Manufacturing Process for Steel Tanks and Fiberglass Storage Tanks

Steel Storage Tank Manufacturing:

Our equipment is often fabricated from A36 carbon steel, stainless steel, alloy metals and aluminum based on your requirements for size, internal and external pressure requirements, stresses encountered during operation and more. Worthington is licensed to manufacture products designed and built in compliance with multiple international standards, including those of the American Society of Mechanical Engineers (ASME), the American Petroleum Institute (API), and the American National Standard Institute (ANSI), among others.


Fiberglass Storage Tank Manufacturing:

There are three different fabrication techniques that we utilize for our fiberglass tanks: hand layup, chop spray and filament winding. 

Hand layup is a manual process of laying fiberglass material in a mold and applying resin by pouring, brushing or spraying. The resin is then forced into the fiberglass using specially designed rollers. Advantages to this process include low cost of startup equipment and flexibility for a wide range of part sizes. Disadvantages are that the process is extremely dependent upon the ability and expertise of the fabricator, and since it is such a manual process, fabrication of large pieces is very slow.

Chop spray is where continuous strands of fiberglass are fed into a “chip gun” which chops the fiberglass into smaller strands. These strands along with resin are then sprayed onto a mold; a roller is used to force the resin into the fiberglass. This type of fabrication is typically low in initial investment and allows for a wider ranger of part sizes.

Filament winding involves wrapping multiple continuous strands of fiberglass onto a rotation mandrel. Resin is applied either by spraying or pulling the strands through a resin bath. Filament winding can be combined with the chop spray method. By combining the two processes, a monolithic tank wall with superior strength and liquid retention capabilities can be produced. Strength of laminate is derived from the amount of fiberglass contained in the resin, filament winding gives the greatest fiberglass to resin ratio, which provides the highest weight to strength ratio.

The last step in the manufacturing process is the final coat of resin or gel sprayed over the exterior. This final coating gives the tank a maintenance free exterior surface. 

Our team can provide the full spectrum of service offerings—design/build, build-to-spec, and production run quantity fabrication. These services encompass in-house engineering (link to engineering capabilities), drafting, machining, testing, NDE, and transportation as well.