Cementing Stinger Operations Procedure & Equipment
Inner string or stinger cementing is a technique typically used with large-diameter casings in which drill pipe is placed inside the casing as the conduit for pumping fluids from the surface to the casing annulus (Fig. 1). The inner strings can be run in one of three ways that will be discussed later in this article.

Fig. 1. Inner string cementing (drawing courtesy of Davis-Lynch, Inc.).
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