Design of Fiberglass Storage Tank Structure

Design of Fiberglass Storage Tank StructureThe inner lining layer directly contacts the storage medium, and its main function is to prevent leakage, resist corrosion, and ensure smooth inner walls. The structural layer bears all the loads of the storage tank (internal pressure, external pressure, self weight, wind load, etc.).

Structural design of bottom and top of fiberglass storage tanks

Tank bottom: divided into flat bottom (suitable for atmospheric pressure and ground installation) and conical bottom (suitable for working conditions where the medium needs to be drained completely); A cushion layer (such as epoxy mortar, rubber sheet) should be provided at the contact area between the tank bottom and the foundation, and the edge of the tank bottom should be wrapped to prevent edge delamination.

Tank top: commonly used elliptical head (pressure storage tank) or disc-shaped head/flat top (atmospheric storage tank); Flat top storage tanks need to be equipped with internal support or external reinforcement to avoid top collapse; Manholes, connecting pipes and other accessories should avoid the stress concentration area of the head.

Design of Fiberglass Storage Tank StructureStructural reinforcement of interfaces and attachments:

During the design of accessories such as flanges, manholes, inlet and outlet ports, and level gauge interfaces for fiberglass storage tanks, it is necessary to:

Adopting local thickening reinforcement: a reinforcement layer of 5-10 times the diameter of the interface is made around the interface, and the laying method is "inner layer short cut felt+outer layer wrapped yarn".

Ensure the connection strength between the interface and the tank body: The metal flange needs to be coated with FRP for corrosion prevention, and the connection surface with the tank body needs to be designed for anti slip (such as setting anchor bars).

Adaptive design of structural forming process for fiberglass storage tanks

Hand lay up process: suitable for small and irregular storage tanks, the structural layers need to be compacted layer by layer to avoid interlayer gaps.

Winding process: Suitable for large and medium-sized vertical/horizontal storage tanks, the winding angle and tension are controlled by computer to ensure the uniformity and strength consistency of the structural layer.

Spray technology: suitable for the construction of the inner lining layer of large storage tanks, requiring control of spray pressure and fiber content.

Structural adaptation of fiberglass storage tanks under different working conditions:

Chemical medium storage: For strong corrosive working conditions, a thick inner lining layer (≥ 1.5mm) is required, and heat-resistant resin (operating temperature ≤ 120 ℃) is used; A wear-resistant layer (such as adding silicon carbide particles) should be added to the inner lining of the medium containing solid particles.

Application in the field of environmental protection: When storing acid-base wastewater and desulfurization slurry, negative pressure conditions (such as siphon negative pressure during emptying) should be considered, and reinforcement rings should be added; The storage tanks for odor treatment (such as absorption liquid storage tanks) need to be strengthened in sealing, with double sealing of sealing rubber rings and flanges at the interface.

Pressure/Vacuum Storage Tanks: Pressure storage tanks require an increase in the thickness of the structural layer, an elliptical head, and a hydrostatic test (with a test pressure of 1.25 times the design pressure); The external pressure stability of the vacuum storage tank needs to be calculated, and the ring spacing should be strengthened to ≤ 1m.