Sidepocket mandrel apparatus and methods

Abstract

A sidepocket mandrel apparatus including a mandrel body formed of a resin-based material, such as, for example, fiberglass. The mandrel body defines a through-bore and an enlargement axially offset from the through-bore. A valve receiving pocket formed of a rigid material is secured within the offset enlargement of the mandrel body so as to be substantially parallel to but axially offset from said through-bore. Such pocket may, for example, be formed of stainless steel or of a composite plastic material. The sidepocket mandrel is formed by machining a valve receiving pocket from a rigid material. The valve receiving pocket is removably secured on a substantially cylindrical molding rod, together with at least one removable mold piece, the molding rod and removable mold pieces defining a desired inner shape of the sidepocket mandrel. Fiberglass is then wound around the valve receiving pocket, molding rod, and removable mold pieces to form a fiberglass mandrel body. The molding rod and mold pieces are removed from the fiberglass mandrel body, the fiberglass is cured, and the fiberglass is thereafter machined to form threads adjacent each end of the mandrel body.

Dependencies are inferred from the claim text.