Casing drilling shoe
AssigneeWeatherford/Lamb, Inc.
InventorMichael Wardley
Life of this patent
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Abstract
A casing drilling shoe adapted for attachment to a casing string and comprising an outer drilling section constructed of a relatively hard material such as steel and an inner section constructed of a readily drillable material such as aluminum. The drilling shoe further includes a device for controllably displacing the outer drilling section to enable the shoe to be drilled through using a standard drill bit and subsequently penetrated by a reduced diameter casing string or liner.
Claims8
A casing drilling shoe adapted for attachment to a casing string, wherein the shoe comprises an outer drilling section constructed of a relatively hard material and an inner section constructed of a readily drillable material, and wherein means is provided for controllably displacing the outer drilling section to enable the shoe to be drilled through using a standard drill bit and subsequently penetrated by a reduced diameter casing string or liner.
A casing drilling shoe adapted for attachment to a casing string, wherein the shoe comprises an outer drilling section constructed of a relatively hard material and an inner section constructed of a readily drillable material, and wherein means is provided for controllably displacing the outer drilling section to a position whereby it does not interfere with subsequent drilling through the shoe for the placement of further casing or a liner down-hole.
Dependencies are inferred from the claim text.