Six Points when evaluating the Best Tank for your Next Project:

Where should I start?

When buying a water storage tank, working out the configuration and selection process often is something that needs to be done in the early stages of project design. Applying for and securing funding, timing of construction, and overall project costs all play a factor. As many areas have a single source of water storage, the tank design plays a crucial role in meeting the current and future needs of a community.

There are three types of liquid storage tanks available that are considered for municipal water storage applications: glass-coated bolted steel, welded painted steel and concrete.

1. Design & Configuration

Reservoirs have a greater diameter than height and can be used with a pumping system or can be gravity fed. Depending on the diameter, snow loads and other factors, the roof of glass-bolted tanks can vary. They can be a free-span aluminium geodesic dome, consisting of panels mounted on a rigid structural frame, or the same glass-fused-to-steel material.

The tank floors usually are constructed with reinforced concrete or they can be glass-coated panels depending on site and design conditions.

2. Manufacturing Process

The technology and manufacturing process of this equipment sets these tanks apart from painted steel or concrete structures. When using the factory manufacturing process, the uncontrolled variables are eliminated – unlike field manufactured products such as painted steel or concrete tanks. Worker experience and extreme climatic environmental conditions that are proven to have a significant effect on in-field manufactured products have minimal effect on the glassing process. In addition, the tanks can be erected year-round as the manufacturing is completed in the factory and only the assembly of the components is required in the field.

3. Coating

All storage tanks have a coating. The coatings available today consist of either paint, concrete or glass. The water resistance and air tightness of glass offer advantages.

The glass coating process begins with a glass frit that is mixed with other minerals and water to create a liquid slurry. This glass slurry is then robotically sprayed in precise amounts and thicknesses on to previously cut and rolled, punched, grit-blasted and cleaned steel sheet panels. The panels through a furnace at around 815DegreeC. This heat melts the silica glass slip into the surface of the grit-blasted steel. This completes the mechanical bond, as well as the chemical bond between the steel and the silica glass.

Different coatings for other tanks rely on a mechanical bond of the coating to the underlying material. The chemical bond strength is many times the holding strength of the conventional mechanical bond and prevents any undercutting of the coating, which can allow spreading of corrosion on the primary steel material. This benefit can best be explained by imagining a scratch on an automobile. Because that coating only has a mechanical bond, if the steel is exposed, corrosion will occur. Left untreated this corrosion will expand and creep beneath the surrounding painted surface and compromise the remaining coating.

This often is witnessed with raised bubbles, spreading rust and weakened substrate. The chemical bond of the glass-fused-to-steel coating prevents this spreading of corrosion in the event of the coating being compromised.

4. Tank Construction

A jacking system is used when erecting a glass-coated bolted steel storage tank. Tanks are assembled from the top down allowing for a safer and faster construction environment. The erection process is normally completed within a week or two, which saves costs to the owner if you’re paying for staff to be on site.

5. Maintenance/Life Time Value

Glass-coated, bolted steel tanks have a long lifetime. Glass-coating never needs painting because its appearance is permanent, meaning they are a great option in areas where a pleasing visual appearance is sought. Repainting budget or repair budget for aged concrete can be saved and prioritised elsewhere.

6. Project Flexibility

The bolted design and erection of this product gives flexibility. Because manufacturing is completed in a factory, there’s no need for a large staging area. The construction of the tank typically can be completed with a cleared area of roughly 2m-3m around the tank diameter. This small footprint can save thousands on the overall project beyond the price of the tank itself. The panels themselves can be hand-carried and easily assembled without cranes or special equipment, allowing this tank to be installed in many locations that would be impossible for other tank types.

Conclusion

Initial construction costs, anticipated life and long-term maintenance costs are significant factors relative to the various tank designs and materials available today. The long-term maintenance costs and life cycle must be considered when selecting the appropriate tank product for a specific project.

Contact Reliant Solutions for help with planning your next storage tank project. www.reliant-solutions.co.nz/contact-us