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Failure of subsea fasteners is the subject of research as the potential repercussions of bolt failure include huge economic losses from the failing equipment, possible collateral damage to surrounding installations nearby on the sea floor, safety concerns for the team who have to remedy the situation, and the potential damage to the environment such as fluid leaks through the ruptured lines. Analysis of prior events in zones such as the Gulf of Mexico has indicated hydrogen embrittlement as a factor in some bolt fractures. Where subsea flanges are secured with multiple bolts, it may be the first bolt fracture is missed as the operation may appear normal. In reality, it is difficult to view and assess the condition of the bolts in such a challenging environment. When failures occurred and the components were returned to the surface and studied, sometimes several of the bolts had succumbed to fractures.

Bolt Corrosion is a threat when fasteners are required in challenging environments like oil fields. Once a bolt has seized, it is difficult and dangerous to replace. The process of hot bolting has been widely criticized as not only being unsafe but by its very nature, it can be expensive and unpredictable in terms of the time required to turn around the bolt and the money spent in removing the corroded bolt and replacing it with a new one. Factoring this across hundreds or thousands of bolts means significant outlay.

Once a fastener has seized due to corrosion, the dangerous practice of hot bolting is often the only way for turnaround crews to swap out the bolts. Doxsteel fasteners have been designed to combat corrosion with a Nickel Cobalt alloy coating evenly electroplated onto each thread. A major advantage of the Doxsteel process is that the entire part is electroplated. When painting or hand-spraying the nuts, coatings can be inadequate, especially in areas like the inside thread of the nut. When components are exposed to harsh environmental conditions, this weakness can lead to corrosion and seizing, with compromised integrity of the fastener. The electroplating process can be controlled such that after testing and cleaning, the Doxsteel nuts and bolts are placed in a bath with NiCo (the Nickel Cobalt alloy), the parts are charged, and electrolysis attracts the alloy, ensuring an even coat on the electroplated fasteners. In addition, the nickel cobalt alloy coating ASTM B994 acts as a barrier to hydrogen embrittlement. With a longer fastener life and 100% traceability, Doxsteel Fasteners offer a warranty which guarantees no seizing within 5 years. The average probable fastener life is 21 years. Over time, the return on investment is realized in the lifespan of the fasteners and the predictability in turnaround without the need for hot bolting, which can be expensive and unpredictable in terms of money and time.

The journey to develop coated fasteners which can stand up to the harshest environments started in the late 1990's when a contract for fastener turnaround and anti-corrosion paint application in Mexico became a complicated project. Data from Mexico City was not representative of all areas within the scope of the project. In areas such as the Gulf Coast and the rainforest jungle, corrosion rates were much higher and many of the bolts had seized. The bolts were unable to turn as they had badly corroded. The only way to remove them was to cut and then torch them. This not only had cost implications but also greatly increased the time required to complete the job.

Understanding the life expectancy of a steel fastener drives maintenance schedules and budgets. Being able to turnaround fasteners quickly and without hot bolting saves time, money and potentially lives. Doxsteel fasteners are designed to last, with a life expectancy of 21 years. Unlike others in the industry, Doxsteel backs up their product with a 5-year no seize warranty.

Seized fasteners provided the impetus to find a smarter solution to source industrial steel bolts. Doxsteel Fasteners are made from carbon steel and are coated with a Nickel-Cobalt alloy. This coating offers improved resistance against corrosion, extending the life expectancy of the bolt. With bolts which do not seize, maintenance is easier to manage and is more predictable. Furthermore, the elimination of hot bolting reduces costs, saves time and promotes safety.