Well perforating—More than reservoir connection

Abstract

From upstream to downstream, all phases are equally important when developing an oil field. To extract the hydrocarbons from the reservoir in a controlled manner, a connection between the wellbore and the fluid contained in the formation is needed. The most common way to make this connection is by perforating tunnels along the cemented metal casing and the rock behind it. These channels will allow the formation fluid to flow to the wellbore and consequently to the surface. The characteristics of these tunnels are relevant for production and need to be carefully chosen. Not selecting the right perforating system and or technique will affect the variables that dictate the production rate. In this paper, well perforation techniques were reviewed. Perforating parameters, such as depth of penetration, tunnel clean-up, entrance hole, and pressure balance, among many others, can have a severe impact on the final production results. We will demonstrate that the challenges faced by the reservoir engineers, during the designing phase, in choosing among the existing options are just the beginning of the integrated and collaborative workflow. The balance between the “best” perforating technique and the expenses of using it, must be carefully analyzed. Usually, the value difference between the charges, guns, and service providers is the smallest portion of the entire budget. This factor makes the choice of the gun system a multi-disciplinary matter.