Often the failure of subsea bolts has been a major cause of gas or oil leakage in offshore installations, so along with the access difficulties for maintenance teams, preventing the premature failure of these components is certainly desirable wherever possible.
A comprehensive range of corrosion tests have been carried out on our newly developed Everlube 1174® coating, in combination with a variety of pre-treatments.
The results show that Everlube 1174® will provide 1,500h of salt spray protection when applied over a phosphate pre-treatment, 2,500h over Zinc plating and 5,000h over a Cermet basecoat. We tested two bolts and after 1,500h in the salt spray cabinet as per ASTM B117, the bolts showed near zero corrosion and easy removal of the nut.
Everlube 1174® is a low VOC, low-friction, load bearing, thin film, resin-bonded, corrosion-resistant, thermoset PTFE coating.
Everlube 1174® also acts as an excellent insulating shield between dissimilar metals due to its high dielectric strength. This helps to alleviate the problem of galvanic corrosion.
In addition, subsea bolting systems can come into contact with a wide variety of chemicals, from those present in sea water to those used in various oil extraction equipment. Hydraulic fluids for example, are extremely aggressive and can readily breakdown low grade coating systems. Everlube 1174® has been formulated to resist all current hydraulic fluids used in the oil and gas industry.
Typical applications include wellheads, Xmas tress flanges, structural connections and flanges.