THE PROBLEM
The pallet inverter had corroded on the wearing surface. This was causing damage and contamination to the clients sheet materials that was causing reputational damage.
SOLUTION
We proposed the application of a durable protective coating in the form of Corroless ACO.
As part of our standard quality assurance it was identified by a soluble salt test that these were present in very high levels – something that many others would overlook. This validated the essential nature of this quality assurance check as part of our standard application process as perhaps it would not have been expected to find such high levels.
Initially the area to be treated was cleaned by method of high pressure washing – this had to be repeated three times in order to reduce the soluble salts present to the point determined by the protective coating manufacturer.
The surface to be treated although corroded was extremely smooth and required abrasive blasting in order raise sufficient profile in order for the protective coating to adhere sufficiently well in order to withstand the rigors of the duty expected.
Given the pallet inverters location within the factory it was not possible to prepare the surface by conventional abrasive blasting. Instead we elected to prepare the surface by method of low dust sponge blasting. To further control the production of atmospheric dust the pallet inverter was sheeted in. These two measures proved highly effective with minimal dust creation.
The steel was prepare to SA2.5 as per ISO8501-1 with a minimum surface profile of 75 microns achieved. This was tested and recorded using a surface profile needle gauge.
All surfaces were vacuumed clean and this again was verified with a dust tape test. Climatic conditions were also tested and recorded to ensure compliance with the manufacturers recommendations.
Corroless ACO was then applied in two coats of contrasting colour at a target thickness of 500 microns per coat. This was checked during application using wet film thickness gauges to ensure the protective coating was applied in line with the protective coating manufacturers recommendations.
Dry film thickness readings were taken after each coat and where necessary touch ins made using the same material to achieve the required thickness.
Although hardly the largest protective coating contract we have undertaken it proved the importance of undertaking a thorough quality assurance regime as when undertaking protective coating applications you can frequently be surprised.
