API Std 650 unanchored liquid-storage tanks greater than 200 ft in diameter

Treatment of API Std 650 unanchored liquid-storage tanks welding defects:
1. Lack of fusion: once found, it should be shoveled and grinded off before re welding.
2. Incomplete penetration: over standard defects shall be removed and re welded. When welding on both sides, the shallow side of the groove can be grinded and shoveled to expose the welding root on one side, and then the welding is repaired.
3. Slag inclusion: over standard defects shall be removed and re welded.
4. Crater: weld to full after grinding.
5. Air hole: if the internal air hole exceeds the standard, it shall be welded again after being removed by grinding shovel, and the surface air hole shall be removed by grinding wheel and then repaired.

Design of Reinforcement for Single Openings in Tank Walls
The 20 in. x 29 in. obround manhole shown in Figure F-5 is located in solid plate in the sidewall of a cylindrical storage tank 45 ft in diameter in an area where the thickness of the wall plate, tw, is 1/2 in. No corrosion allowance is required. The total internal pressure, Pl + Pg, at the horizontal centerline of the opening is 27.5 lbf/in.2 gauge. The thickness of the wall plate, t, required by 5.10.3 for the latitudinal unit forces, T2, acting at this level is 0.485 in. The manhole neck is fabricated by welding from 3/8 in. plate. The materials in the API 620 tank wall, the manhole neck, and the reinforcing pad conform to ASTM A516 Grade 60. The joints in the welded steel storage oil tank wall and the longitudinal joint or joints in the manhole neck are double-welded butt joints, spot radiographed in accordance with 7.16 and 7.17.

The characteristics of the API Std 650 unanchored liquid-storage tanks internal floating roof structure of API 650 petroleum storage tanks: the inner floating roof or inner floating plate refers to the floating roof that floats on the liquid surface of the oil tank with the oil and liquid up and down. The API Std 650 unanchored liquid-storage tanks inner floating roof is used to cover the liquid. The surface is currently recognized as the most ideal and most economical and practical way to reduce oil evaporation loss.

The company operates on the principles of fairness, objectivity, science, pragmatism and integrity. The management treats people with courtesy, takes sincerity as the standard management, dares to open up, unites and advances, carries on the past and makes unremitting efforts, seizes the good trend of economic development, strengthens exchanges with peers, makes friends with all walks of life, keeps pace with the times and creates greater brilliance of the enterprise, and makes its own contribution to the prosperity and development of the steel industry.

Since its establishment, the company has participated in several key railway and highway projects. After years of development, the company’s API Std 650 unanchored liquid-storage tanks domestic market has been exported to more than a dozen provinces and cities including Kunming, Shenzhen, Hunan, Sichuan, Shanghai, Nanjing, Heihe, Jilin, Inner Mongolia, and Xinjiang . International trade is exported to Kazakhstan, South Korea, Vietnam, South Africa and many other countries, and has been well received by customers.