How terrible foundation settlement occurred | We adopt flexible design
A Garner manager said:"After the completion of our 100 thousand cubic floating roof storage tank, its foundation settlement occurred. Deformation and unstable of the upper structure of the tank leading to the failure of the tank can not meet requirements.”
Background
As the most important equipment in reserve tank, in recent years, with the scale of domestic crude oil, refined oil reserve continues to increase, the design and construction technology of storage tank is also rapidly increasing. The amount of steel and floor area of large storage tanks is lower than that of small capacity storage tanks, which can effectively save investment and construction land. Therefore, large scale is the general trend of the construction of storage tanks.
Consider from construction cost and operating costs of reserve tank, many large oil reserve bases living along the coast at present, and many are built in soft soil foundation of land reclamation. The difference and complexity of regional geological conditions also cause the problem of uneven settlement.
Main harm of the uneven settlement
When the amount of uneven settlement exceeds the standard, the main harm of that is:
- The geometry deformation of tank body makes a gap between the tanks, resulting in a high concentration of oil and gas space.
- With the influence of the tank bottom deformation, coupled with stress increasing, the bottom plate weld crack resulting in brittle failure in the end.
These problems have brought great security risks and management problems to oil production. Therefore, conduct a comprehensive monitoring to uneven settlement and timely correction and adjustment become an important part of the management of storage tanks.
Flexible design in the inlet and outlet pipeline of large storage tank
In the engineering design, it should be as far as possible to adopt flexible connection between pipeline and tank wall, avoiding rigid connection. The metal hose is mainly composed of corrugated pipe, net sleeve and joint, which has the function of shock resistance, bending, and absorption.
- Corrugated pipe is the main body of the metal hose and it is a kind of cylindrical thin shell with transverse ripple. Under the effect of axial tension or pressure, it can be extended or shortened.
- Net sleeve, which is made of stainless steel wire or coil strip according to certain parameters, play the role of strengthen and shield. The net sleeve is the main pressure part which is installed in the pressure pipe.
- Effect of joints at both ends of the corrugated metal hose is connecting the net sleeve to the corrugated pipe. At the same time, the joint is also a component connected between metal hose and other pipe fittings or equipment.
TICO storage tank
After a large number of data analysis, TICO affirm the necessity of flexible design in the inlet and outlet pipeline. At the same time, we consider other factors, such as the seismic fortification intensity, site classification, process layout, working temperature, transport medium, climatic conditions, pipe diameter and maximum displacement. Finally, not only meet the lateral displacement of flexible pipe fittings, but also meet the axial displacement generated.
