Jotun 'Chemflake' now available in two grades

Citation

(1999), "Jotun 'Chemflake' now available in two grades", Anti-Corrosion Methods and Materials, Vol. 46 No. 3. https://doi.org/10.1108/acmm.1999.12846cad.004

Jotun 'Chemflake' now available in two grades

Jotun "Chemflake" now available in two grades

Keywords Abrasive wear, Coatings, Jotun, Steel

Jotun Paints' "Chemflake", a fast-curing glassflake-reinforced vinyl ester coating for the protection of steel in aggressive conditions, is now available in two grades, increasing both the versatility and convenience of this Jotun technology.

According to Jotun, a single coat of "Chemflake Special" can provide exceptional protection against abrasion and many chemicals at elevated temperatures, while "Chemflake Classic" can solve most steel protection problems at standard storage temperatures.

The great benefit claimed of the Jotun "Chemflake" products is that, in most cases, the application of a single coat replaces the traditional time-consuming technique of lining chemical tanks with several layers of glass mat.

After blast cleaning of the steel substrate to Sa 21Ž2 standard, the Jotun "Chemflake" is applied by airless spray, the high solids content of 96 per cent by volume making possible, it is reported, single-coat dry-film thicknesses (DFTs) in excess of 600 microns. The 96 per cent solids content also ensures VOC compliance in virtually all cases.

The time savings resulting from these high DFTs are supplemented by those due to the fast curing of the "Chemflake" products, which are stated to be hard dry in 10-12 hours and fully cured in as little as four days. Compared with traditional epoxy linings, 75 per cent savings in total working time can be obtained, and the fast application and curing give rapid reassurance that optimum coating properties have been achieved.

For protection in extremely aggressive conditions, two coats of Jotun "Chemflake" may be needed, but even in this case, the savings in application time, and hence in cost, can be substantial.

Effective against a very wide spectrum of chemicals, "Chemflake Special" has been approved by Statens Provingsanstalt, the official Swedish testing institute, for the internal protection of tanks containing lead-free petrol. The approval was based on a number of tests including adhesion and impact resistance following immersion in a wide range of aggressive chemicals.

"Chemflake Special" is said to be effective against crude oil at temperatures up to 95°C, naphtha and refined petroleum, slop, waste water, distilled water at up to 60°C, acids, alkalis and a wide range of other chemicals. "Chemflake Special" is believed to be ideal for applications at high temperatures, being temperature resistant, in dry conditions, at up to 150°C without decomposition. It can be applied in DFTs of 600 to 1000 microns.

"Chemflake Classic" is stated to be resistant to a very wide range of aggressive chemicals at their standard storage temperatures. Additionally, the product has been approved, to BS 6290, for drinking water applications. "Chemflake Classic" can be applied in DFTs up to 1,500 microns, the short application times and reduced curing times ensuring fast turnround for the tank to be back in service.

It is reported that following a successful one-year test of "Chemflake" on the interior of a feed solution tank at a Saudi Arabian gold mine, it was decided to use the Jotun product for the complete re-lining of the tank. Before the test, the general condition of the tank was poor; in many places pitting corrosion had reduced the wall thickness by up to 30 per cent on the weld areas. For the test, an area of some 6m² was blast cleaned to a profile of 70-80 microns. "Chemflake" was then applied, with guidance from Jotun's comprehensive step-by-step working manual, at thicknesses varying from 750 to 1,100 microns, and the tank was put back into service within 18 hours.

Inspection of the test area one year later showed "Chemflake" to be still in its "as applied" condition. On the strength of this performance it was decided to protect the whole tank with "Chemflake", which was applied in two 750-micron DFT coats.

Further details from Jotun-Henry Clark Ltd. Tel: +44 (0)171 481 2741; Fax: +44 (0)171 265 1836; E-mail: linda.diamond@jotun.co.uk