Test Results Field & Lab for a New Composite Perforating Method that Integrates Propellant and Shaped Charges

Abstract

Abstract A new perforating technique employing the integration of conventional shaped charges and solid propellant was described by Albert, et.al. (SPE 197185-MS). The innovative propellant deployment method allows the propellant deflagration to occur in the perforation tunnel rather than gun body and casing, thus delivering maximum energy to improve perforation tunnel performance. Shaped charges utilizing high energy explosives perforate casing and formation with high speed metallic jets that displace by sheer force. The explosive events are fast (20-30 microseconds) high impact events (as high as 1.5 million psi at the rock face) that can collapse large pores in the formation along the surface of the perforation tunnel. This crushing along the tunnel reduces permeability and increases skin and can impact the flow of fluids into and out of the reservoir rock. A number of methods have been developed to improve perforation tunnel flow efficiency, but all suffered limits on either deployment or effectiveness. Propellants have been used for decades to improve perforation performance. Propellants are energetic materials with slower burn rates that can micro-fracture the formation and break-up the crushed zone around perforation tunnels. Prior methods deflagrated the propellant materials within the gun bodies, or casing and lost a significant amount of energy before delivering impact to the perforation tunnel. The new method with a composite cap of solid propellant on the face of the shaped charge, displaces the propellant into the perforation tunnel before deflagration, thus delivering maximum energy to the formation. This helps break up the crushed zone and micro-fracture the formation. The improved perforation tunnel will reduce frac fluid tortuosity. Frac jobs can get better fracture initiation and better proppant placement, resulting in better production. This paper will focus on additional lab testing at an Advanced Perforating Flow Laboratory plus several USA onshore completions (horizontal and vertical). The field data will show the effect of the composite perforation method on frac performance and well production.