What are the factors that lead to the damage of FRP storage tanks?

The factors leading to the damage of FRP storage tanks are:

① Open-air environment. So far, the hydrochloric acid storage tank has been waterproof for 9 years. Before 2007, anti-aging measures such as sun protection and heat preservation were not taken, and the tank was directly exposed to the open air. Ultraviolet rays in the sun will degrade the resin and reduce its strength. In addition, wind, rain and frost also have a certain erosion effect on the surface of FRP. Under the action of water, the resin is degraded, so that the glass fiber in FRP is eroded and dissolved under the action of microcracks and interfaces, which accelerates the aging process and reduces the strength.

② Temperature difference change. When the storage tank is exposed to direct sunlight, thermal expansion and cold contraction will lead to FRP fatigue. The temperature difference of glass and the remaining gaps and bubbles in steel are easy to expand under the condition of temperature difference change, which accelerates the destruction of the structure and reduces the strength.

③ Stress factors. The tank gas is filled with 30% hydrochloric acid, and the upper part of the tank is in a gas phase environment. In the gas phase, macromolecules are small and active, which have penetrated into FRP tanks and gathered at defects, resulting in stress concentration. In addition, in the process of using FRP storage tanks, due to the constant change of storage medium level, the storage tanks are often in an elastic state, and the storage tanks are constantly subjected to alternating stress. The fulcrum at the fulcrum produces upward force on the tank and shear stress at the joint between the head and the tank. The gravity of the head itself, the extrusion of the medium and the strong external collision will make the crack spread rapidly and widely.