Free Webinar: Flange Isolation and Remote Monitoring

Sign Up!

What is a plural component protective coating and what is it used for?

By Wade Hannon | Published: May 31, 2018 | Last updated: June 13, 2018
Presented by Graco Inc.

Plural component protective coatings, as the name suggests, are coatings that are made up of separate elements that are combined prior to application. High solid materials such as polyurethane, polyurea, and epoxy are some of the common materials that are combined in plural component coatings.

The components of the coating product are first heated separately by the spraying equipment to reduce their viscosity. Once the required temperature and viscosity are reached, the components are sent to the spray gun where they are mixed to preset optimal ratios. Because the high solid elements dry quickly, they are only mixed moments before being sprayed from the gun nozzle onto the substrate.

Plural component coatings are used to protect metal substrates on structures such as pipes, bridges, storage tanks and marine vessels. They are commonly used for:

  • Joint and crack fillings
  • Roof coatings
  • Roof and wall insulation
  • Passive fire protection
  • Corrosion protection in harsh environments

Some of the advantages of plural component protective coatings include:

  • Better environmental compliance – The high solid elements that make up plural component systems contain very little solvent content, and in the case of 100% solid coatings, no solvents. Therefore, little to no volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) are emitted into the atmosphere, and post-application cleanup is kept to a minimum. (For more on VOCs and HAPs, read The Dangers of Typical Corrosion Prevention Solutions.) For this reason, plural component systems are ideal for satisfying compliance with environmental standards.
  • Durability and service life – Although plural component systems usually incur a higher upfront cost, these coatings have the potential to reduce lifetime costs by extending the service life of the protected component. These coatings are known to have a service life of 15 to 20 years, which can significantly reduce maintenance costs.
  • Faster turnaround times – Plural component systems possess significantly faster curing times than solvent-based coatings. Surfaces coated with high solid coatings can be walked on in a matter of hours after application. In addition, high solid coatings can achieve the desired film thickness in fewer coats, which also means reduced completion time.
  • Flexibility – Automatic mixing of the high solid bases can be adjusted for various applications, allowing the mixing chemistry to be customized for tighter, stronger coatings and more efficient use of material.

Presented By

Logo for Graco Inc.

Share this

  • Facebook
  • LinkedIn
  • Twitter

Written by Wade Hannon | Area Sales Manager, Specialty Products at GRACO Inc.

Wade Hannon
Wade Hannon is an Area Sales Manager – Specialty Products at GRACO Inc. with responsibilities for equipment demonstrations, technical support, distributor development and sales support, marketing and promotion within assigned territories, trade shows and internal sales support.

More Q&As from our experts

Term of the Day


Tribology refers to both the science and technology involving lubrication, friction and wear. It comes from the Greek term…
Read Full Term

Don't miss the latest corrosion content from Corrosionpedia!

Subscribe to our newsletter to get expert advice and top insights on corrosion science, mitigation and prevention. We create world-leading educational content about corrosion and how to preserve the integrity of the world’s infrastructure and assets.

Go back to top