oil floating roof tank storage tank welded pipe joint efficiencies

The safety inspection of atmospheric storage tank, oil floating roof tank storage tank is divided into external inspection, internal and external inspection and comprehensive inspection. External inspection shall be conducted at least once a year, internal and external inspection shall be conducted at least once every three years, and comprehensive inspection shall be conducted at least once every six years. The safety inspection of large atmospheric storage tanks, oil floating roof tank storage tank requires special attention: the parts where the liquid level often fluctuates, the parts that are susceptible to corrosion, and the parts that are deformed and worn during use should be checked.

The oil floating roof tank storage tank stiffener ring and backing strip (if used) are primary components, and they shall comply with the requirements of API 620 storage steel tank Q.2.1. The stiffener rings may be fabricated from plate using an intermittent weld on alternating sides between the web and the flange.
Except for aluminum or stainless steel tanks, all fillet welds shall consist of a minimum of two passes. The ends of the fillet welds shall be 2 in. from the rat hole (see Figure Q-1), and these welds shall be deposited by starting 2 in. from the rat hole and welding away from the rat hole. An acceptable alternative to the detail that includes stopping fillet welds 2 in. short of the rat hole would be to weld continuously through the rat hole from one side of the stiffener to the opposite side. All craters in fillet welds shall be repaired by back welding.

This specification, in conjunction with API 650 Standard, prescribes minimum standards for the oil floating roof tank 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 oil floating roof tank 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.