Wear resistant coating for keel joint
AssigneeVetco Gray Inc.
InventorsFife B. Ellis, Kim H. Phan, Eric J. Schultz
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Abstract
A method of reducing stress and wear on one or more components in a keel joint assembly in which a cobalt-based, wear resistant alloy coating is applied to the surfaces of one or more components. The use of the coating reduces stress and wear and achieves improved corrosion, galling, erosion and abrasion resistance as compared to other currently known and applied methods. In the present invention, the coating would preferably would be applied to the surfaces of the mating components of the keel joint.
Claims16
A method of reducing wear on one or more subsea components that slidingly engage each other, the method comprising:
- applying a coating to one or more surfaces of the components, the coating comprising a cobalt-chromium-nickel alloy, whereby the coating reduces stress and wear on the components caused by relative sliding movement of the components, wherein the coating by weight percent consists essentially of 23.5–29.0% chromium, 7.0–12.0% nickel, 3.0–6.0% molybdenum, 1.0–5.0% iron, 1.0–5.0% tungsten, 0.1–1.5% manganese, 0.05–1.00% silicon, 0.02–0.20% carbon and an amount of cobalt.
A method of reducing wear on an offshore riser assembly having a submerged partially spherical convex bearing element that flexes in sliding engagement with a partially spherical concave bearing element, the method comprising:
- applying by a welding process a coating to each of the bearing elements, the coating consisting essentially of cobalt, chromium, nickel, molybdenum, iron and tungsten, wherein the coating by weight percent consists essentially of 23.5–29.0% chromium, 7.0–12.0% nickel, 3.0–6.0% molybdenum, 1.0–5.0% iron, 1.0–5.0% tungsten and an amount of cobalt.
In a subsea well production assembly having first and second submerged metal components with bearing surfaces that slidingly engage each other, the improvement comprising:
- a cobalt-chromium-nickel alloy coating on the bearing surface of at least one of the components wherein the coating by weight percent consists essentially of 23.5–29.0% chromium, 7.0–12.0% nickel, 3.0–6.0% molybdenum, 1.0–5.0% iron, 1.0–5.0% tungsten, 0.1–1.5% manganese, 0.05–1.00% silicon, 0.02–0.20% carbon and an amount of cobalt.
Dependencies are inferred from the claim text.