Hempel has launched a new high quality topcoat ideally suited for steel structures exposed to severely corrosive atmospheric environments, Hempaxane 55000.

The new product is based on both epoxy and polysiloxane binder chemistry, combining the anticorrosive properties of epoxies with very long colour and gloss retention from the polysiloxane binder.

With its adherence to solvent emission restrictions, it is said to outperform products of polyurethane topcoats.

Hempel claims that Hempaxane 55000 has undergone thorough testing at every stage of development, involving both in-house testing and field trials on a wide variety of different structures.

Hempaxane 55000 has passed pre-qualification for NORSOK M501 - rev.4 standard using only a zinc-rich primer as a preceeding coat. It has also passed mechanical strength tests, abrasion resistance tests and colour and gloss retention tests, all according to recognised standards.

Typical uses of

Hempaxane 55000 include the protection of steel structures from the harmful effects of weather, environment and operating conditions, whether this is offshore, onshore or inland.

The coating can be used on offshore installations, petrochemical plants, tank farms, wind turbines and bridges - any structure that requires long durability and is difficult or expensive to maintain.

Hempaxane 55000's ability to form a hard coating within just a few hours, makes it ideal for use in online production facilities or other situations where fast drying means faster throughput and increased production flow.

According to its maker, Hempaxane 55000 provides much better corrosion protection than conventional topcoats such as polyurethanes.

This is possible because Hempaxane 55000 forms an exceptionally effective barrier to the passage of water and because it forms a very hard, impact and abrasion resistant coating to protect against mechanical damages.

Furthermore, Hempaxane 55000 provides resistance to UV light from the sun, meaning that the coating maintains its gloss and colour for much longer than other topcoats, such as acrylics, alkyds and polyurethanes, says Hempel.

Due to the combination of colour and gloss stability with corrosion protection properties, Hempaxane 55000 can substitute both an epoxy coat and polyurethane coat, and thereby in certain cases reduce the number of coats in a coating system.

Last year, Hempel released Hempadur Mastic 45881, a two-component, high solids epoxy coating with good adhesion and wetting properties, touted as being particularly suitable for the harsh conditions of the Gulf.

The advantages cited for the product include:

_ A high-solids content and high-build nature, which makes the system very cost-effective and volatile organic compliant (VOC).

_ Excellent surface tolerance, which makes it ideal for areas where only minimal surface preparation is possible; being self-priming, it can be used as an intermediate as well as finishing coat in a multi-coat system;

_ Good mechanical properties, making it durable and long-lasting;

_ Fast-drying, helping contractors save time and money;

_ It requires a minimum number of coats to attain the required thickness, thus bringing about savings in application costs; and

_ It can be applied by airless spray.

Cherian Varghese, Hempel's national co-ordinator for protective coatings has said that the product "is specially designed for the protection of structural steelwork in a corrosive environment and has been successfully used on exteriors of large tanks, chemical and petrochemical plants, bridges, windmills, in above-the-waterline marine locations such as ship decks and superstructures and even on grain cargo holds."

Available in a range of colours, Hempadur Mastic 45881 is approved by a major oil company in Saudi Arabia for external protection of large tanks and steel structures.

Hempadur Mastic 45881 has been tested under different exposures and carries various certificates and approvals.