Retrievable cementing bushing system

#Hydrocarbon fluids such as oil and natural gas are obtained from a subterranean geologic formation, referred to as reservoir, by drilling a well that penetrates the hydrocarbon-bearing formation. In a variety of downhole applications, casing and/or liners are deployed down along the wellbore and cemented into place. A setting tool string is deployed down through the liners with an appropriate service tool to facilitate the desired service operations, e.g. cementing of the liner or liners within the wellbore. In some applications, the tool string comprises a retrievable cementing bushing which provides a seal against pressure and prevents cement from backing up through an interior of the liner hanger.

#In general, the present disclosure provides a system and method for facilitating a downhole service operation, such as a cementing operation. A retrievable cementing bushing (RCB) is designed to facilitate the service operation and includes a body on which is mounted an engagement lug. The engagement lug is movably mounted for movement in a radial direction and includes an outer engagement feature and an inner engagement feature, e.g. engagement shoulder. The inner engagement feature is oriented for cooperation with a slick joint. The engagement lug is biased in a radially outward direction for engagement with corresponding features of a surrounding wall, e.g. a surrounding packer body wall.

#However, many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.

#Certain embodiments will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements. It should be understood, however, that the accompanying figures illustrate the various implementations described herein and are not meant to limit the scope of various technologies described herein, and:

#FIG. 1 is an illustration of an embodiment of a well system having a tool string with an RCB, according to an embodiment of the disclosure;

#FIG. 2 is a partial cross-sectional view of an example of an RCB, according to an embodiment of the disclosure;

#In the following description, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.

#The disclosure herein generally involves a system and methodology related to performing service operations in a borehole. By way of example, the system and methodology may be used to facilitate cementing operations in wellbores. In this latter example, a tool string is delivered downhole within a surrounding well system, such as a surrounding liner system. The tool string may comprise a variety of components, including a retrievable cementing bushing (RCB). In cementing operations, the RCB provides a seal within the surrounding well system and serves to hold against pressure and to prevent cement slurry from backing up through an interior of the liner hanger. The RCB thus helps force the cement slurry into the annulus surrounding the liner system to facilitate cementing of the liner. However, the RCB can be used with a variety of tool strings and within many types of surrounding well systems depending on the parameters of a given well servicing application.

#According to an embodiment of the disclosure, the RCB is resettable in a manner that allows it to be automatically set at a desired location and then reset if prematurely removed from the desired location. By way of example, the RCB may comprise a bushing body on which is mounted a radially movable engagement lug. The engagement lug comprises engagement features by which it engages corresponding features in the surrounding well system when delivered down through the well system via the tool string. The engagement lug maybe a single lug or a plurality of lugs that are spring biased in the radially outward direction. Radially movable refers to the capacity for outward or inward movement of the engagement lug relative to a longitudinal axis of the RCB. The actual path along which the engagement lug moves may be along a path perpendicular to the axis of the RCB or along a different path, e.g. an arcuate path, resulting in movement in the radial direction.