摘要 |
A tieback receptacle is configured with an exterior cone and externals seals with a clearance space to accept a tieback shoe that will wash over the receptacle and expand when landed and advanced over the cone. The lower end of the shoe is tapered so that the thickness opposing the upper seal adds to burst and collapse resistance while the tapered lower end allows a thicker receptacle to be used in the area of the lower seal. The expansion can be accomplished with setting down weight which can also enhance the set of the liner hanger below. Minimal expansion in the order of 3% or less is needed. Exterior slots create cement flow passages and a no-go for the stem to prevent damage to the box further below. A metal to metal seal is created at the cone that is straddled by the exterior seals on the extension.
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