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Home / IS-Bauen / Projects / Plants / Tanks / Flat bottom |
The temperature of the tank filling is 150 °C due to a heating installation at the bottom of the tank. The tank is isolated and was certified for atmospheric pressure only. Due to changing the working conditions, the tank filling (oil with a dead load of 9,2kN/m3) must now be protected with a N2-covering to avoid O2-accumulation. To minimize the loss of N2-volume, the tank had to be sealed above the oil-filling. The internal pressure or suction is limited by the use of Kito-vacuum pressure control valves between -5,0mbar (suction) and +10.0mbar (pressure).
Due to the changed working conditions, verifications for buckling for each tank segment with individual thickness were led. We also checked the new bearing conditions (lifting up) caused by the internal pressure acting upwards againsts the roof plates and the wind suction above. The radial tension stresses in the roof plates due to the lifting loads are equilibrated by the roof edge-ring, which had to be reinforced.
The last revision of the tank was ten years old and the minimum thicknesses of the shell plates could not be given. So in the statical calculation we also had to determine the minimum thicknesses to be guaranteed.
