API Std 650 flat-bottom tanks maximum liquid level

Crack treatment of API Std 650 flat-bottom tanks weld area: find out the crack tip with ray or ultrasonic flaw detection, drill cut-off holes at both ends of the crack with the cut-off method, the hole depth is slightly greater than the crack depth, or groove (crack stop groove) is made by angle grinder at both ends of the crack, shovel and grind the whole crack, and grind it into a suitable groove; use radiographic inspection and dye detection to verify that the crack has been completely excavated, and finally repair welding.

In the process of API Std 650 flat-bottom tanks steel transportation, enterprises often use railway transportation, highway transportation, water transportation and other ways to transport. According to the cargo owner's requirements on the timeliness of the goods and the different transportation routes, our company will choose API Std 650 flat-bottom tanks different modes of transportation. According to the specific needs of customers, or specify the mode of transportation.

Preheating should be performed by heating and maintaining this heat in appreciable lengths of the joint to be welded, preferably using a strip burner with a mild flame rather than a harsh flame such as that from a cutting torch. Electrical strip heaters are available and have been found to be satisfactory. The preheat of 300°F should be checked with a temperature-sensitive crayon, or similarly accurate means, so that the steel 4 in. (or four times the API Std 650 flat-bottom tanks plate thickness, whichever is greater) on each side of the joint will be maintained at the minimum preheat temperature. Ring burners or heaters are recommended for nozzle and manway welds. At no time during the welding should the base metal fall below a temperature of 300°F.