 10th Edition, March 2007, click here. If you require the complete API Standard 620, 10th Edition, February 2002, click here. Your choice of model will depend on you and/or your client’s particular needs.
Both have different pressure and temperature parameters as well. By contrast, API Standard 650 is typically used for carbon, stainless steel and aluminum tanks located in terminals, refineries, pipelines and other process facilities. The answer depends on what you require out of the product.API 620 regulates the design and manufacture of large steel low-pressure storage tanks, usually larger than 300 feet in diameter. The most popular tanks available on the market today are the 620 and 650 models, but which is right for you? The American Petroleum Industry (API) has established standards for the design, fabrication, and construction of welded steel storage tanks for storing oil.