Shielding tanks and pipes from the elements with protective coatings

In the last few years, the many benefits of polyurethane and polyurea systems have made them appealing as options to traditional epoxy and acrylic systems. UV-resistant aliphatic formulas supply long-lasting exterior or aboveground security, while fragrant solutions offer superior corrosion protection for belowground setups for both interior and exterior surfaces. Both offer a fast return to service for OEMs wanting to increase performance and performance.

It is also essential for both interior and exterior applications that the coatings are chosen to be versatile adequate to withstand growth and contraction. Steel water tanks often include joints and seams created for motion in action to changes in the environment. The coatings utilized to secure these surface areas should have adequate flexibility to match the level of movement that is expected.

Also, coatings used to protect steel in these difficult conditions must fulfill increasingly stringent environmental policies, especially concerning the unstable natural substance (VOC) content. The majority of technologies in use today are either water-based or 100% solids systems. Quick setting systems (polyureas and polyurethanes) used in OEM centers are 100% solids, absolutely no VOC, plasticizer, and extender-free.

Standard Systems

Most epoxy systems presently used in the market are between 55% and 70% solids and consist of combustible solvents. The higher majority of quick setting polyurethane and polyureas are 100% solids and include zero flammable solvents.

Normally two or three layers of epoxy are applied, among which might be a zinc-rich epoxy primer. In the last few years, polyurethane elastomers have been increasingly used to secure the interiors of safe and clean water tanks and pipe externals due to their quick cure, greater flexibility, and capability to function as a barrier against moisture, chemical attack, and ice damage.

Epoxies have likewise often been used as guide layers on the exteriors of water tanks and pipes due to their excellent adhesion and resistance to water and chemicals. Waterborne acrylic coatings have been commonly utilized as the overcoat in protection systems for water tank exteriors due to their ease of use and lower expense. They tend to be fairly long-lasting, versatile, and resistant to moisture, chemicals, and UV deterioration, although limited by their movie construct.

High solids polyurethanes and polyureas are higher-performance, longer-lasting coatings (> 30-year service life) that can be formulated with a large range of versatilities.

Polysiloxanes and fluorinated polyurethanes have also been established as topcoats for the exteriors of safe and clean water storage tanks. These advanced coatings also have a long life span (~ 30 years), which implies longer periods between coating removal and replacement. However, they may not be zero-VOC and are more costly. Therefore the general cost-benefit need to be thought about.

Why utilize 100% solids coatings?

The majority of fast-set polyurethane and polyurea elastomers are 100% solids coatings that treat very rapidly and adhere strongly to steel. Other substrates can be coated. However, they may require a primer. Because of these ultra-high solids systems' special chemistry, they can be formulated to the desired level of flexibility required to withstand the movement related to steel tanks and pipes.

With the right option of starting products, it is likewise possible to develop both polyurethane and polyurea systems with curing times that enable the application of perfectly smooth, high-build coatings. Importantly, 100% solids polyurethanes and polyureas utilized for OEM safe and clean water tank coatings and linings treat a lot more rapidly than epoxies - normally within minutes to hours, instead of days will cure below 50 degrees F.

Aromatic Or Aliphatic

Both fragrant and aliphatic systems for potable water pipe and tank applications cure quickly and supply exceptional, long-lasting corrosion protection. Both can be utilized for outside and interior applications; nevertheless, aliphatic systems normally find a use for the coating of the outside surface areas of water tanks and aboveground pipes. In contrast, aromatic systems are preferred for interior protection and underground applications. What is the distinction?

Aromatics have chemical bonds in them that take in UV radiation, which results in unfavorable yellowing of these coatings in time. Aliphatics do not possess this bond and therefore are not affected by UV radiation. Their color, gloss, and other look attributes are kept for prolonged periods, even when exposed to sunlight.

Aliphatic polyurea and polyurethane coatings are more expensive, nevertheless. One solution to this problem is to use a thick aromatic basecoat with a thinner aliphatic overcoat to minimize the overall cost.

Also, polyaspartic coatings go on thinner than regular aliphatic polyureas but thicker than conventional solvent-borne aliphatic polyurethanes, making them ideal for high-performance overcoats. Like routine polyureas, their quick cure time makes them ideal for OEM drinkable water tank and pipe production, where a quick turnaround time corresponds to greater performance and greater profits.

For the interiors of the safe and clean water tank and the exterior and interior of belowground piping, UV exposure isn't an issue; there is no requirement for aliphatic chemistry in these applications. Aromatic systems supply long-term protection integrated with quick go back to service.