large fuel storage tank welds attaching nozzles
Prefabrication requirements for large fuel storage tank, large vertical storage tanks:1. The machined surface of the edge of the steel plate should be smooth, and there should be no defects such as slag inclusion, delamination, cracks, etc., and the surface hardened layer produced by the flame cutting groove should be removed.2. Dimension deviation after steel plate processing: the deviation of plate width is less than 1.5 mm, the deviation of plate length is less than 2 mm, and the difference between diagonals is less than 3 mm.
Standard Hydrostatic and Pneumatic TestsAfter erection is completed and stress relieving, radiographic examinations, or other similar operations, as may be required, are performed, each tank shall satisfactorily pass a series of hydrostatic and pneumatic tests as prescribed in 7.18.2 through 7.18.6. Whenever a solution film is specified in this section to be applied to welding, linseed oil or another equivalent material for disclosing air leakage may be substituted. In freezing weather, linseed oil or a similarly suitable material shall be used.The attachment welding around all openings and their reinforcements in the walls of the API 620 tank shall be examined by the magnetic-particle method both inside and outside the tank large fuel storage tank. When the underside of a tank bottom rests directly on the tank grade (and is not accessible after erection), such examination of welding on the underside of the bottom and subsequent air testing may be omitted.
This specification, in conjunction with API 650 Standard, prescribes minimum standards for the large fuel storage tank design, supply, fabrication, erection, and testing of field erected welded steel storage tanks complete with accessories as specified herein and as shown on attached Datasheets and/or Drawings.
In December of 2015, our regular India customer sent us an inquiry for large fuel storage tank pipe. The inquiry requires no negative tolerance in both pipes’ outer diameter and pipe wall. After two weeks’ discussion, he put the order of 275 tons to us. The pipes are finished within just one month. Our customer come to our factory to inspect the quality and tolerance, all the products are well meet his demand. The pipes are arriving to Nhava Sheva port, customer is very happy with our products and service during the process.