API 650 open-top tanks configuration

The hardness of the welds contacting these environments, including the heat-affected zones, shall be considered. The weld metal and adjacent heat-affected zone often contain a zone of hardness that is well in excess of a value of 22 on the Rockwell C scale and could be expected to be more susceptible to cracking than would unwelded metal. Any hardness criteria shall be a matter of agreement between the Purchaser and the API 650 open-top tanks manufacturer and shall be based on an evaluation of the expected hydrogen sulfide concentration in the product, the possibility of moisture being present on the inside metal surface, and the strength and hardness characteristics of base metal and weld metal.

API 650 vertical tanks meet American Petroleum Industries (API) standards in design, material, fabrication, and testing of aboveground welded steel API 650 open-top tanksstorage tanks for use in industrial applications.

The process parameters should be strictly controlled in sand blasting of API 650 open-top tanks. The working pressure of abrasive chamber is between 0.5 and 0.6a, and the outlet pressure of air compressor shall not be lower than 0.6 WPa. According to the test results, the distance between nozzle and workpiece shall be controlled at 80 - 200 mm and spraying angle of 30 ~ 75°is appropriate.