API standard 650 ground supported flat-bottom tanks equipped with a fixed roof

In this project a cylindrical tank 75 ft in diameter is designed for an internal pressure of 0.5 lbf/in.2 gauge in the vapor space. The plate material is ASTM A131 Grade B steel for thicknesses of 1/2 in. and less.
The top course of the butt-welded cylindrical sidewall is 1/4 in. thick. The tank API standard 650 ground supported flat-bottom tanks roof is a conical shape with a 2:12 slope and a 1/4 in. thickness with single full-fillet welded lap joints. The maximum design liquid level is 6 in. below the plane of juncture of the roof and sidewall.

Compared with the fixed roof API 650 oil storage tank without API standard 650 ground supported flat-bottom tanks floating roof, there is no evaporation space. In principle, this eliminates the so-called "large breathing loss". Evaporation not only causes the loss of product quantity, but also affects the quality of API standard 650 ground supported flat-bottom tanks product and pollutes the environment.

Generally, the building area temperature of the API standard 650 ground supported flat-bottom tanks should be considered before the tank design and construction. The temperature in the API standard 650 ground supported flat-bottom tanks building area is closely related to the evaporation loss, energy loss, storage tank materials and the selection of detection instruments, or has a direct impact on the storage cost of the storage liquid. For the same medium, the higher the air temperature and the longer the duration, the higher the material temperature in the API standard 650 ground supported flat-bottom tanks, the higher the corresponding pressure and the more volatile loss.