Traditional perforations and upcoming laser perforation technology in oil and gas wells

Once an oil or gas well is completed, casing and cement isolate the wellbore from the surrounding formation. Fluid communication establishment between the formation and the wellbore needs to perforate the well, either for injection or production. Perforating is the hole creation process in the casing that passes across the sheath of cement and extends some distance into the formation. The majority of perforation operations use the explosives (shaped charge). A perforator is generally lowered on a wireline through the casing to create an open path between the production string and the formation. As effective as those processes are in hole or tunnel creation, they alter the rock and cause damage to the formation around the created tunnel. The altered region permeability is substantially lower than the formation virgin’s permeability. The petroleum industry welcomes new technologies for perforation which is laser perforation. Laser interact with rock and transform electromagnetic energy into thermal energy. In this method, temperature is controlled in order to spall, melt and remove the rocks. The Laser generates a thermal process that improves the rock's flow properties, particularly in tight formations zones. These properties make it a unique alternative technology to conventional perforating techniques that use shaped charge. Over past two decades, Laser perforation was performed for many rocks types and checked the characterization of rock before and after perforation. It has been proven that perforation by laser can generate large diameter tunnels and improve flow properties, thus enhancing the communication and the interaction between wellbore and formation. This work provides an overview of the perforation process for traditional perforation and its methods, equipment, the performance of flow, and the damage caused by it. Also provide overview about the new perforation technology (high power laser) and their tools and how it can improve the perforation performance.