Patent ID: 11946332
Assignee: HALLIBURTON ENERGY SERVICES, INC.
Field: Materials, metallurgy (Chemistry)
Classification: CPC E  C | IPC C  E

Claim 0:
1. A swellable packer assembly for positioning in a wellbore, the swellable packer assembly comprising:
a mandrel;
a sealing element disposed about a least a portion of the mandrel, the sealing element formed of a material responsive to exposure to a fluid in a wellbore to radially expand from the mandrel; and
a degradable metal coating disposed about at least a portion of an outer surface of the sealing element, the degradable metal coating fluidly isolating the portion of an outer surface of the sealing element from a fluid external to an exterior surface of the coating, wherein the degradable metal coating comprises a doped magnesium alloy selected from the group consisting of:
a doped WE magnesium alloy comprising 86.6% to 90.6% magnesium, about 4% rare earth metal yttrium, about 4% rare earth metal that is not yttrium, 1% to about 5% dopant from the group consisting of iron, nickel, copper, and any combination thereof, and selected about 0.4% supplemental material of zirconium, each by weight of the doped WE magnesium alloy;
a doped AZ magnesium alloy comprising about 88.5% magnesium, about 9% aluminum, about 0.7% zinc, 1% to about 5% dopant selected from the group consisting of iron, nickel, copper, and any combination thereof, about 0.2% supplemental material of manganese, and about 0.3% supplemental material of zinc, each by weight of the doped AZ magnesium alloy;
a doped AZ magnesium alloy comprises about 94.5% magnesium, about 3% aluminum, about 1% zinc, 1% to about 5% dopant selected from the group consisting of iron, nickel, copper and any combination thereof, and about 0.3% supplemental material of manganese, each by weight of the doped AZ magnesium alloy;
a doped ZK magnesium alloy comprising about 91.7% magnesium, about 5.9% zinc, about 0.2% zirconium, and about 2% dopant selected from the group consisting of copper, nickel, iron, and any combination thereof, each by weight of the doped ZK magnesium alloy;
a doped ZK magnesium alloy comprising about 89.9% magnesium, about 3.2% zinc, about 0.6% zirconium, and about 6.3% dopant selected from the group consisting of copper, nickel, iron, and any combination thereof, each by weight of the doped ZK magnesium alloy; and
a doped AM magnesium alloy comprising about 91.4% magnesium, about 6% aluminum, about 0.2% manganese, about 2% dopant selected from the group consisting of copper, nickel, iron, and any combination thereof, about 0.2% supplemental material of silicon, and about 0.2% supplemental material of zinc, each by weight of the doped AM magnesium alloy;
wherein the degradable metal coating is selectively removable from the mandrel downhole so as to expose the sealing element to the fluid in the wellbore.