How to limit the release of liquid contents from API Std 650 welded storage tanks

The seal of floating roof API Std 650 welded storage tanks is a device used to reduce the evaporation loss of the storage liquid in the annular space between the tank wall and the outer ring plate of the floating roof. The common sealing forms include mechanical seal, elastic filling seal, lip seal and secondary seal. No matter what kind of seal, the seal must be combined with the floating roof effectively to reduce the evaporation loss of the liquid in the floating roof.

If customers have any difficult problems during use of the steel materials, they can contact the company's after-sales service department to feedback the existing problems. The after-sales department will reply as soon as possible to ensure that each customer has a good after-sales experience. Under special circumstances, the after-sales service department will start the problem-solving process, and the engineers in charge of the area will quickly follow up to solve the problem.

Preheat Treatment
Many laboratory tests have shown preheat treatment of carbon steel to 300°F-400°F to be the equivalent of the post-heat treatment at no less than 1100°F insofar as the physical properties of the weldment are concerned.40,41 Some tests have indicated a slight advantage of the post-heat treatment. Most of the tests have been made on plates 3/4 in. - 1 in. thick; results must be viewed with caution if preheating is applied appreciably beyond this thickness range. However, for all practical purposes, improvement resulting from preheating is sufficiently well established so that preheat should be considered for field fabrication of API 620 crude oil tank plates over 3/4-in. thick whenever toughness of the tank API Std 650 welded storage tanks is highly desired and the thermal post-heat treatment is impractical.

This standard applies only to API 650 tank API Std 650 welded storage tanks whose entire bottom is uniformly supported and to API 650 tank in non-refrigerated service that have a maximum design temperature of 93°C (200 °F) or less.