Treatment of deformation in the bottom plate of welded storage tanks
Thread Content
When manufacturing custom storage tanks on-site, how should deformation after welding the tank bottom plate be addressed? There is a 5 cm gap between the bottom plate and the foundation – are there any specifications or technical standards that can be referred to?
According to GB50128, after welding the bottom of the tank, the depth of local uneven deformation shall not be greater than 2% of the deformation length, and must not exceed 50 mm. The inclination of the single-sided tank bottom should not exceed 40 mm.
The storage tank has now been constructed; how should the gap between the bottom plate and the foundation be dealt with?
Personally, I think there’s no need to deal with the gap between the floor and the foundation, as long as it’s not too large.
If the bottom plate deforms beyond the standard, it must be addressed. Because as materials are charged and discharged, pressure changes, the bottom of the tank will be damaged very quickly.
It depends on the size of your storage tank. We used to cut open the areas where deformation was significant in order to relieve stress, and we would fill the bottom plate with sand; this wasn’t in accordance with the standards – it was an approach we came up with on our own. However, our tanks are of the atmospheric pressure fixed-roof type, so the operational requirements aren’t very high.