Got it covered - Surface treatment & coatings

When it comes to surface treatments and coatings it all about protection, whether it’s from corrosion, the elements or other factors. These coatings and treatments can be done as part of the manufacturing process or onsite as we see from these examples from Dörken and Owlett-Jaton.

Owlett-Jaton - First Class Secondary Processing Service

Owlett-Jaton is renowned for offering a ‘one-stop-shop’ service for secondary processing, including surface treatments, coatings, thread-patching, and machining to bespoke drawings.

One of Owlett-Jaton’s largest customers - a global distributor that provides inventory management to some of the largest companies in the world, recently won a new contract to supply standard and non-standard fasteners. The contract was to supply a new automotive/yellow goods venture. They immediately turned to Owlett-Jaton for support for several reasons.

The new contract included hexagon and flange bolting in various grades of steel with several types of plating requirements, including zinc flake (for example, Geomet or Delta Protekt) and Zinc Trivalent Heavy Passivation, along with a range of specially manufactured fasteners.

Zinc flake finishing was introduced into automotive and yellow goods manufacturing to eliminate Hydrogen embrittlement issues when plating higher-grade steel fasteners. This treatment offers greater resistance to corrosion than standard bright zinc plating, necessary due to the harsh working environments the products would be subjected to.

The extensive range of stocked products from Owlett-Jaton fulfilled the majority of items; their dedicated Specials team were responsible for sourcing the balance of non-stocked fasteners.

Owlett-Jaton’s Subcon team was responsible for decanting the product from the manufacturer’s packaging into stillages, before transporting the product to their relevant secondary process partners. Once the refinishing of the product was carried out, the product was re-packaged in-house, complete with data on the label containing product code and description, quantity, barcode, and batch reference. The stock is held at Owlett-Jaton’s warehouse facility and delivered as and when required by the customer on a call-off basis.

Special fasteners often end up in demanding applications, resulting in them potentially requiring additional certification, and this contract was no exception. The customer required Production Part Approval Process (PPAP) and Initial Sample Inspection Reports (ISIR) documentation; Owlett-Jaton were able to supply them accordingly.

Owlett-Jaton’s Specials team also provided Country of Origin and full batch traceability to the special products. This is supported by their ISO 9001:2015 quality systems and ISO 14001:2015 environmental management system.

This level of service all adds up to convenience, efficiency, and peace of mind for the customer, ensuring that their requirements are supplied right the first time.

Enquiries should be directed to Owlett-Jaton’s sales offices or the Field Sales Team. Contact details can be found at

Dörken - Zinc flake without oven - a powerful alternative

Zinc flake coatings impress with cathodic corrosion protection, in which base zinc sacrifices itself for the underlying material. A low coating thickness, high fitting accuracy as well as an attractive appearance are further advantages of this coating. After pre-treatment of the surface, a component is coated. The application technique varies depending on the size and geometry of the component. Possible methods include spraying, dip-spinning, rack-dip-spinning and dip-drawing. The material application is followed by pre-drying and curing in the oven, during which the coating hardens and becomes a uniform, hard layer.

The solution for special cases

However, it is not always possible to cure a coating in an oven. This can be for a variety of reasons. On the one hand, the component may be too large or too immobile. On the other hand, there are components which or whose parts must not be exposed to high temperatures. For these cases, Dörken has the ideal solution: The room-temperature curing zinc flake dries within approximately 60 minutes at an ambient temperature of 20 to 25 degrees Celsius. Forced drying is also possible. Even without a curing process, this solution offers a high level of corrosion protection and, apart from zinc, does not contain any heavy metals such as chromium (IV). With the help of Delta-Protekt® Repair, the room-temperature-curing zinc flake coating in the practical spray can, individual defects can also be repaired, or small areas coated.

Corrosion protection far above the rooftops of Cologne

The room-temperature-curing zinc flake has already been able to show what it can do in a very special place. In 2018, the product was used on the Petersglocke in the Cologne Cathedral, which is full of history. As the clapper of the bell swung irregularly, a new mount was developed, designed and produced. In order to safely protect this load-bearing element from corrosion, the experts at Dörken were contacted. The corrosion protection system from the Herdecke-based company is more than able to withstand external influences such as mechanical stress as well as strong temperature fluctuations. Thanks to the room-temperature curing solution, the 800-kilogram component could be coated on site in the bell tower. Now the Petersglocke rings again safely above the roofs of Cologne.