API 650 SUG II tanks tank-bottom reinforcing plate
Inspection of Butt-welds in PipingButt-welds in piping and in API 650 SUG II tanks pipe fittings within the limitations of 1.3.2 (including the annular space of double- wall tanks) shall be inspected in conformance with API 620 oil tank standard Q.7.7.2 through Q.7.7.6. Longitudinal welded joints in piping that contains liquid shall be completely radiographed except for manufactured pipe welded without filler metal, 12 in. or less in diameter, which is tested hydrostatically or by eddy current to ASTM requirements.
All edges of the inner wall of the API 650 petroleum storage tank to be lined or coated must be rounded and flat to a minimum radius of 3mm. The API 650 SUG II tanks internal welding seam must be completely sealed welding, with a smooth surface and no air holes, air pockets and local protrusions. Remove welding spatter. As specified in API 650 petroleum storage tank design drawings, the seller must perform additional surface treatment.
The process parameters should be strictly controlled in sand blasting of API 650 SUG II 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.
