ABSTRACT
Wellbore completions turn a well from a hole in the ground into a producing well. Wellbore completion tools are installed after a well is drilled and enable any completion techniques required to make the well product, such as acidizing or perforating. Completion tools may remain in the well to be used for production. Wellbore completions in unconventional plays isolate different sections in the well for hydraulic fracturing. There are a variety of different techniques used in these applications; each one enables multistage hydraulic fracturing.
Wells are completed using steel pipe, called casing, to install the completion in the well. This casing lines the wellbore so it is commonly referred to as a liner. The assembled casing and completion tools are referred to as the completion string or the liner string. The completion string will contain any completion tools that will be installed in the well that will allow completion and production of the well. When the completion string is placed in the well, the weight of the completion string
needs to be supported, and there are several ways to do so. One option is to hang the weight of the completion string in the intermediate casing. This support can be provided with a liner hanger or a permanent casing packer. Both of these tools use slips to hang and support the weight of the completion in the casing, hence the term liner hanger. Slips are devices used to grip casing and hold the tools at that position in the well. Slips are used in a variety of tools and applications in the industry and are illustrated in Fig. 16.1.
