Fire Protection Coating – Structural Steels
THE RESULT
The successful application of a specialist intumescent fire protection coating system, to C4 Environmental Standard, to 22 structural steel columns at an energy-from-waste power plant in Lincoln; providing protection from potential fire damage for a minimum of 60-minutes.
Powertherm people provided technical grit blasting services to remove the existing protective coating which required maintenance due to its age. Our scaffold access team also played a vital role in the success of this project through the provision of scaffolding towers to provide safe access to the workface – with some columns standing 36m high – and encapsulation of the towers to prevent contamination of the surrounding environment from blasting and coating procedures.
THE CHALLENGE
Our client required repairs to the fire protection coating that was applied to 22 structural columns due to the deterioration of the existing coating and subsequent mandatory maintenance requirements where a minimum level of protection is not being provided by the coating system.
In addition, the coatings system also had to provide corrosion weather protection as the columns were situated outside and last a minimum of 10 years before first maintenance requirements. Before the new coating system could be applied, the existing system needed to be removed from the columns. And appropriate access was also required by the client to provide safe and cost-effective access to the workface.
Being multidisciplined, we could provide the client with a proposal that delivered all the services they required with the bonus of only needing to deal with a single supplier. As with all coating applications, a certified inspector was required to inspect and approve the coatings system – Powertherm have the competent people in-house who are NACE certified inspectors.
PROJECT/ SITE DETAILS
Industry: Power Generation
Contract Type: Maintenance
Services:
- Industrial Coatings (intumescent fire protection coating)
- Scaffolding Access
- Surface Preparation (grit blasting)
Location: Lincoln, UK
Type: Energy-from-waste (EFW)
Fuel: Residual waste
Power Output: 13.1MW
Processing capacity: 190,000 tonnes of waste into energy per year
MATERIAL SPECIFICATION
- Primer coat (x2) of Intercure 200 @ 75 microns DFT.
- Intumescent Interchar 1260 @ 400um DFT.
- Interthane 990 @ 50um DFT.
WHAT WE DID
The first phase of the project required our access team onsite to erect scaffolding towers around the 22 external building columns to provide safe access to the workface. Ranging from 7 – 36m in height, scaffold gangs erected scaffold towers, using the Layher system, in 2m lifts, with applicable guardrails and toe boards.
The towers were also sheeted to the top as the columns were to be blasted and painted, and to comply with the clients’ requirements to not contaminate the onsite drainage/ water systems. sheeted scaffolding provides encapsulation which protects both the workface from adverse weather (if the project is based outdoors) and the surrounding environment from any potential contamination.
Next our expert blasters were onsite to blast clean the columns of the existing, deteriorated, insufficient fire protection coatings system. Grit blasting was executed to Sa 2.5 standard. Blasting removes existing coatings, any surface contaminants, and provides a suitable profile of the substrate – the structural columns – for better adhesion of the new coatings system.
Once all the existing paintwork and intumescent coating had been removed and the surface of the columns suitably prepared, our industrial painting operatives applied the first coat of primer. Intercure 200 at 75 microns DFT was specified; this primer provides corrosion protection and acts as a base for the intumescent coating. Teams then repeated this process, applying a second coat of Intercure primer to the same spec to ensure full coverage of the structural columns and provide maximum protection.
Following the appropriate curing time of the primer, Powertherm operatives were then ready to apply the fire protection coating. This layer of the coating system was specified as Interchar 1260, applied at 400 microns DFT. In the event of a fire, this intumescent coating is designed to expand, and create an insulating layer (char) that provides protection to the underlying structure, in this case the structural steel columns, for a given period of time – a minimum of 60-minutes for this project.
Passive fire protection coatings work by expanding to form an insulating layer when subject to an extended period of high temperatures. This creates a protective barrier that limits heat transfer between the substrate and the source of heat: unprotected steelwork for example can take just a few minutes to reach extremely dangerous temperatures upwards of 550°c when subject to a fire. This can ultimately have catastrophic consequences.
To achieve the desired finish and colour of the client, a top and final coat of the coating system of Interthane 990 was applied at 50 microns DFT. This coat provides additional protection but also a visually appealing finish to the columns.
All 4 coats of protective paints/ intumescent coating were expertly applied by airless spray gun, with a total coverage of 535 m² across the 22 columns.
Finally, and to comply with regulations our in-house NACE certified painting inspector was onsite to inspected and approve the coating system was applied correctly to comply with appropriate standards, ensuring it lasts it’s expected life cycle before first maintenance. All coatings were subsequently certified as fit-for-purpose, passing the inspections.
Powertherm’s Passive Fire Protection (PFP) Solutions
We offer a wide range of PFP services including intumescent coatings and cementitious products. Our highly skilled and qualified applicators are approved to install the latest technical PFP solutions to steelwork, skirts, process, and storage assets to name a few. From single project applications to term maintenance contracts on refineries, we offer turnkey solutions to major blue-chip clients, to protect their teams and assets.